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Transcription
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NOTES ......ON ...... PHYSIOLC)GICAL CHIGM:IS~[1RY, BY . ALEX IUS McGLANNAN, ~ AI'lSOOTA'rE PROl'-EBSOR -, <-F . PHYSIOI,OGICAL lVL n. CHElV.IIS'I'RY, COI... LI<~GE 0)'<'---- PHYSICIANS AND SUHGE()NS, IHOO. in the plant r(~duetion processes and s:vntheses,conliving force into potential energy or chemical tension~ are the prevailin~ forces,we find in th0 animal body ~he rsversec I eav ag e arid ox t da t z ori pro~ess es ~wh i en c orivsr r chen;icg,lt ens ion into livlng foro6. While verting b; This difference must not be o~errated,nor must a sharp line considered to exist between plants and animals6 There are syn- . thetic processes occuring in tho bodies of animals;and cleavage procssse~ occur in some plants.ln animal organiem the proc0Sses of oxidation and cleavage are j:;dominant~whi.le in plants, those o r' reduction an d synthesis most often o ccur , CHRMICAL COMPOSITION OF ~'HE ANTMAL BODY. An elementary analysis of an 8nlmal body ,Shows the presan~e of the e!em0nts,C,H;O,N~P,Cl,Fl,Si,Ca,Mg,Ne,K,andFe~With the oCC~sioDal presence of Al,Mn,Cuvand some other elements Which Occur irregularly and cannot be looked upon as normal constituentse The elem?nts C,N;Oiand H,oacur in the largest proportion.Or the metals Ca,Na,~nd K,are fuostaBbundant. The various SUbstances reSUlting from the combination of the elements are classified into the organic and inorganic constituents. The organic class is sUbdivided into the nitrogenous and nonnitrogencil5 groups. NT'I'POGENOUS organic bOLtiC:S form the cn i e r part of the solid animal tissues and are fMEru~.xfound to a consIderable extent in the circulating fluids1the secretions and excre~ions. They belong for the most part to a group of SUbstances known as the proteids or are SUbstances closely related to the m8mbers of this group, and for this reason are classed together as the protein SUbstances The proteins are a most important ~roup of sqbstances oCcu~ing in all liVing tissue ~and will be considered in detail later. The nitrogenous waste products Urea,Uric Bcid,and the Xanthine Bases,Creatinin &~.Pigment8,ferments?and other bodies belonging to this class will be trijated of in connection with other SUbjects. NON-'NI'l'ROGENOUS Fats,and carbohydrates,will be considered in detail later on. Pormlc.aeetic?proprionio and butyric acids,are present in sweat and othe~t l uL:h:. Lac U. c a c 10. occur s in muscle. Phencl occurs in various CJcbinations in the ur~ne and intestinal canal.Benzoic <. aci.rl! the ttl ally C)iJgUtat:::, l1u!J}~~-: ']'.h& ~:r·.-i.~1·:3 i~l ~.ncrga.n.i!) constitL1cnts pact."directlY freel food ....., most s ys t en1 111-lal t ere' d ~;:;O.l.·IJe r,":.s: f? • - 80;1;e a r e -n6wlv;"ar",'p,;;' 'C'''' .a , n -' --. ..J ~- -j.~.,.~ '.• 1 J, t.: .~. 'Y ~~ \...... -",I ~. t ncr g an ; c; C 1 a::; s i:=: :.0 e;:: t;;\ i ~~~liri (~c:}~~titue~t~u ';'he G!lSE:S.~ gas60uil L,'-"'A,- ~J ~J \, J \ .• -~J..l.J mattt:::rs ...... ...,. .... or i I' -:..~ ~ the 1 (~e j [.June! .£.. J.~' ... (".... c~ ,...r ... ,""\"'. ": - .. v ..~ ··u ;¥".; "r':) e {.t. t:..; r throug"i 1.. l,. .... c (l~::1.l1 p art t"''-... ,'. ';"-::1. .':./-~ ..L ~ v ~3'!... ...... ( lor t he. 1;116 ... -'va:'.'l., &,t1<; c~~f -r-f'c. ." ... 1"" Water. '!: .h e i. n L) ~ .~ 1. q U 1 g 2.:3 e G'0;:; d; b:J<~Y 8:"13 oX'ygen~ the ill ~ ,.., 1-'" . ... J.<yHr\·)e.ren"la~lG hy(;r';';i:!Oi'~ :?,::" W(~J.I CJ,s r'n'" t;, f...,....·, d..i. .f pEUG .... ~.:\ n;+~~'ger' c~·~o·cu·~r"t·". ~""""L""'-' .... ""c'-'-, l ........ ~ .... J 1 t..<... ~L.Jt ... wL:.,,1.!:Jl1.'.:..iE; bon.iG a~~:i(L(rho fir::>t two in tilE; b}.co~"'j;~;,d ~li'fd:r''''1Q~ > /:;.x-r~ t....,~_d, .!oJ.L ...... of , J' he and t-,·liYl'"'I.-.., ,-=. __• $ ..Li. :J..rll":::;,-;._tJ-.;'tr!;(' c.. ...( an d dri..c;k;?.L::e;: o ~.~,·i·A sr r-::·r j (1 (~l·'.-lr) '.,'",I:: - .in t h e C)v";)v C2rbanate2~and some t and sUlphates 1\ ~ r-.«... 1J0:(L,ivorE1,,'::,;](i [",?r:;: I)j ~~.UY·~~:-: .... 81..i. (;&.1"'- 2n '-~ n i. U- Ci-! 8n s.n d C8.I b ~n',· 2'~ e,:l2,nd. :::.,;.'-i. pl', ;~r i'" t',,:: Co i~lY L~r"c't:~en are i:!th8 in:,-:;;:;tijJ3.1 t::~~~L'3.~,Ga,r~-.;-,:,i,., [:',jj.!~ ~>o, pi"ei~C:;;lt In the bleod f~:1d ot.!.c~r rJ.u,i(~_,': .. and .1.'-.,' e·.V.i·'!'c-1,·:,."...•."! -"'J ',''"',,''C ("l~"'-""~~ ',. the <-........ :i. l .. l~ J '. lUt!gs,.a[l:::~ in YGr-y rn:il1ut2 "L~ )'-~d! (::,y tilc' ;c;l':i'r:;, OX}gen fcrIll,OC{~ ~- • • -"'~ - ~.- - -'- .~ .~ •• t.;" ... ...: OJ' v thrLl L'No··th1rdE' cr C'l;:; w,-':i.ght or bodY"~~d irnpart~~~e ~f wstc!· as a 0008cituSDt J( the is sh~wn In a strickin~ mann~r by irS :2mo~2:.1~ sny h(~ate& F~,uft101.p~-"r_lY WA'l'~~E,rGrm~~mor(~ lJ'" -..... all ·~/~;-- - .... .... ,f .. ,.... ~.;",~, "-~L.J,,. ~ - ... - t~J":" .. 11\.-, ·; ...""Or-l·C).") \.....r.{,~ .._J. .. C.!. : charac.t::;risti:; .l..t ..... --- In j '~J 1 -- \.... l - )":jy"T 1 ( ..._ pt1y.::;ic:c"J, pr'..Ji.JGrtle:: Dre r~(,-fi~H:r,.eX50V§1{CJ52r~,"~p~$f~l\ and flexible,becomes J ~ ..:.. Cl ~ t·...... L r (; (~0 g :ni z a b l e .. - ~ i its l,. ,.;" \., ... ~ ~ ...-;. tht:' wl'!.C:','3 animal body tis~ue,be ,..--.,f-"$ ";·Cr-. '. ~ [ 'ti-, .... -Ya\", • ...:. +e .... .a.? :::'28tl'oved,:e.n,,! harJ"brittl(~ What and .)'~ all the fluids or the body -. bla,jc"lYIDPh etc'··\~'aterls the cool'lent,and by lts mc:a03 alone cir'cula.tion uf llutrif;nt matter is possible.It is the medium alsc in WhICh all aliments are dIssolved bofore absorption.as welles thu moans by whicn all? AX~(}pt ga~eous~Waste producTS are rerrloved~1'f1eprOCG~32es ot' :3ecre~ tion~transudationland nut:ltion depe~d on itG pr0sence for theIr Oi:rf'ormance, ~·:'lr·er8.1 'l'he gr\~ater part of t..'8 W:':llsr oresent i1: as such frOIlJ v::d; uutlc,s food and cn~ result of the chomi0Bl '."·ganisrn. E1 Into '1'he ::'o~:s of ,:~xGrGtion the fl.limentary SOLIDS, Sodium ()f the ~reat8r In water tJ18 f:r~)rD canal" I; t.hEtn 11"1 ohlcrides are 0reSB!]t ~n n~arly tJ 1 \) d \I the q l] ~~rl tit ~y () f ~;c d i 11m e h!. c~r the Ii').;.]."!". uf' -in the '::...,].~_ t!~l(:- 'jr..nor ~;.~.0C(! of cf that functions perts ·.~_S i.:~(~J81.1J..)r.ts~ rut2;:=,'Sltlm :s<':,J,t .L" i:::: !Jl'8sent~'-:bi)j>c;~~ rnaf-,Zcl33iurn "'...... nd flutGoln ,Ie i '-ii.i} e Z l so:.::rce of their the 211 .l .-1 e <T8,j"c.'2rc ind teeth; f';OL1S ~);":hr3~~-'f."11.liL~:3 ~ s.nd ;I principal sa . .l::"r~e 2,n;')~(:~t2 C31~1.urr..nota3s-;'um.,::odJ.l1.m.and t""" .' , nea:cly every tissue tee r. i'! ; P 110 S P .h a -c 8 0 r ·the !:')dy i:::; :J.Dtim::'T.~~l~. :.;c;rmGred ].'lith ktd~;e:y-~·.~ ~:.:i.1'.: t()-dJ<';~:;L:;: }.~,xtf)nt from and pot8ss~ur bod Y oC·~lJ.r furmance L'Je bO(lY is tal,erJ ...1. !1.L18,11amount is the r'U!;1 111l:1.~.·,~8k.irl~, the muse1.r3s 7lLe uaDti.t.y Cal{"::'um fluJ::-tde.! ~,n ;[;1;:),;·_3 traces ,jrink Dh:::.;scl'ICl'l.6':: _. ~lra found in tht Jones and S t-c: i n V' e r- y 1 ;J. [ e; c:. q iJ 8. n t :i. t Y, and 1s IJ6.!"dness ':)j} "r.h:;.ch t.he proper per.' EC,j"ie depends. casC:'Sj3.S .. \';1 ;. 'l\h~-" l):nOSp~~[:,~.e org ao an 1.1, g8:18ri~1 tho org an i c or :::dl8.pr:'l 3 .... "1 +c.~ . rOtassiurn and be ee~'j o s the alkalini1:y' c)f d soft i um emov d by e p h o i ds w.i t rio tne with ut destr'tT-y-ing i.t~ rri- f}.exible~ 7rrtn-; a t es a aft eF-..UH: rf}movAJ~ce-r- tOlJg119Hnd s p.ho ~nc6rporated intimately r the \Qon(~l whi,:h left ~.~~~ 118 is ~i=:~.clum ()f. ITiiHrli,but the c ar-bona t es i ma i n ta i.n bloodo th~ in bones an~ teeth,brit in mUch sn:~a.llt"r ouant rtv ;:!'12n ·::r.8. os p hates Lt iE found i.no tn er p ar t s , 'l'he S;-()EtlJ. c onc r e troris of the lSixinterIl81 eer(Otoliths-f CiT::,;) p ompo s eJ ot~ 01-ystslline ~a2ciJm0carbonate,and are the only inor~anic . cry [3 t ::1 },. ~? 2 X t ~':; t i r~g 8.. E.; S '1.1 G h l., nth e ~=)0 dy' o Po t as s i. ~lrn:- ;-~:'0 d t ur» an d, c 1:·:L_L c i 'urn s 1..11 [J ria t (~S a.r e f o un c in srna,ll 8.n:-01J11 t· In mOG~ o~· :i16 suli,Js aD~i flui.ds of the body·.PotasSit1ffi aci,i S Lll ph ate :i. s feu n dec· [j IS1, t; r:,:"j iT 1 t h ph c; no 1 s j, nth 9 e x c ret ion e • Sili·;:cn o c o ur s 0.11 n;_;,nu, cO ijU8Qt.lty i.n the lJrine~8.nd the blodd. rl"t],(·f::S oC it l·l£:t\·~e !·)Pf-)~~ f()t ..~:n ·;:i-l S()i -;.r: bones? hair and other pa,rts. Calcium oarbonate o~curs « 'J Ih'.()N~ ~\fl~t}::~fJ;;;t)eci[3~l c,r the maiter withtl~8 Per~-oxide tiOll troll ~:.lct::,~e :f bJ.()(')..i~')f an vrhlC1'l :i.8 in el~eount the colorillg be given in connec:- 11{ar:noglobtn~i will b~l0Cd~ :~~:r0:C1is qLlf.llltities in the ir! J..YTrpll and C,h,y-let c.l~)\.}:i-j~.~·n.~)()f' ~~eru;'!li' fj.bi"iIi 1.·.i.1G,;~1.~.i.,~~k· ~~n.d cfth.?:l"'~. rluid~; ;6..rld a salt of iroll prot!8,bly a ptloS;Il:-i2.te~ezJ.s-:~8 j.n tb~ --·htlir,bla(~k pigIIlent alld ~l.stles Df or ,.oc>nes)r:nl"ls.c.les found D.nd J.n V6r.y sITJal1 t'iss,lJ6sljand O'Lflb't"' j lead are prObably merely 13-ooiin minute quantities qith the fo I\}\1::-Dl:~itc1,L;a:)ga!]PSf':1?e':)PF'er~8nd dental food"end , deuosited beigB Blo~ent3?whi0h ;')ot exr,',rE)ted in some neccs:::::::xy' ps:::'t·" depositorl in ttlB In at feces are absorbs ..i a.nd tissue or organ~of whioh however they form no th ? ~:;Ctrr,e mar/it-er A.r'ofmi9~being absorbcd,may be the wit.h the t li~er' and 'j'td.<::; C1C1.:·:;E::l:ti(,~~tlon a. gro~.:p~~~rlgof of the bo dv" taken ':')1'lCS ~78,rtolJ.~~ ott)er parts~ ~~·rthe (:(Iust::'luonts H~at~~:.a,7c.s , or c()r.)stitutin,g - 1.1'1e t;ooy,is tl1e food 2.1so nt~J.fr8 re~tly frol~ ~'pg6table IDatt0!'~r'erld6rs it 0b?ious the.! tile saUlS elements take part i~ the formB~i0n of animal food,withoUt regard to tl,e DL1,tlJrc a{ t.he Lt"(~:t~nc:1." F,)CD~·~,,)re thc)''3e (~U():JCDi~ices?which when te.kcm into the tJUdYt have no ijljm~loU2 action C):l the org<:111is.m?wtnc:h 881""e as a sour-ce of 8nergYji:1l-1~: Gen replf:1,':":: those cOiJstituents of theE body that have b(;e"'l CG;J~:'::rj(3d tr: :{':1,t.·,:.~,olisrn~{)r C8.11 preveni.. 01- diminish the C 0~·rl·~'~~UJ£r'ttic i; () f S l"J. C" t1 ;'~c·~Il.\~,"t 1. ·t. U e '0 t s 'l',tlf:' nitrt;'t{'3C:UU:: [!Y\'J ~:'s:r'\il:'"p p~~~j_ms.r·t.ly to relJair the wasted t-.i~.~~::ue~~.,).:,!:")ii ::.~~s·t.hn ·::ur:.·'r.l:~_~"_l"CF..~fIi·1CJ1.J~,: ill t,ile :ask of ~~ust~?1.iriii)bf Co animt"l haeat,and voluntary and involuntary m<.Jt~on. Tb e inorganic food products a1'8 usually taken Lnt o the wlth urgBni~ material,or dissolved ln drinking water. prOxlmate princi;les are those foud products WhICh through the animal body apparentlY unaltered. Ml.lk c on t a i ns all the DG~e::;sary o r g an i c and inorganIc body ,!!n xe o 0BSS o ons t it « uents of human food. Cows milk has alaimed the aLtention of investigators to a greE'ter extent t hen any o t ne r animal sUbstance'l"he rr e qu e n t ')~purtunity for of making analyses,Bnd the plentJfUl su}ply of material~have contrihutad to make the results of the study Vdr} complete.A~cordinglY a study of t~B composition and cunstitllonts of milk wlll lead TO B ~nowledge of many of the important r~ets PhYSlolo~ical chemleal interBHt. Cows milk like all ot~ers is an emulSl0n,~onsisting of very finely dlV~d8d fat,suspanderl in a solution of proteids,mllk-su~ar, and s a Lt s Lt is an opaquej,vhite or yellowish White lHllJid,in thin 1 a J e r s b 1 u e is 1;1 wh i t e , has ai' fa in t ()d0 r 8 n d H In 11 d , s 1 i is [1 t 1 y s \-/~~ et t ast e vt'he sp.g.of milk is ";etvreen lO'~H,and lO:i5. 'r'ne color of mi l.k is due to t he suspended fat globules and to of v r the dissolved casein. Sxperiment I.Rxamine a drop of milk under the mlcroscope. Notlce the varIOUS sized globules ~resent.-Com~are the microscopIC appearance of whole rni Lk skim m il k and colostrum milk. The raa~tlon of ~erfectlY fresh milk l~ general~Y amphoteric,due to the presence if mono and di calcium phusuhate.When exposed to the air,milk gradually becomes more and more acid,because of the conversion of milk s,]~ar into laotic acid,ty micro-organIsms. ~xper.~!-rest the reaction of perfectly fresh mIlk WIth sensitive litmus papAr.-Also some milk that has ex~osed tothe alr for a day or t IVO. Exp.3.-Boil same fresh milk in a test tubeand note thatvfresh emphoteric milk will not coagulate ,but forms a s~um,whi~h reforms after removel. Allow 30me milk to stand a few days,then bOll,-a cuagulum IS formed. If milk is sterilized by heat,and contact with bacteria ~revented the formation of lactic acid does not take place. The addition or various antlseptics,salicylia ac~d,borax,eta.will prevent the 'formation of acid for some t rrne. F',Xp.l±-'l'O a r ew c v c v o t' milk add a m,ixture of equal parts of tincture of guiacum and ozonized oil of turpentine:-a blue color is formed.Repeat with boiled milk Plac~ 400 c.o.of milk in a lar~e beaker and dIlute with & liter of water;add ~radually,starring slo~ly,enou~h a~atic acid, to p r e c i.p i t a t e the oa s e i n an d Le av e the llCju:i(1 o e tve e n the fLs k es ~ha flakes of ~asein carry the fat down with thAm. {an excess of a c i d is to be av o i rte da lAl Low tr.e c o ag u Lum to fall to the bar torn of tho v e.s s e Lr p o ur off the s up e rna t en t !,iquld.t'11ter first throlJii,h rnu muslin finally thr0ugh a t'old~d (lIter pe~er. IPlltrate A.) Pour «n the ooag cLum rn the bt3aker,f)OO (~.t;.0t' Ni-lter,stJr ~antlY an o a110"'1 to s e t t Le sRernov e the s up e r nat an t 1 )·41.:1(1 as c ornp Le t e Ly as p os s t o j e by de"8nl8tion.!o remo'/e mos t «r the ,,'<31.";r r om tn e eoae~ulurn,press b~tween f"{)lds of (try Li.n on , t h e n tJlc(}s (he (}(I.Oit!,Jlllrn in a dry murtar and ~rlnd tt WIth fOOe~c.absolute alcohol.~llow to s t nn d half an hOdr In »on t ao t w r.t n ~he 3,1IJvhol,then flilf)!" thro~dh 8 dry filtr ~aper and collect the fIltrate in an Rvaporat i ng dish.'1'o separate t r.e c a s e r n anu the fat ;!ress t r e (H,'R,.~ulum between folds of Ilnen and ~ork It In a dry ~00~.a.rla3k ~l!h [00 c s c •. jl:her.;~llov( \0 s t an d 24h()~lrs ;ll~'ltatl.ng oCl,.}l1s1onally;fJlt·:q' t hr c ug n a dry r i Lt o r p8.iJer,anrl i'/8,sh w.i t h e rne r s Un it o t h a f:i:noru3.1 and a l c ob o Li c rt Lt r a.teaj e.l.Low the ot h e r to evaporate SpUnlan'c.'t}'lS1¥' and remove t ne last t r ac es of a Lc oh oI an d e t r.e r by eV8fJuratiD;j over a "later t:ath. f~utter faT.. )tJla,~e t h e aas em in :;; rno'r t e.r a.n d rut with a ~Astle untIl the ether ~1/Bporates and B dry powder 1S j obtElne,1. Plao~ th r r e e rlftm~ e e l e ar t.o rlair filtrate its A, in \I'oluM~.'I'r,n a SaU(lAp~"!n '"r>ms.lnu1g ~rH.i boi prc,r'O;ids I ,WW2 0Y',~r a <cv·,:,~C;6~;U- 1a. u!d. • (;olle,:1 on a filter.lvash ','(j,lt' '.... a.tt~r flnd dr', With al(~ot",(jl 8ntl ,O"Tt' er,as dlrelHed for ~asaln.·fhe fllt.rate lSDJl~ filrlher evaporay~~d until"the deposition of cf\l~ium !Jhas:Jhau~ r,~2i;ses t1um}-iinH,(,r ;1Dll1 the volume is reduoe{1 to 75".c.,Allow to ~ool,filrr?,r and'VAsh t.h"" calcium ~hosphate WIth w8ter,~va~orBt9 the filtrat.e over the w~ter bath,to rh~ consisten,}y eT e d 2!fJ os t ted. of syrnp.On coo IJ. 11;,i; (~rystals ur milksugar GO MlIJ1ft:f D".1,8 Li<V,fT\J. a. XBntho~rotele Reaction.-Heat a small quantIty uf ~lDumin with concentrated nltrlc a<:id,-Che alb'JlnHl ur the sulution turns yellow.Allow t~ aool and add an excess of ammonla,the color uhang~l tv oran!~e. b.~111ons reaotion.~our afe~ c.~.or w~t~r on a small Qllsntiry 0f albumin.Add t c.~. Millona reagenr and haat to boiling-the albumin turns red. l(,Tl10n5 rea~ent is made by dlssol'leing H10grams of mercury in the same we1l!iht of lhp.nitrc '.\.}lO,nnd adding to tt'le iJOQl s(Jlulion two volump,s of watnr. '8<.11 a small quantity or 81bumln in ~ v:tttnlb,-" '..tth ~bsolutd aloohul.fI'ilter,~'!~:;h vtith al~ohul '.hen \\ilT.h ,Ht'h:r,t',ndus~1 t"e meldl isl j'0r th~ following tests_ a small -quant'lty of albmn'il1 by "ttotrtng witn 1fi-a-c.i..al .. aoetia.- Allow to aool and holding the test tube in an inolined position allow ~ c.c. of concentrated sulphuric acid to flow down its side. A violet or purple color deveLop es Where the two liquids meet. ( Adamkiewiazs reaction.) d.- To some dry albumin add concentrated h)drochlorlc a~ld.-~he albumin turns deep blue,-on standing the color fades. ( Llebarmans .e,..... Df ss o Lv e reaction ... ) e.-Detecti.on of n i r r og en in albumin."", P1,,\)(: a small Quantity if dry~. albumin in R test tUba with 8 or 10 times Its weight of sOda-lirnc,snd h8at the mixture over a fres flame. Ammon ia is iSiven off and GAD be identlfied o v its odor/Uts ac t Lon on litmus paper ~n copper sulphate paper,and the fumes whioh it forms with hydrochloric aaid. F.-'J'lv, La.se ai gn e t es t s v-P'La ce 8 small quantity of albumin in a dry test tUb8~ad~ a bright Uhip of SodluID,and heat carefully over a free flame, Imser26 the end of the tUbe WhIle it is still hot in a teaker contaIning TO c.c. water. FIlter and to the filtrate aad a rew drr-'I<:',)f f6rr.ic c hLo r i de and fsrrous s uj pna t e s Hea t nearly to boil~n~ 2nd eftGr coolj.ng aCIdify wlth hydrochloric aOld.-A precipitate of Pruss ian Blue is formed. g.-' DC::>:)0:::;.on of G'J,lpl'iur in albu!1nn.-Mix a small quan t i t y o t albumin wlth several p~rts of oxidation mIxture (~otasslum nitrate and sodium carbonate) and heat In a dry test tUbeuntil all organic matter is burned away.Whlle stlll hot immerso the tUbe in 10 XI c.o. of water contained in a small beaker. ACIdify with hydrochloric acid1filter and to the cle8r filtrate add a few, drops of barium chloride,-a precipitate is formed at on~e,or will a~~~ar on .... ' standlng~ I n.-.Detestion of reduced s ujpnur s » '1'0 a r ew ide add a drop or two of lead aaetate.Place al bumrn in the sol ut ion and boil. "he mixture the formation of lead sulphide. 2. ,,,.~.of s o dium h)drox a small quantity turns de,rtl b ecaus e of . 'f ~ GASRTN. ) '1'0further free the casein from fat ,mix half of i twi th 125 c. ~ of water and place 1n a mortar. Add drop by drop (stirring withKK ~ a pestle) a one per cent.solution if caustic soda untilthe great~ er part of the casein is d is soLv e dst'he alkali rr;ustbe added sloWl~ and the solution must not remain alkaline after thoroughly stirring.Pres the soll~tion from fat andsus~ended matter by filtration repeating the filtr8tion until an ap~roximately clear filtrate is obtained. Acidify very faintly wlth aaetic acid and wash the ~r8-· cipitate withwater by decantation.Flnally filter and wash.After drying the cBsein with alcohol and ether,repeat the react loriS given tInder coagulated albumin.Reserve eD*gh ansein for the fol-, lowing testsv • a. IW.itate w i th '1'1,.1[81" that has been rnade alkaline with sor rum carbonato.-The casein dlssolves.-Aoidify the solution with acetic acto" bo ed Gri~~ . ~ 3rnall DITOunt of easeln in a mortar with freshly prepar calCIUm Hepeae s and aCIdIfy the filtrato W:i.th J. 1:"'1" \"21 pr, inlJlscc: Cif carbonate.Fllyer the exp(-)rlrnent c • - Mix idation a qua TJ t 1. ty (j r ens e 1 n lV:1 t h S i:1V':; r " 1 ,J E' r t s 0 r o x _ fUse as dir,c;,:t8d Linder d,-~J:i:1:~:i(Jn of ::;Ulp,Fd' In S rna 11 mixture WIth acetic a~id c aI .. >i:-,ri: ,;ar.b. and albumin, IlSlng ni tr", lnstep.d of hydr0,;hlori" aCl", tor- ""'''ttY,n" the solution. Poor a small qUADTIty mt' thIs SLIUtlon Into an 0X0ess of ammonIum mc!ly"bdate and ('/':,Ttj·).A ',';"'lln\,,. ~;J'-. ".·",·~l'.j,;,.L·,.·_.~.,"'., .... "." .. ,'"f h'S" '-"''Y'' lYbdate of ernr,10nium 3 BUT','!':P ?t.,'l'. Pla{:o ::-J C.c.of o r' i,~r'8ms in:5 is form~~d. vessel ~r", J.n .. _ " roOe• 8. "._ G. , ,<l.·L' - '"' Ler ~_).!.'.'.) _... flCi:3K 1:1";;1 i ntc t .... f.' nl"·'>.l·t"-~,.·l·t'·I·~·l"-··"'\' ii, the .~ pc;tssn l:aUSCJe; Wat8r,i'our .. .... t' il.vL ..Jl .... ;- ,11Sso1ve "'1' .ne lU i..i . r~;:iSi{, b~;h ~i:jd :~ont8.lnedtho 1'1')1 1>/1 th tD(~. ;~.,(::f e.l';ohUl ,,:r'<1 the WaShings to the ~ontdmt3 or the flask.H at tha mixture on 3 water bAth un t ij a drop of 1{ is found t o be~ '~omplet:;} .sultit>ll rrr "~I a t (0) r , i n d .i ,;a tit) g e ()mpIe t e sap en 1 fie 8. t ion. - 1;'] h ,Jr) t 1"1,:, 5':J,::;()': 1 f J ;; d t 1() n is complete pour the materIal ~nt() an evaoOratln0 Ul~h An,: ~V0~0ratE' the aleohol over the Water baCh.When ~hO OdO'~:ot'nJ';vt',:.JI 1~ no n lorger l"ppar';1 t,add :jO r:.G.uf' diLt2t~.3 SUliJh;:;rJ..e Ct\;i'l.f;y tl'J.s crc!:tt} mept the ss! ts or the fatty p..::ids 21'H dn,,~ 08(>.; ':'\I'd :JLli;.T,.J'::q.,: 1(1, can bn re60~niz0d by its 01or. ''i!'1tch 4.-CAlfGltYM PffC)SPtfA1'R. DiSsolve aci d. e.!-fI'O nilri~ t'he ex;~,,;::;s of acid solution an Make a 8bout and wc;rrn~-2 eold yello,\-' ..lU('.: i30C;"~.dj a sinall '::JI('I;; [..J01:T.iuTi of 'if lJr')G.l,)itD'C:; of Ine t,ile a:.~etl';: aW!liOOX8,1- 5 MII,KSU()AH. Decant the motber llquor S5 far as pussiblo B~d dry the crystals of mIlk sugar nlth;c~r on rtlter pat~H:;r or on lJ()('OllS pLji.'-;s.!-"or i.J;:rlfic~tion,dlSSolve the sugar In about TOO C.C. uf Water and B.ld a 11 U. 'l!'> .• ,,'•. ' :" ~ .. 'tt1f- .1 \" ~ha""'()"'l t·I'.~~ h.a.at t'u" b"I'll'nJ and t-·'·ll~lr "-""'11(~ _hJ-Gt.~;V-[),;..J-urr::.t.:) on the watflr bAth to ;>,;"j .::.c.G.nd 8.1101'1 to :::;(;:;.nd J.n a ,~oul til;:;c:e for 84 .'<J ,', hours.Colleot a.,-A small quantit,Yheat""d fIltratIon and dry 00 filtAr paper. on a. {JlatlnurJj fpil Turns b,l"OVofn,til" ....elp as a caramel odor,carbonizes Bn1 the aSh. 14'01' the (T) fOllOWing 2 grams ("2) T08.C. erYstals by reA,~ion5,rnaI(,J of mIlk sugar,dissolve(j of (T) diluted WIth fInally two 90 burns,leBvlng verj little ,sol!.it.i.ons. in TOO G.C. Water. \1!.'nr-3r. C.c. b.PF.HLT~Tns 'fRS'i'. 'j'O;;' C.(~. illixedf"ehlings SOll)tior: add:~ G.C. of mater and boil. Alta 8 few drops of SOlUtIon (T) and ,~ont.lf:ue t() boil .The ;,rello\'1 prolnpitate (Gl;OH1/'trst rormi'~(l eiE,O:,::<;;s un boili. i5 n to red ~uprous oxide. c. of first a~ marked MOOFiF.S'l'ES'J'.fJ~r cent.·:austic yellow, after ''-'0 :"i e.c. potash of solut.ion solution and (1) 2.<1<1,b.n boj_l.'\!it~ il SJ:>uOnJlhu n.1tri.,:: 9.;,~i(1 SUlUtIun 1:11kalln-:;; 'lJ.th a,~I(j,,1nd add 8 tow' drUtlS uf alFU.c;onll:m of calcIum oxalate. port<i;.iDn nlfi,a.::idify t','j_th ate.Apreci~ltata If) '3,mmonlum molYbdata phosphomolYbJate. b.-. P,hlsphr,ru Gal,~i.uF; oqual 'Jo!u me ~Oll1tluD lurns then brown,and de"'(~lopes a carar.rF~l (ldor:;h:i,'.:h the addition of SUlphuric acid. 1S ITerii' d~ pismuth test. Make 5 c.c.ur solution (I) strongly alkallne wil'h sodium carbonate. Aad a small quantity of bismuth sUbnitrate and boil.-A gray or~ black precipitate is formed. e.- ~o 5 G.C.solution (1) add a few drops of sodium carbonate ad Rnd a little freshly prepared solution of potassIum ferricyanide.On heating a colorless solution results,due to the conversIon of p potassium ferrieyanide into potassium ferrocyanide. b.- '1'0 5 C.C.of silver nitrate add enough dilute ammonia to dis solve the precipitate fIrst formed,and in addItion one drup of caustic soda.To this solution add a faw drops of solution (1) and heat.- Amirror of metallic SlIver will be depOSIted. g.- Indigo test -To a portion of SolUtlon (2) add enough Indigo carmine to produce a blue color,and make alkaline with sodium carb onate9- On heating the blue solution turns successively red,yellow and under favorable conditions becomes aolorlesseCool a portion of the DolorlBss solution and pour it several tilles from one test XMR ·ube into another;-the colors are reproduced in reverse order • ._~iha following tests will dIstinguIsh milk sugar frum grape sugs. ·...Lch responds to all the foregoing tests. Shake 30 C.C.of solution (1) with a small piece uf yeast,flll into a sma~l fermentation tUbe,and alloW ~o stand 1n a warm plaae for 24 hoyrs.Make a similar test with a 2 per cent.solutlon of grape sugar.The gas whieh collects in the upper part of rhe tUbe is carbon dioxode,and is a measure of the extent of fermentation. Milk sugar does not ferment with yeast. i.- Put 5 grams of milk sugar in a 100 G.G.flask with 15 C.G.din lute nitric acid and 5 C.C.concentrated nitric acid.Heat with a free flame,under the hood,until a violent reaotion takes place.Remove the flame and alloW to stand 24 hours. Pour off the nitrIC acid from the crystals of mucic ao rd wh i cn have been depos i t ed , Wash with water by deeantation,filter and dry on filter paper.Dissolve a small qlilantityof mucic acid in an exsess of ammonia and evaporate to dryness on a water bath. (Hood.) Heat a portion of the reSidue in a dry test tUbe-pyrrol IS formed by the decomposition ~ of the ammonium mu ca t e and can be de t ee t ed by t1;)e red color wn t cn it imparts to a pine stick mOistened with concentrated hydrochloric acid and hel(1 In the mouth of the t ub e s Re pea t t r.e exp er arnent xi: with grape sugar • J. Weigh accurately 3 grams of pure mIlk sugar,dissolve In water and make up the solution to too C.G.in a measuring flask. After thoroughly miXing fill a 2 deCImeter polarimeter tUbe WIth the solution taking a~re that no air bUbbles are introduced. Find the zero of the instrument,insert the tUbe and turn the analyzer to the right until the position of extinction is reB~her.Read the .B8B~angle and calCUlate th? §y~cific rotati()n from the formUla -r-: .A D. =-A..Y I. W A D.represents the angle of specIfic rotation, V is the volume of the solution under exarnin Tlon, ;1'1 r ep r es erits the '!f:df£ht of material in V, L represents the length of the p o La r rme t e r t uo e , a represents the obSBrved angle. Calculate the weIght of mBter~al In the solution ooothe assumption that the s p ee Lf ac rotation 01' rm Lk sugar IS .);6.:):\ P PIece exaotly 50 C.C.of the mIlk sU~8r solutIon In a Plorenue flask with abollt to C.C.d11ute hydrochlor1c aoid.Boll ~entlY r or ~() mi.nu t es n ear-Ly n eu t r aLa ze the a ci d w i t r, !J(Jifdsred s o da urn .car bonet8,trBnsfer to a 100 C.G.measuring flask and after coolln~ fl1 to the mark with water.PolarJ.ze the solutIon In a ~ dm.tub~,multiply the observed an~le by two and aompare w~th the rotationObserved before hydrolYsis. j ~,O'rIO"J ON MU,K. Of" kf':NNIN Prepar e a solution of rennin b y a i a so Lvorig .lgram' of t h e commercial ~reparatlon in 100 G.G.of water, and filter th~ solutIon. a. Pre~aration of paracasein. Plae8 100 C.G.of milk In a beakor, add f~~~XMX TO C.G.of the rennin sOlution.Mix thoroughly and alloW to stand at 40 C.for a short tlme.A coagulum cunsisting of fat and casein soon f'o rrns an d an a qu eous fluid (the whe,v,,'ihi'~h con t a rn s prot ei d ,milk sugar and sal ts;) .1Sf.Jr~3SS ed out •'rh~s a c t i ori 13 s ugg es t rv e of lhe clotting' of the blood.'j'he ce.se i n ob t a i.ne d b" c~oagulationwith rennin is oalled pare-~asein and differs from the matet ial prAClpitat~d from mIlk by aeetie aaid, ~llow the coagulated milk to stand 24 huurssnJ de~ant theXKke Whey as cornp Let e Ly as possiblf:.Stlr t h e co,<iI3ulum wr t n wat or In a I!l mortar,filter and wash. Press the p a r a ca s e an dryvith linen, and treat a small portion of the material with absolute aldohol and ether as under casein Use thIs portion to make tests a and b ,~lva en for cas e i n , b. Heat a por tron of the wh ey to bOlling,-n voluminous eo ag ul.um IS formed. a. WIth a portion of the ~hey make the guiacum-turpentine test. d: Warm 2S C.G.of milk to 40 C.add 2 C.G.of a Tper cent solution of arnmon i um oxalate and th en 5G.G.rennin s o Lu t Lonv S'tLr and allow te stand.-No alot IS formed.When convln~ed that ;oB~uIBtionvill nc t occur 'Under these c i r cums t an c es ci v i o e the WIXLm e into t wo purtlons.To the first add an excess of calcium chlorlde.Boil the s e eon d p or r i o n and add oal c i um ch Lo r t d e .- The iJresenae of c a l c a um salts is essential for the pre~lpltat'on of paracasein,but not for the action of renn~n.Cumpare this reaetion With the clotting of blood. ~ Influence of acids and alkalies on rennin coagUlation. Tnto each or three t es t t ub es A_R,andG,placo TO G.G.cnllk.'l'o A add JOdrops 0 f • r.per oen t , ny dr o ch Lo r Lc a c i d and to Ba fEF'1 dr op s of sodium carbonate.Place lOC.a.rennin solut10n in each tUbe,warrn to 40 C.a,nd note the order i n w'hieh eo ag uLa t Lo n takes plal}e. j j II 4 D~' ... ~ 1: ~~T J~~ (; J. •• \.r .1. '. ..... fI," 1~ "J"" '. T (~ "'; (j'~' _.,.,'~ !~" .....-•• 1,\'1 I' C ,~ (',~R,"r ~\T Ci r.L ,ri"', 1\1 ~l t ~ ~!t.),.;4~·~i1 }... "t" ' , ~ .... .r ~ S 2, t u r 8 t ;.; ~() () r: r, c f !e:li Irt (I () LT I" ~. ,...~c- \, j" 'r.. a\, ..r- :i .\).. 1"'1 .~;;••";:'-~' '-'-'..,. '" t Cl <"J~ ~""'f ·'\.J·'f.J ;;::"I.,l ....... - • - ,,:,,:tti'l 0 U 1.- •., ~ -',. ~ , 1'':11 D.'\r'r' ',.'\\!1' l'~F:. l"" ,..,." l ~V '. 1"'.'1\1'.. "1 f i ':'":;. y !) n·.'1\i,y~~(~(9 J' ".J..1 t ....• ':·1" .' ;I, • r: '1 '1' "j ,t' l•• ,!..} I"l'" ,,,.'J,lf... l' .",.': ";' lfCLu.J r r·~l.:; "I:; (T:-......1t'~;,f.{••.l~'/J~ ",J', "..,. ... '" _ '"' ~( :,n:1 ph J'tJ<: ~~. F; (;~llI(\'j) •t 'f":.1", ..\.J '1 ,..,Po ,,", ••" 'c' 1.' , .. c'' 'L" .~. ",-i fJ." t~ <' ('i "- a: ('\-:. ~..., t-'- .._j.. i. UTI] S 111 C'h~.t0; 'i'h') f; t l'l 'I L F;~t (j.( (: ,': (',n'::1 L! L [J c\ f (:2c;;,:; c:;:L .:"g' r:m I.:~?' < 18.0~· eli; J. ob t,J. i:Li.' B 0 i:1 the r j. J. t rat ~" ,~I.e,:j:l ;!>,:~bi.:!m :i.$ r:'OJ,g1.1'.l., a t 0i~. F J.::w (' t h J n;c.<~~lT p)' e '2' ::'1":i 'I: E:'-',::;:; :~ {l (;;, J'J':~::'::' t a!' f..n d !~{!' .i11:i :Vt; '\'{,i!: n ;.;;0) io;::, fat t 0 ;!lS,s!l (:iE 0 O.Oow'~:it0'J:'.A.tt~o'~~ s:'8.r:,d:i:-:,g hours 2;1, tion uf egsai~6~8n.~ont~inin~ ~_- &s ... ..; M idfq.,'rd j,t ac_,.{~ -. ~ (1t -, . ,,<.',13 .1 of" e ;<.\1 ~,. _.~ ...., -', P. 'y"'~i,15. ,t-'·.;Cc,. ;......; 't '" t ,.... I Pr;j,ng.,·!-nJ<)'Cl'"or pr Qijce-dLrig the m~t0ri~1 o,porti.on j,l~ inil]~~'t'u ti:.tratc if, 2. sol~'~ in the aame condition fil;;~H'li· ..Tho this ~ the f;iC1l-utic.n [-~d(( e.0e~ic ,(,'10 j~r~I~J~,(~t)0:" p(>l·~j.O:l rd::'k 1;)xp0ri;:,::~rl'r. l~~Pi~,G:t.~ on clIO co 1AC'l'TO /C ';'0 ~ ". ,... grt:t;';:1,;:. Ok ";'",..". AC1D g:::'E,,;~l~';of \:I~n::' fI' . ';..;:-; (",.3..r).,),).(l}~'"'J~.''J\''' " ..-....... ,~l,""t:. :'I ~ r,'g.r~M2~N·;·J\'tION,y slliJ,tl'" j".'~ .'"' '"'" 1,)" (';;;'!:H~ol".od in !jO(; G,Cill,if' .,I/fi'tl;)l',r;l..J,110 CI.\.J.. .. S"''i,·1"'~ w",.,.~.,<:,IJ.t~i '\r t...... r1 I:' C!J ":1 ~'"L ", t .,.j..,1, Y 'vYLl,.:. . .J. /1~ UL"'.L, 'J {.. "Y} ~ ... o-j -/ oI~ <OJ or old ohG~~0.Allcw th~ miXlurs to stand in s thormostat at kG O~ for 8 01' 7CHr~J:;~I})\t. ti:H', :~:G:l of' t.hifol tl1i;';;: JH'm.t t.o bf.)j.:,1.ng ;<mrl filter VlhiJ.f) 1.h'c, ~d(';L:ir." J.::;. !l..J·~" :;~tH~ fj'hp. fi,1r:r;,1te ot'J ,'00.1.:\:(1/'-1' 'will cl61H:e:.it QrYsta,ls ~f ~irlc la0tat&o H(;(;l',i",-::L311izB cho c,alt under the the c~Y8tel~ the mut/lor liquor . of frmr~ end dry ~AtW6en or [fi~;'I)'I'/6 by [Il:;,lr fJUs.:d.nlJ tho ha.g b~;en p:rEHdpitatede!"iIt0);, until aU. hY"d:t·ogt.Hl 1tulp.tlida in e sepuratin~ funnel add and filter tho app8~'('Fml;!& the ,rY8tQ~S from iliJtic~ paper.When , mo16.-:mlEHI ~at·c()""lfl';'1ti{.i tlWGal or llcld,contains ,zinc.: la~tate HS ge.s into Wl:lt":H" microsaopeeSepal'aT6 in the air Ule sb.l't contai.tls :hzp..tian~WhiJ.f') the 7.ine 3aIt i~' WHH ,1ul'msntaUon laetic ~)·YJJtaLJ.:lzation" Sf~}t hl,)t allowed to dry 01' crYfHal'" we.'t(:;j):' (If: a~id Whio!'1 two mOlecules .1.11\'fE1,ri!l W~tcr' ii'J j.som(;.r- or water L'\nd '~Z:I'J(:irilpczo tiie thewarw sol"lt :i,r)t.l un t i}, t),11. triP; Z10" und nea;t the: l':tltl'Sti:J 1;'0 ~t wa~t)'r' bath hft~J tl0en tnt, IH>lt:.tj,on aoid and extract 0xf,JolJ.C;,L .Pl 11IH3 B drop of sulphuric 1f01ume of ctilOr.F'i.ltt}):'" ":4r;~ t~\,)n;lOn of' ettlEtl'i.t ·,(,rough a dry filtel· parH:r irlt',j a dry t'la5;k.~va'porate the ether O'lor a Wt1,t~r bEHh Whi~h has been pl"'I~'l/iou31y fl0attH! to boiling.AVOID TH~ NEI0HBORHOOD O~ FLAMES AnD USE A.CONDENSINn ARtWi~6 '.'l.it.lI e,1 solutioIl t"P~ /'7I:.,FOta.:i.. RANGEMENT. ~ermen!8tion lRot1e 80i4 obtaibed in this way ia 8 '01orlessliqvid solUble in all proportion! in water,otnar and alGoho1~ Urr81manns test (or laati~ acid.To an aqueou$ Dolution or lactit actd add e. fAW dNipe of e~J(ld~ UCf;:trmannfll reagent i 10 G, c~or a 2 perce~t gol~~ion or e~rboltc a~id in watar,CO ~11~h a f~w drops or forrid dhlorid6 ha9~b0en added)-AlmOb yell~w oolDr. OtJMn 1.'I'A'J'TVF: M'?Al/1S Tn Of,' MILK" Determinetion of speeirid S~6v1ty. Obtairi 8 sUfti~1ent Ao quant1~ ty ci' milk for all the ~lH:tl,yti~ work wlli6~) rol1ov"';:I~F'in& UJfi/ SP.gd, by meaDe ot a la~tomBter abd use this number for oaleulating the we~ght of ltd-lIt r't'o~n the ~iwwn Yolut(j~ 'ilhi~~h :1..z UtH'7& it.., t.b~ f01,10,,- in~ a~rA~minBrioDa. netermination of~ totalproteid by Kjeldahls melhod of determining nitrogen- This method IS based on tho f~ct that nltrogenou~ sUbstances on prolOnged heating with sulphuric acid are aompletely oxidized, the nitrogen being converted into ammont um s u l pha t e r'h i,s oxidatiun is spoken of as the di~estion.1he ammonium sulphate is R. v then decomposed bjo" distillation with an alkali,and the ammonia distilling over 1$ oolleated in a known quantity of a standerd acid solutIon.By titration with a standard alkall,tha amount of ae i<1 left un ejiang e d is determined, the difference between t h as number Bnd the amount of SCld taken represents the number of C.C.neutralby armncn iaj rmaj t rp l v rng t n i s by the proper co e rri c t en t the cuan t a t y of nitro.gen is obt'~ined.MultiplY the ·,it.Hght of n i t r og en b.y t·,. :37 and the ,prodtlct wil1be t n e ''1eight of p r o t e i d p r e s en t . Ized requited.-2 gJeldBhl dlstil1in~ dahl digestion fl.asks,H K.]eldahl :hstilling for buret ttol. ApparatUs Pea-gents requir~d. Pure hre'l:"eurl~ burettes,~ kJel tUbe,i'l,con deris e r s t arid flasks,2 j o.xlde,pure oon c en t ra t e d sJlphur- granulat&d zlnc,B solution uf litmus,a 33 pereent solutIon or l"otaMllum hydr'oxide,B. s·tshdard s o Lu t a on of so d i um hydroxide,a standard solution or sulpbU~i~ Qoid,~ ~olution of phenol-~hthalein in al~ohol. ~ha digestion. {HOOd.) Pl&ce 5 C.O.~ilk in a dry KJolJahl dlges t t on flaS'k;Add 20 n.C.ofconcentrated sUlphuri~ 811<1 and about an gram of mercuricoxide.?lace the flask in an in~lined posItion and heat g en tLy with a free flarne until frothing ee aa es s Ln case frothing is eX'ct3ssive a sm$;11'p'leiJe or parrafine may be added.Hradtta.lly raise th(~ temp@ral'Gre tint';l t'hesulfJhuril~ a·;~ld boils briskly.No fur ttl er a t tent lot'! is :rer~uired unt i 1 t he fig, t er ial na s cec ome co Lor'>l(!ss;ari"~sult whien is usita.[ly ob t at n e d in ~'>'O 01" ~~'Ormnu t.e s s Af t e r coolihg earefully dilute witn about T000.C.of water,keepln~ the rm xtur e oooi bY ag at a t i cn under a J(~t af(~old wa ter , The Distilla~.l0n_ Art·anga. the distilling a.~i)aratus.ln the r s c e r v e r flladeexa~'ctl:V 50C.G.Qf:"deci-normal Slllph!jri;~ 8;}id or a t s ec:uiv a Lent tit stRndard' auj;d' -brany stren!5th.ifl"ansfer the mat er ra.I from the digestiorifl'flsk1'Co the distilling rlask,llsirlg t3.bOiH 100 C.C.of d'1stilled W:atfJf" for i"1i'lSlng.Adda fev{ drol!S of t->henol-phtha. lein an(1 neutralizewlth Strong KOtI. 3t'it1~ a srtall iJl&t;e of ZInc into tne flaslt,:rrfake alkaline with :I<OH, and immedIately attach the flaS'k to 'the <hstilling apparatus.Distill off about 1.60 C.G.of the liquid And titr.te the excess of amId in the re~eiver WIth sod~um hjdhoxide.From the result of the titratIon oaloulate the weIght of nltrogen,and mUltIplY by t>.37 for the Wei~ht of the total proteids Supposing 26.:3 G.e.of <1d(~l-normt-n alkell were neC:'3ssary to neutralize the exoess of a'::ld In the reoeiver, then 50minu3 ~~;).j or;J.47 lCBCld ~.O.of acid w(~t'e n8utralized by ammonia.As on6 G.G.or (1eCl-nol·mal ac:id Bullaion 1S equlvalent tu .OOI7f:Jrams of nrnmonla or .0014 of nltrogen,the total nitrogen present is ~4_'7 x .OOL: (jl' .O~->,:±ot\gram .O~.,4!)B x o.:~7 is .224:3 grams of protAid in r. ~:.C.()r' milk,hbout 4.b percent. 5,~::,~ {;:klJ' ~v ~~ d,~·ld ]~L! .~~- .~. I{() !) C;r,~C,) ,:.:.'~f p r: ,) t (-; :~~~~ U .: ~,";],.. /::~d :',~i.t,":,,·~;,,~,~ :J<I.J (>~."j ':.. ,~'::,7}:~h.C) :~'o:;<" -~cfV~"it:.h j,"11IJilel s L~,dd·. 3\:';'PjJ.'!,··~)L j.'ng E'i: ;r:f~'(l~'je'~j ~ a f,~·'f:·'.)': :~'l.p~~~Ft; ,;{ J"~~i(JJ:{[;\l,d t 'i c~ ;~,:~ t~ t~j, ~~) ::0 'j C,:~·:~t};:ic~,i·l~~ ~C·:::~,£1[X·~:··~~"~: :id :r ~ r:.~():~,.i;t,:t'!)r~ ()1' :;li~ p i c r i ; r~I::~~,~:'l E~.~~~,~J fJ~(D.l(1 or ,:;!,) I":'~i"/'~J,~~t:;::l~ ,~",:':j. (:~ r (';;3,g :f) ~'::;::-~.;.;' ~t''~~~1u ~,'~)e (3) c' C, f~ me .~~:~1J.r~i It s f :i... :,i.:.):~ ) :l'J 5~) C ,".C D j"! G ~)'~1~~ 'f; t t {;::hri r" E'.~.t c:: ~JtE:"r d ; .~\)/~; :~j~}~ e: t t .~\'?:. I [) (~t' C :,,'~ [it eJ.ll f' ~'lgiJ ~.:cpr st' f;i () 7... ~Jt Lon ;\"1 [.! ~ '~~(J:hlj.T~'gr:3t,~:-~'ttrG~t~3 ~3GI':;Lttor;,.:a dj.l~'!1~'.',t'~, [;~:)I.ut:~()ri 'Ji' ·~s.'~·.!(:i~~~,},~z~ C.l' P;';-::8,r::~Bil1 / 'J ;:~ c rl :.~" j. 't .:;."f" r) ~.~.'~n1U IS Li.,~n :":i: ;) l'~.-~~)). :t d (:;':;1 ;-,~:):~"1,1-:: i ,:~:,_.! .c, ,i'i pet ;:;',CI~: i ~)·Y~~f 7::; ~;:" 'to .:' (~ :V'~~~r, i ~-':,;: ,~;.:J (i {~~'. j ~',~~.l t e '( ["I ;~, ~~; G :~.,\) fll"" ~~P B. ;'" ,~j,t J f) [I ':)f 1~ ;'1 0 Xl; i 1 ,~~ G ~~?j (::,:r ~~: ~J.'~ ;;, '~';:~·l:" p 1 i:,1 (l~;3' ;; oX ~~~: t I y 2 t~ C., G.) !Ii i 1 ~ i1'1 a :?~5f) (;:\C~\}tl:.:'3D~3tjr"j,t')tr tJ.,s.Gk ~~!1'S~ c.:t.··~'Ut(i 'V~,th ,~:f.5Ci O'40()dj.stiJ.10~i i~l ~ater0Add i UIZl ti0n or sod r ~l } 10 C~Cofell.~.in~s~(JpP0r ~O].uti0n~aIlci ~f'Le~ m:~"~in~a~j the dr' c ,;~j. (,l r; S c::l. ~.~'~;i ~)~J 'iJo ~~ r (1W' dr- ()'p £3 ,~.. "t £.i, or: i tr,l~j t?$ t ~;,r:g t ,L1fj t.hE; liq'!Jid. ftft.s!t 7;'~,,·";i'l ,~jJd,(~l.t:~J.\7):~l~.Vv~it!'l8€,r!(.:.::iti"\:,e 15;'tnl1.1S 1.1,jr l~;~ .~~"".' •.~~. r',.lJ,;~1..l .1).':; !.~ r.·t .."l'! ;. ..;; 'V"" ~::,,,.·,t v.;...!.., ... ,,,.lJ, c.' "F?.rJ :"\'..."~, t'" '~' lJo,I~'~h.dt,: ...... JC;;:.,.t ti~' t:~ ", .../:1..:..:,,, It "'~'~·l·i f"i l' • ~..:.. \ ...... n('h'::... ,j",. -:d~).:.:,t. ,,;~ - ),"\I... ~.·J t",·~ (,")).';, ~.~ e a. ~ ;J8Jper h~~ ~ -t ':"'" ~ r ~, ., ....... ;,;.(,.t .. ,.... L",';;)/. ,_.' • .1. the flas~~ to tl)G m8t~k W~t~, aietill0d wste!'~~'ilA pre~if)it~~~e shol)ld stll,side rap1dlY?].B~ivj,1:~ a pe~f~t,tJ,y cl,0~r ~clorle8a li,qtlj.duIt i~ imr.J Or' t H~~:! t t:~i-i~~t, t t .1i q'~).'j 6 ~~:~~ ·t:} Or ;. 1::' .1 ~.l\~' ':..~ c' \ '..".~~.,':.lJ~~). j~(; ~,\t (.~ f2; t tiA. t ,a.:n ::ft- ~<C;' ;)g ,f:~ () t E: 1}{ a 1. j« !~JJ,I~~;' t, :)<J.n r'l .~.~d ,~~ d ,~, d ,:~, ft; :?: C ~r...~,"j~n 1:3 {:i ~j, t· :.,~(,)t t 11~' r r' c e "l p: t;D,'t~?::l E.1J.~.:;t1;~1.f: D, ~iJ,C?,f,: \b!:;tDrd~1i fill~l."~lg ::rl'.1J flEtc,l·: ·t·~ t~1'Z: ~nSY'k~t:1d~~ a lit1::e ffi0r·c~0~~~r 0u,~~,prlat3~al~~ ;~0r~ to ttJ~ ~J~\,·t~al f)oint R~ain l~~ (~'! :,:}. '7,,~ .~) '~~J !~ 1 ~ ~;t' '~h.1'j~" () ~J;6,~".~ ::t./ rot :':~i ~! f:~ 1,),:t 1 tJ 't"t t c;.; ~~. t t :L.i,.; l,~t~~!;j l:'::) 'L; r .:~ l~:,!t:/ ~ :~ (1 ~~I:1. ; .. i q tA Y.. d t t"11,'" ';:';~.2 ~l ~o} ~~Jr d r-:\" f' j;, ~L-:;<~;~" i,tl t ~,)a d ~.~ tV' f 11,,~,~: t.~~h·:~ t~':;~;t ,~rri!:~,~~::L"C i <;~';~ '·"·f· :~11 ~,. r;;., r):~i,Z~dr' Jl' b'i],:i<i~:,o~ t (~,~,rl~1I;) ~~, i'iC pr ?~·F.t~t{~{~" l'fJ i Ii.;: ';~':~lrl~~ ~':'; r' i·.~ ~Jt :t (} (~I,. ri-~{~~J.!:1U.;,." $ r~c:"'~. n rat f11. j!~ :~~ c ',.(: ~, F Eil~~li. ~·1~~;:'1 C:) P'l,": n't solutio~~and 1~ (J .. (:~7Gh!~nist~1At~'atG aolutio~~in'to a sui'~ebl~re~'3 F- t 1":\ r' 1 ~:'I { d ~;.~l.~;t ~~; Vi ;~~ t 1"1 ~':~) G !}:~:1t J3; r- b~rl·j t;, ~3I~:J~i;, t () j:" ('J j.l i 1::;:0' r: .:\ d~l ~j.x~;.j,; 'r" 1 y 20 r;"i\~,:".~· ~h<?i ;'cilk f3iJgFir' ~~t<i.utj.()n ~H:;i ~~!ea'~ t,.:~ bot:l.ir~g as r'fi,~Ji.'HY a~ p0~~it)~~~~006tf.l)t)a to t~o1,1 r~~ 8i~ mi~utfl~oAil')w ·tha ~rGoipitate 11 !;\ to sUb~i,d~ a:~~ if D.;Y1Qti.r:: ~ r~ I~ ",~..:",j-.J: tot fJ u g ~,i.~. "'1' 1" ~''~.i.~t.:· ::;, ......·F~.;Jtti, ,;.~. " '% - '~' "1 J., ~' :~.~~}.4. •.l"i",>~~ eaeh additinn~until t (=~":,i"n:3,.~Jf{; •.r~:"'~~~: h el't' fe"f ~':'~Ol)r:f~l';~ • . 1: ., ••• ', ~ .• , .. ""fJ :~3,'f:' .. .;, liquid til~ jJC~ 11.1 ': () i {) rJ ~'J8.[1, t)a~ a blu~ ~010r S~ insuftioi~~t ~) ~;~r:.~rJ ~o~~.ij dt,:;r J ~"'l:;"1 )'\r"i:"I'> ( .... ",.' (..... ··:l.I,~;' ,.~:: a t 1(3 h v, ...... {~ i··~" ,-o,~. (,'7>1 .. a POil1t i8 ~~~~l'f~&~t}er3 t :'.'. €~ li'''~!'1'f{~ " "':1 ~~",/< [~l " '!~1;P~;~ ~"1G.t ~Jn 'rh .. t')~"·""·.1h \o. J ~"'~.~::, .. rzt "C'r~ ,.':,;:'N , ~f,l''i.ouJv!)LtJ,.L\4t ~:. ~ r( r., r. j,t '~'~'\l ""~:,,~.if,\v' ito ::; ,:,r1t :~ r~tlt) I-,.~ i~ imp0B~ible t J i q u. i ~ ~.;.'. b 1 ~),t2; ~)~' ,i';t':~i ....',~~ :r "i'O,,' ..:,"~':'~--'·t"-'"~.', :.1, ' ~ .,1 "~<, ~~i v·,-~ '"I' ~'~'J." -; ••, ""1 ':'_..\0 ;J r:.1t ~; Ff j, I 1:. ~~Xf. ~l(;'·f·\f";~ ,tZ'; ..I,. t {) to""1· :v 0"1 to BI ;!;e ...,€.~&;nii!f'i ,~." " "~" l~~ t!1G tj,ltr2~b in ~ t0~t tU~G ~cnt~i.~liD~{0ns Cg{Jr·~~eti~ aeid~and a t" ~,~'r dr ~}~.:fj c~?p ('}t f:~::1 ~ 1:~:'Y~it!F' T'T;' 0 (~ ,Y't:;~ ti i ':C~l r:(~ ) {7 f ()t'J·t":,i':;', '~~ i..:')~-;, -:) ~,~ ~~ f;.!1, I) c:: (t J~~j, t ~ ~j d pr e e Ip t t at e shows e op per' is s t ill that co n t a Lne d i.n t n» sol,aian.- Assuming that this result is obtained "lith :d4 G.C.stl,;,arsolution. And tnat no copper is round when a determination is made ~1th 2~ C.e.sugar solution;tn~n the quantity necessary for exaot reduction is between theso li!nlts. more determinations are made us rng 20 G.G. of tm x e d ~'ehlings s oLu t aon an d boiling ea cn t rrne e xae t Ly t) nu nut es v'rwo limits wIll tnus be Obtained whieh differ bY one fourth a G.C. The mean I between these lImits is taken as the vulume of mllk su~ar solution Which will".(,!xactly' precipitate the copper from 20 G.G.f<·ehlin~s solution.By expe r rmen t 134 rm Ll i grams of rm Lk sugar nave boerrro und to preclpitate eBactly 20 C.C.Fenlin~s solution,and this w8i~ht is con t a i ne c in the v o Lurne o rs ug ar solution used.By a simple calculation the per~entage of sugar In the ffi11k 1S found. SlJppOSe 24. T2:) e.G.were the mean above referred t o j trren the aalculation wlllbe as follo\ ... s;Z'~.l;·>'j G.C.of a T - 10 d:&.lution,repl'esent ~.4}25 G.C.of ~ure m~lk.therafore 2.4125 G.C.uf ~ure milk oontain .l~ milk sugar,snd 1:00 C.G.of mllk contain '.).::>5 grams,a~oordin~ to the proportion 2.4T25: tOO:: .t:')lj,: x 'rwo j - x - 5.55. , Polarimetric det~rm1nat1on of milk sugar. Pla~e exaotly 50 G.C.ot milk in a too C.G.~ee.suring flask,add about 2 C.C.~~ Millons roagen t an d (i1lto the mark .... 1th water,Allo'" the pre"if;ltste to SU.b'side,filter a portion of the solution t r.r ough a dry filter p ap er j and polarize. Determination of fat. The following method dSfisnding on the rapid se~aration of th~ rat from milk,bY reagents anJ the use of tho a8ntriruge,gi~es results sufficiently aeourate for all ~ractiaa1 i:i lJr'poses. Apparatus pipettes Solution PUEel rAquirod.-~ centr1fuge,~lth graduated milk bottles,t~o 5 and T 0.G. t. Gonslsts • oi1,37 GG. wood aloohol,I3 cu. A~id hydrochlorlc,~0 cc. SolutIon 2.eonslst1ng of sUl~hurl~ aCId The sample should be taken from the middle of the m i Lk ang or nul'S' ing,as the fIrst milk is r1dher and the last poorer than the 8vsraye.~ co.of the s8mpl~ is introduced into tha milk bottle by maans or the pipette;one cc.vf solution l.is added and shaken bY hand. Then by ~earis of a large pIpette solution l.lS added little by 11ttle w1th shakIng,until" the buttle is filled.lt is then ?laced in t n e e ent r t rug e and ;vhirled for one or t wo mt nut es when the fat ris~s to the top in a olear yellowish layer,and can be read off In direct perc~ntages.lf the should be vary rich and When examinin~ cream dilute withwster end mBke.pr0~er corr8~tions. Yhe great mass of the organic constituents of th~ animal body consists of amorphous,very complrx sUbstanoes.of high maleo lIar weight,eorHaining nitrogen.'lhes~ sUbst8nces"'hl~h Fire classed toge t t her In ca I Le d rne PRO'n~lNS;are either true t ds corlies closely l'~i8tlBf:lntarShe~.thegroup a.re called !Senerically the protein sUbstances,although In a few cases the term 1S used to designate in a s~ecial sense the proteids. An elementary analysis of a protein WIll give the followin~ average result. c. ~O to ~r. ~er~ent og e Rgr-.Up p h.? to 7.2 N. T'J to lB. o. 21 to t~ H. r o e a j or- • • • s •• [j to 2.5 • • The quantity of nitrogen will most often be found very close to 16 percent.,so that a mUltipli~ation of the wei~ht of nltrogen bj a factor betwef)n b •• )'7 and 5• .s'),0suall,Y" oLos e to t~.2:).Nlll!Sivf.1 the weIght of the protein under examination. No mo le cuLa r formUla has b8(1D assigned to tho proloins.'i'helrnolec ui er \'IEu-ght has been cal~ulate(t to be aboutU)OOO. A eons ider'!.t a on of the possible .ariety of stru~tural relations in so large ~ molecule explains the d1ff1culty of rindin~ a JOnstltutlonal Corrou ula for these bodies. General propertiese "I'he,)' are as a rUle,arnorphous,non .1iffusable, colorless,odorleas f.lnd nearly tFi.st~less."rhey ar e variable as to solubility.They are all opti4ally a,t1ve t~rnin~ the ~18ne of polarized light tQ the left. When prot ~~ids are aoted on by su~erheEte(t steam, r arments ,by -s ci d or a.lkall,certain decvmpos1.tion products are tormed, var)int' ''/lth the ag en t ,and the eond r t rona under "7hi~h it aets.'l'hey all r es uj t in the format ion of simpler eompounds ,creak a.ng downthe COmdlllj;l tad protein rnolecule.the process being spoken of as cleavage or splltting.An example of a cleavage process taking place in a sUbsyance outside this group.is the alcoholic fermentatipQ uf Klu~ose. ~ .......... - G H 0 ~tj'..,. .:.:;:-~n:: .... 0 ,> (' O _ M·' .<..~ When the sfJlitting pro~e8s is accompanied bY the de,:wmposition of water,and the taking up or its ~onstituents it is known as hydrolytic cleavage;an example of this form Qt cieaYa~e is the decotjpositiCJn of fats by steam, ") I :t.j S ~'11 0 ltr3~P2 )3+:-1 H~O OH ~r~( 011 ) 3.. ~:~ C H IH . .. 0 :.1" ..d • .)IJ. cleavage. are i~portant in metabolism,a.nd are most frequent 11' met with the process of digestion.In those chemical Changes conver t ing complex sUbs t anees into 8J.m~ler ones, the at urns ent ar '3stat~ of sta~ler eqllibrium and satisfy stronger affinities,~un) veTtIng chem1cal potential ener~i 1nto living anergy. '!'hese in WheT'la proteid is treated with an alkall;part of the nitrogen is split off ~s Rmmonia. ~fter cleavage with hydrochloric aeid, nitrogen ean be obtained in three forms,-as an~unla,as dl-amidO compo~nds,precipitable by phosphotungstIc acid,anct 8S monoam~do acidS,not precipitable. A part of the sulphur separates on tOllIng with alkalies,as sulphide,and uan De deteeted by lead aoetate.What remains ~an only be detected after r us i on WIth OXIdation rm x t ur e s ( See properties and reactions of the constltuentsof milk.) In most ..r-o t e i ds the quantity of sulphur SpIlt off 1S about half of the amount of total sulphur.The proteid Doleaule therefore contalns at least two atoms of sulphur. When p r-ot e i ds undergo hydrolytic cleavage, they r i r s t form proteid bodies of lower molecular weight,vBryin~ 8~curding to the proteId aated upon,and the nature of the decomposln~ agent. In the ~resenoe of acid or alkali,bodles InsolUble in neutral solution are formed,known as a c i d or a Lk e.Lt al b urni ne f'he ~roteolytl~ enzyme cause the formation of albumoses or ~ruteoses and peptones,Purther cleavage SllCh as reSUlts from lOeB boiling wIthstron~ aaids,the prolonged R~tion of enzymes,Rr oacterlB,Bives rise to the amidoacids tyrosin,leucin and aspartis a~id.On far rea~hing decomposItion the hiaton bases,lysin histidin,and ar8aninare Obtained. v GLA,55 lPTGA'iTO~J OF 'fHF PPO'n~TNS. A classifioation of the protelns,based on true sClantific prin ciples,is impOSSIble in the ~r8sent state of our knOWledge of the s uo s t an ces sPor convena ene e an s t uo y the," are d i v rue d zn t o three groups.Simple proteids,Gompound protiects,and Albuminoias.~ach group is SUbdivided. s lMPL~ 'rne PRO'I'i~: IDS 0t(~.1H D;.;TNOUS BODl RS. Lca I reactions of the p ro t e i ds are d1vided Ln t o two classes,the precIpitation and the color reactions. A. Precipitation reaotions. 1.-Coagulationtest. On heating a proteid solution,lt is ~hanged the temperature necessary dependM1ng on the proteid present,and with favorable external conditions18s,the presenoe of neutral salts,and the proper reaction of the solut10n,most proteidS se~arate in the solid state as ~oagulated proteids. anaj.yt An alkaline proteid solution will not coagulate on boiling,a neutral solution only incompletely,so the reaction must be acid fD for coagulation!The neutral liquid is boiled and dilute Bcetic acid added carefullY,boiling before adlting each drop.Tf dilute n i t r t c aCi.d i~ used,ad<1.after bo i Li ng abou t one drop of acid fur j each cc.of solution used. if too little nitric BOld be,add~Jt~ soluble comb i.nat aon of the a,oid and the proteid is formed, which 1,s precipitated by more acid.A proteid solution aonta1ning ~ ~m~11 quantity of salts,will require the addition of a rew drops or saturated solution of Ha Cl,befor~ boi11ng,or thO heatin~ test may fail,especially with acetic aeid,whon the protB1a ~olution is dilute. 2. HaIlers test.Place in a test tUbe Hbout IOao,pure nltr1a aoid, allow the proteid solution to flow 1o\1n suoh a manner that the liquids do not mix. A White opaque rtng of Ijoal6ulated protold forms at the line of junotion. 3. Precipitation by metallic salts. Plaoe ) co.uf proteid solution in each or three test tUbBs;a,b,and o~~c B,edd about Zor. ,oppBr SUlphate scf ut i onvr o b,alid eas i e or naut re I l",aa a ce t a t.ej t or c,add merouric chloridew~'heau reaetlone explain tho UDe or vroteid solutions as antidotes In eaSBS or poiaonlng oy these mBt~l~, 4. To 5 co. proteid solution add a few drops of aaltla 8ald and som~ potassium ferrooyanide,a voluminoua preelpitate 1~ formed. 6. Saturate a solution of protoid with ammonium qulpriMttf! -lit pra,,!p itate is formBd,exeept in a solutiun of popton8A Picrfo,trichlorao'tio Ph08photun~itia)~ho~phomolYba1c Gnd tlnnl0 aoids,pot.e,ssium mer eur i e 1od1de,~nd al'H).hol)~ll t)r~"lplt.,ti:) ~roteid soiutions,under s~edial ~und1tionB. Coagulation is dist1nguish~d from pr~oipitation,ln b#lnij th0 result or R ohange or alteration or the proteid 1n its JhemldBl an d physioal prop"rties,usually man1rt'8t~d rn iti "tHftn~{, or Soa,llbi11ty. s, Color re8~tions. Xantho-prota1e reaotion. See proporties anrl r0BattDn~ of the ~gnstituents or milk. Wlllons react1on;aa above, Adamkiewioz reaotion- N H L1~bermanns reaction H Biuret reaation.-To 5 OGJof proteid solution add an ~qu~lvolume or sodium hydrox1de,and after mixlnM ndd ono or two dru~~ or ~ dilute solution or oopp0r sulvnet9.-A v101~t to pLnk color 1~ obtained aocording to tn~ amount of ~opp~r ~olution,~nd th~ nature or the proteid used.It mBy be n~e~.~ary to h~Bt the lolut1on,to Obtain a 41stln~t rhaotionq Any of these color react1on~ 04n b~ obt~ine4 w~tn oth~r .ub.t~no •• but the proteids alone ~111 r~upond to Bll rlv~. Millons and the xantno-prot~lc reft~t1on ~r~ ~1v~n by ~ub~tane •• Of the ..,henol group and indicate th" pra80nce or i1n itrOm~tLo nucleus 1n the proteid moleeule.A~amk1~w1Gzs r~~~tton l~ con.ider- ed a furfurol reaotion,brOU~ht about by a ~arbonYdrAt~ ~roup 8. ~ell as an aromatic group in the prot~id.Ll~bermftnn" i~ 3 furfJrol reaction. THe b1ur~t r~a~tion 1. ~lv~n by ~3v~ral nun-prot~ld Mllbstances and seetns to indicate the r~re."nf1Bor fJ.t let.l~t tWQ fJONH .. ,. 2 8S groups,united to a .tn~le C or N atom,~r on& ur mor~ CQnk ~rouV. united in open chain. GI!ASS 11" 1 CAT r 0\1 0;<' PFO'j'F:IDS. Those proteids ocauring formsd in the animal body and whi~h ~an be isolated from it without losing thelr origInal properti~s,are call ad ?"TA'fl V f'~ PPO'I' E 1 DS. MOdiflcationsobtained by thB.action of heat,chemIcal reagents,and proteolytic enzymes on t h e na trv a proteIds,are ;~alled DFf'~IV';:L) PFO'ff?TDS. The dIfferent SOlUbility of proteids,&nd the effect of certain neutral salts on their solutions is the baSiS of the following clasSlfication. 1. Protelds siluble in al~ohol. 2e1m and Gliadin,re~resent class,and are of scientific interest only. 2. Proteids solUble in divided into two grou~s. water, insolUble in alCOhol. this 't'h i s c Las s IS a. Albumins These sUbstances ara solUble In water,Rnd era nut precipitated by weak aCIds or alkalles,or ty s8tur&ting thelT solu tion with MgS04 or NaCl.'fhey are preljlpitated by large quantities of~min,~ral !'t{nds or m.~tallic salrS,Rnd by satl1ratlon of t ne i r SOlUtIon :vl!th ammonillm sulpnate."hej ate b.} I1da"t,ln ;;oei5ul&too nH1 neutral salts. b. Peptones,are s!Jbstane~ls rl:3sultintS from the dig\1stlon of proteId 'fhey are not preoipitated bj( saturation1· ... ith ammonium S'.lliJhat':l,and are not coagulated by heat. presence of 8. Proteids solUble in dilute neutral alCOhol and in W&ter. This class inoludes salt solution;insolubla the globulins,vitelltns,and In the hetero)pro) Important glObulins are 1,acto-globulin of milk,serom globulin of blood serum,myo-globUlin,mY~sin,muSdRlin,mYOSinogan of muscle,fibrlnogen of blood.1he vitellins Inalude the crY~tallin of the lens,and vlt~llin of th~ egg YOlk.Hatero-proteoses ara teos.s.'J'he" formed during digestion of ~ruteiJ. The glObUlins and vitellins are easily distin~uished from hetero proteoses,by being ~oagulated by heat. GlObulins ~re pre~ipitated When theIr solution is saturated ~tth arnmoni.um SUlphate,magnestum sU1fJhata or sodium "hloride;thdY :1.1"'" also precipItated When the solution is half saturatt!d with aminon i. urn SUlphate. Vitellins differ from glObulins in not being salted out The hetero-proteoses will be considered in oonnection gos t ion. 'fhe With var ious globul ins a.nd v 1 t ell ins are cons ider ei.t tissues of WhiCh th(~.y f()!")IJ iJart. fhe In NaCI. ~ith di- by c onne c t ion 4. Proteids soluble in dilute acids or alkalies,insoluble in aleohol,water,and salt solutions. Alkali albuminate,is a variety of deri~ed proteid,obtained when native proteid is 83ted upon by an alkali,1'he ahange takes placo slowly in dilute solutions,at the ordinary temperature,but more rapidty on heating. Acid albuminate,is obtained when a nati~e prote~d is digested with dilute acid. Alkali and a~id albuminates have certain propertias in ~ommon.'(hey are insoluble in water and dilute'sRIt solut10n,but eas1ly solUble 1n water in the presence of' a small quantity of 8cio or alkali. ~his solution does not coagulate on boiling,but 1S ~recipitated on neutralizing With acid or alkal1.A solut10n in dilute aJid as ~omf is completoly preclpitated bY saturation ~ith ffia~neslum sulphate, ammonium sulphate,or sodium ¢hloride,but a solution in dilut~ alkali is not precipitated Although agreeing 1n these reaations.ao1d and alkali albuminates arc essentiallY differen,.In the modification of a proteid by an alkali the chemical ¢hange is essentially different from that oeouring When the proteid is acted on bY an acid,and the products are of differant natures."he alkali albumlnates ha~e de~ided acid properties;they disso~~e in water,on the addltion of calciw~ carbonate,with the e1imination of (~arbon di-oxicte;a ~roperty the a3id albuminates do not possess. Dilute solutions of alkalles act mor. enor~eti~allY on proteids,than do a1ids of corresponding dilution. Whep treated with alkaliespart of the nitrogen,and often part of the sulphur,is split off from the proteid;'for this reason we can ~onvert acid albuminate into alkali albuminate,but oannot reverse th~ process.When a solution of a~ld albuminate is made in wateT,bY the ald or a small amount of alkali,no alkali albuminate is formed but a solUble ~ompound of the a~id albuminate and the alkali. When alkeli albumin is dissol~ed with aoid a eompound of alkali albumln and acid,but no acid albuminate forms. Anti-albumid,is an acid albuminate obtained during a rapid digestion with proteolytic enzymes,or by boillng proteid with dilute. sulphuric acid.snd is characterized by its resistanoe to dl~esti~e fluids,and by its ne~ati~e reaction with ~illons Teagent by DYs-proteose is a modification of hetero-proteos6,obtained leaving this material in contact 'vith water for a lon~ tlme. 6 Proteids InsolUble without decomposition. Coagulated proteids,may be obtained from native proteids by the action of heat,aeids.alcohol &c.rhe nature of the prouess of ~oa~uletion is unknown.Ooagulated proteids are insolUble witheut decomposition. BlOOd fibrin,is a coagulated prot81d ObtaIned by the con~ersion of rt~rinogen of the blood into fibrin by an enzyme. CO~POUND PR01F.lDS. When a simple proteid is boiled with a dilute acid or alkeli,we obtain by the rirst hydrolytie oleayage.a sUbstance of simpler stru~ture,but still proteid in its nature.By repeating the aleavage we will e.entu8l1y obtain a non-prote1d.When a oompound proteid is treatad in u similar manner,we have formed by the first splitting,two sUbstances,ene proteid,snd the other non-proteid in its nature.During the splittin~ of the compound proteids,the simple proteid formed ia immediately con~erted into acid or alkali albuminate,depending on the agent usec.1in the hydrolysis. All a"id or alknll albuminates bein~ id~ntical in their properties,a . classification of compound proteids must depend on the non-proteid results of hydrolyais. Haemo~lobins,are compound protieds yielding a molecule oontainin~ iron.'j'heyare all solUble in water,and ooagulated bY heat with decomposition.~hey are beat studied in connection with the blood. GIy~~proteids,ar~ those compound proteids yielding a proteid,and a sUbstance ~apable of redu~ing oupr1c oxide. Muoins,are secreted bY the larger muouous ~lands of the bodY,and will be considered in conneotion with saliva,which a true mu~in. ~ucoids or muoinoid. resemble muoin. in all their propert~es exeept in being preei~ltated bY acetic aoid. Amyloid ocours pathologically in the splean,liver and kidneys as infiltration,an4 in .erou. membranes as granules with concentric 1~yer8.Amyloid y1e1,. QD boIling with dilute hydroohloric acid, sulphuric acid and a reducing sUbstanoe.lt is split by the action or an alkali 1nt8 prot_i. and chon4roitin-sulyhUri~ aci4,an etherial sulphurio 80i4 or the oompQsttion C 1~2("}'J°l:4HS05 ~ueleo-prot.ids.are compound prote,ids ¥ie.ldi~g on hydrolysis, nucleins and a simple proteir."'I'henueleins: are especiallY resistant to the action or pepsin hydroohlorie ecla.ano are usually Obtained as an insolUble ~es1due after tn'e 4igest ion of nucleo-pro teids With t'hl. r:eagent. 'I'henuc~eo"'prot.'icl .. can be loo,~ed upon as a combination of compound and s~ple prot.id.~he nu~leins bein~ eomp!ex molecules re,:;embling 4ompoundproteids.,'ne nue Lerns are (1i~ided into two clesses. Cell nU~leins,Whioh yie14 on hydrolysis,a proteid,ortho-phospnorio acid,and Xanthin bases;occuT ohiefly in the nuclei of the cell,but are found in the protoplaam,and may •• pas~ into the animal fluids on the destruotion or the cell. Pseudo-nucleins yis1d on clea,a~proteid and ortho-phosphoric acid, but no xanthin base •• ~hey are considered to be deoomposition products or the true or cell nucleins.Casein and the nuclein of eFK iolk belon-s to thu. gloaa.'l'f\u lel.t~~r~ubiltance contains ar on In additi~n to the usual constituents of the group. Nucleo-histon,is a variety of nueleo-proteid,yielrling on hydrolY sis with .8 percent hydrochloric acid,nuclein and a proteid SUbstance soluble in hydroohlori~ 8<'id an d wh i ch differs from other proteids in being insoluble in an excess of ammonia. This proteid sUbstance is known as HtS~ON. Phospho-carnic aoid,is a complex substance combining the aharac teristi~s of the nucleo-proteids with soma of those of the glycoproteids.It yields on hydrolysis,in addition to other sUbstances~ phosphoric acid,a reducing carbohydrate,and a peculiar proteid, carnic a~id. ~LBUMTN01DS. 'i'hes e are protein bodies, whose general prop er t aea sugg es t them to be anorna.Loussimple protei •• 'l'he,occur ch'ierl y as cons tit uents of the animal skeleton and or the skin and its appenda~es.They exist as a rule in an insolUble condition in the organism,and shOW marked resistance to the ordinary proteid solvents,and to reagents in general.' Keratins,oocur as the chief oonstituents of the horney structure of the skin an d its appenda6es.l\eratins o-re characterized by containing proportionately large quantiti.es of sulphur,part of wh:i.ch is in loose oombination.On dae~ eleaYa~e,the keratins give the s~ne products as the protei4s.1t is probable that the keratins are derived from proteids bY SUbstituting proteid oxygen,bY sulphur. Keratins dissolve s10"'IY in caustic: alkalies,especially on heating 'i'hey ar e not disso}1red bY pepsin b¥droohlor a e so id, or by t r yp s in solut ion.'i'heygive the xantho-proteic Millons and the bluret r ea e tion. Elastinloccurs in connecstive tissue.'l'heligamentum nuchae contains mUch elastin. On deep ~leavaKe elastin yields the same products as the prot teids,except that glyeocoll repl~ces aspartic ~cid.The molecule contains a very small J:)ercentage of SUlphur. Elastin is insolUble in strong alkalies at the ordinaey tempera' ture,and only slowly..on boiling.lt is very slowly s oLub Le in co Ld sulphuric acid,but easily dissolves in Warm nitric acid. Gold hydro~hloric acid easily dissolves elastin derived from the aorta, While elastin from the ligamentt~ nuchae is disso&ved w~th diffi cUlty.F.lastin gives tne xantho-protei4,Millons and the biuret reactions. Collagen,is the chief oonstituent or fibrous tissue,and of the organic portion of bones.noll&~en of bones is called ossein. Mixed with other materials collegen occurs in cartila~e as chon drigen. On boiling with water,or more redi~y in the presenee of acid, .ollagen" is oon.erted into gelatine;which when geated to 130 c. is transformed into collagen. Collagen can therefore be considered as the anhydride of gelatine. Gelatine on hydrolysis,resembles the proteids in most of its products,but differs in yielding large quantities of ~lycoooll,and in not producing any tyrosin.~his last difference is important,and is accentuated by the products of the putrefaction of gelatine, which are free from indol and ska t oI s t'ne properties of gelatine will be further studied in connection with bone. Reticulin,oceuring in the reticular tissue,and Skelatins forming the skeletal tissues of invertibrates are members of this group. The cleavage products of the protein sUbstances ,will( be taken up,in connection with digestion. F'A't'S. Pats are widely distributed constituents of the animal organism occuring in every organ and part of the body.~he bone marrow is the tissue richest in Fats,and the intermuscular connective tIssue the fatty tissue in the abdomen,and sUbcutaneous connective tissue are the most important deposits of fat.ln plants the fat is found in the seed,~ruit and oocasionally in the roots. The fat of the animal body consists partly of fat absorbed from the food,and deposited in the tissues,and. partly of . fat formed , . ' '. in the organism,from proteids and oarbohydrates.When food contains an excess, of fat the exoess is stored up in the fat ty t issues and when the food becomes deri.ient1n rat this store is drawn on .In . . starvation no tissue deoreases as much as the fatty.'l't:'le fatty tissue of the animal' body is a depot Where,durirtg proper alimEmtation,nutritive material of great importanoe,is stored,to be given off as it may be n8eded. The animal fats consist chiefly of the compound ethers,stearin, palmatin and olein.The proportion of each present,varies in fiirrerent fats,the fat of children is relativelY richer in stearin than adult fat.ln solid fats stearin and palmetin havethe preponderance,and the quantity of olein is ::sreaterin t.hemore liqUid ones.rhe solid stearin and palmetio have loW melting points. These ethers are triglycerides,formed by the replacement of the hydroxyl hydro~en of the tribasic alcohol glycerin,by the fatty acirl radicles.tn certain rats,particularly in milk fat,gly~erides of butyric caproia,capryllic and capric acids occur,with the first mentioned three.In addition to the the stearin,palmatin and olein, the animal Cats also contain the gly~erides of lauric,myristic and arachidic acids. While glycerine is the alcohol ehieflyoccuring in the animal fat,certain higher alcohols have been shovm to exist in ~.; the oo dy , The fats hydrolytic are oharacterized by the acia and alcohol formed by cleavage of their molecule.'fhis cleavage,whieh may be produ~ed by f9~ments.super-heated steam or caustic alkalies is called saponification.The term is used in general to denote the hydol y';::~; s[.'1.:i. t t ing of a compound ether. The Gynthesis of fats from their component alcohols and aClds with removal of water has nerer been made artificlallY,and requires tile 58iective action of the liVing cell for its perform) ance. When exposed to the air for a long tilllfJifats are ,t£composG,Lj into fatty acids and alcohols.The fatty a.ids arc oxidized,producing v oLat i16 c ompoun ds of unpleasant odol"'.l'ats so de e.ompos s d are s a Ld to , be . rEi.·"[lGj.Qc Free fatty a c i ds occur in v ar Lous proportions in t h e rae of th~ body" and (i. e formed dur- ing the digest ion of ne u t r a I fats, Uncombir, ed alechols are very rare,the only oCCuring io sUfficiont amount to be of interest is cholesterin ChcJ.esterin,is an unsaturated aleonol of the composition C')'7H/, "-!' _9H, .",0 req~ir'ing the addition of ten atoms of hydrogen to saturate its moI e cuj o , It is a constituent of all ~el113 and is (cunei in C:,J!'t1binaileD wlth stearic and palmitic acids in the bloOd. skin and b~ain Chclesterin fats arB very resistant to the action or putrefa.etive b a o t or ia; and the oc cur ance of rnes fa t s i'l combina t j~.on wa t h the keratinf3~pl'e;.·ents the deeomposition of t r.e skin sur ree e of the livin15 bodY,bY the bacteria whi'Ch are eone t ant t y pree~,l1t on it. Chole::iterin o c cur s in large quantity in the bile and i6 the c h i ef' constituent of biliary calculi. Its properties and reactions will be given in connection with bile. The simplest.fd~m in ~ombination with in sPSi"JJ8.cetti;which alcol1C:.t of fat is one consisting of a monacid al~ohol a monobasic acid.Such a fat is eetin oddUring yields on hydrolysis palmitic a c a d and cetyl 0 ,-; x> ,.0 C i' H II;;' ~3'L 2 16 33 catin W A~or ~U~h SUbstances ILL, acoid m'l·tl""b'''''l'· ~., a~ •.. c, ... oS C H COOH ~ C 15 31 Palmitic acid H CH OH 15 31 2 cetyl aleohol. only one form of combination d It' , an mu I-aCId a.lcohols are is possible. conside . .ed, the of combinations are multiplied in prorr~ion to 1 bl' , . ,·'--,!.l,-,,, ~. ep aeea e groups an the acid or aJeoho'- .'I'he com•. LILD~"1'ci()I1 of mono·-basic acid and glyeerin allows three :V£tTiatons as one., t VIC' O~~ three of the hydrOXYl groups ~\~l;,the "v glY,,:c:~in are replaced.The combination in WhiCh allthree Y'epL;.eod forn'ing a saturated compound is the one oc~uring j.n th'eOiC f)fJ,'::"sible t h Co "''''~''· .. variety c.r nf r ~re' bOdy, " --'7;;.;;;.;; a tri-a,~id base is combined in molecular proPoi'tion with a :,c aci a neutral sal t is ordinarily formed. Under certain 10 "~Lj(.n t 08, wi th or ganl.~ ula t er ial ,the 1" esul t will be the formation 01 ,a compolled haVing at the same time~ the propertiE:s of salt acid ~11n. 'baseo ~ \:?l!en l :: ~_l'~~,~,~ \ Glycerin phosphoric acid is a compound of this nature obtained by the combonation of glyoerin and ortho-phosphoric acid,with the elimination of water.~he reaction is represented in this equation c H (OR) ...PO (OH) ~ 0 H (OH) 3 5 3 3 3 5 eo (OH) 2'0 2' ..r H O. 2 1he hydroxyl left in combination with the glycerin radicla can be replaced by acid ra4iclas,while the phosphoric acid hydrohyl.is replaceable by basic or alcohol radicles. Lecithins are phosphorized fats occuring in all organs and tissues of the body,particularly in the central nervous system. fhey are formed by replacement of the ~lycerin hydroxyl of glycerin phosphoric acid,bY fatty acids.and the hydrogen of one of the phosphoric acid hydroxyls by the residue of the complex alcohol cholln.Distearyllecithin is represented by the formUla 03H5(OT6H3702)2°cl~-002H4NOH(OH3)3. 'l'Hesynthesis has never been accomplished, but the s t rue t ure of the moleoule is tnovm from the resUlts of its decomposition. Distearyllecithin yielding on hydrolysis cholin,stearic acid and glycerin phosphoric acid. Cholin is a complex aloohol.belonging to the group called ~ydramines.tt can be looked on as ammonium hydroxide,in which three htdrogenatoms have been replaced bY methyl, and a fourth hydrogen bY the combination with the di-acid alcohol of ethene. Closely related to oholin are neurin and muscarin,substances rei SUIting from the putrefaction of animal matter,and belonging to a class of SUbstances known as the animal or cadaveric alkaloids,or ptomaines,on account of their similarity in Chemical composition. and physiological action,with the vegatable alkaloids. Neurin,can be Obtained by remoVing the components of water from cholin.Poisoning with this sUbstance,gives ri~e to symptoms elmost identical witn those of Tleus.and suggest the possibility of decomposition in the intestine,in this condition,resulting : in the formation of neurin;the absorption of which is the daUse of the symptoms. (Auto-intoxication.) Muscarin.more poisonous than neurin,can be obtained by adding a atom of oxygen to its moleCUle. F.pinepherin is one of the three alkaltjds.oocuring normally in the animal body.It is obtained from the suprarenal capsule.and has a marked action in raising blood pressure. EXAMINA110N OF ADIPOSE Separation of fats and connGc~~V~ tiSEUS P:~ace ab ou t 10 grams of a d i poa e t iss ue :fir efr.rab::" Y - r ;:":1I t:l C hog} t hc t hac been cut into small p i.ec es an d sUbsequent.:':' 61';:;\:.~-:.r: as finely as possibl& in a mortar,in a flask;pour upon it bO oc.of absolute alcoho,l;and heat to b,oiling over' a water na t h The greater part of the, fat dissolves. in t h e: alcohol,leaving the o onn ec t Lve tissue e t e .. undissolv:ed,.Fi.lter;bring the residue on the filter p ap er r and' wash r rr-s.t with alcohol then- with ether.Allow the ether t.o evapor at.e from the residue and: test ror proteid bY mearia o.r the xan.tho-prot-elc. rea~,tion. or b,y means of' I,til.lons.- reag en t.. Evapora t.a the. filtrate &f.1'd' \"18s.hings over the water bat.h;on c;o.oling the, f'at i c slowly solidifie.s, I~ Rub a small piece Rea~tions of Fats. of f~t on a piece of glazed paper~-the paper becomes semi-t r enspar en t • 2. '1'0 a few c.c.. o,f alcohol t;add 1 or 2 drop.s of ve-ry dil ut e caus.t t e soda and then sufficient rosolic acid' t opr oduoe an int.ense red color.rC-o. this- mi,xtu.re add an ,.~.j,. etheria.l solution of r a t tone drop of fa.t d:isscolve'd' in a fe'''''! "-. of ether.) -'}!he color of the solution is not ehanged,the {..-\os react neutral .. 3. Mix a drop, o£ r-a'~ with a small: quan.t it y of pot as s ium b is ulphate place this mixt.ure in a dry test t ube j an d heat-the characteristic penetrating ddor of acrolein is no~ieeable. 4. Heat a small portion of the fat in a test tube with sodium earbonate solution-nhe fat is not saponified.Caustic soda acts in the same way at room temperature. Ss>p.<>mlr1C&t :ion of r c t s • To 100 ce.of alcohol add, gradually !O grams of flnely pOWdered caus tic potas.h.lf the. mixt utre: a.t any t rme becomes, too hot t. cool in 3. stream o.f water.When th'e, a,loo:.nalwill not d'issolve any moDe of t.he potash a1,10\'I to' s-tand\;:and toenP;O\1l~J" o'f"f the clear sup er aa t.ant, 1 iqui.d from the: F'e"s:idU:e-. Melt 50 grams. Qif' }.a·p·d a su:itabaetre!S$,e-l wi th a lit tl&. alcohol br ing i·nto a 5@6 ClC-fl-a'$.tt:p,o:\W ~on, it t.he alcohO,licsolUtion of caustic p.otas·h;-and. heat over t,he water bath until. a dro.p of the mixture is completely dissolve4, in water. Wh.en saponifiea· t ion is complete pour the o.ontents of the flask into an evaporat ing dish or a beaker containing 500ec.of water;heat over the water bath until the aleohol has evaporated;and then add dllute sulphuric acid until the solution is distinctlY acid. Allow to remain on .('1 the water bath until the fatty acids form a layer on the surface of the liquid,and then allow to cool. The layer of fatty acids contains palmitic,stearic and oleic acids.~'he liquid contains glYc erine. Decant the liqUid upon a filter paper (the filtrate to be used in the preparation of glycerin. ).Break the fatty acids into s~all pieces with a glass rod bring upon a fliter pa?er~and wash flrst With tap wate!" until the wash water does not ~'eact acid,then with a little distilled water. Reactions of a mixture of fatty acids .. Repeat exo er tment e 1,2 an d 3 't204ll-er 1!.eactions of fats. 4. To a half saturated solution of sodium carbonate;add some of the ratty acid mixture.The fatty acids dissolve with the liberation of carbon di-oxide;and sodium soap e are formedu Cool the mixture-it solidifies to a jelly. 5. ":<ri.ng 2 grams of the fatty acids in a beAker and pour on them 100 cc~of water;haat and dissolve the fatty aoids by adding a slight excess of caustic soda-soap solutiDil.'l'.!'l;·-e f<>llowing reactions are to be made wii. th small portions of this eolution',vhile it is still warm" a. Add to a small portion one cc.hydrochloric acid-the fatty acids are liberated. b. Add to a small portion a solution ~r calcium chloride-the mixture does not foam on shaking. e , Add to a third portion lead acetate -wnr t e precipitate.whioh on warming becomes stickey lead plastero d. Add to a few cc.of the soap solution one or two drops of sweet oil~and shake the mixture,-homogeneous milk like mixture (~mulsion rhe soaps have the property of emUlsifying fats~Repeat tho exper~ ment but instead of using soap solution use a few drop2 of sodium carbonat/;; solutionoEmulsion takes p-lace if the oil contains a little free fatty , acid;absolutely neutral fats free from 80ia are not emUlsified. 6. Place in each or two dry test tubes equal portions or fatty: acids and fat.Place both tUbes in a beakar which 1s pa.rtly filled with water;and heat carefully with a small flame,st1rrin~ the water to maintaan an even temperature-the meltin~ point or the fats is lower than that of the fatty aeids. Palmitic and stearic acids can be separated from oleic acid,bY erYstallization from an alooholio solution. Oleic aoid oan be obtainsd in a pure state fpom the mother liquor ,bY oonvertin~ it into lead iOleate~decomposing this salt with hydrouhlorio acid in etherial solution,purifying by repeated extraotion of the etherial solutian with water,in 'a separating funnel,and evaporating" Separation of Glyoerin. The filtrate from the fatty acids contains gly¢erin~potaBsium SUlphate and free sulphuric acid.Pilter tho solution;neutralize With sodium earbonate;evaporate first over a free flame later oyer the water bath ~M; much as Posslble;and then ext r-aet the residue With 50 eCoof alcohol.After standing a short time,filter:evaporate as completely as possible over the water bath;and extract again With 25 CCQof absolute alcohol.Remove from the water bath and ~-.... after COoling pour into a small flask;and add 25 e~~or ether. Shake thoroughly; and allow to stand 24 hour s ,Most or the salt. are removed by thi~ process.Pilter;end allow t06yaporate atfirst,1n a warm pla~etand then warm gently over the water bath. Glycerin remains behind as a light yellow syrup with an intensely sweet tast e. Reactions of Glycerin. 1. Make the acrolein test with a few drops of glycerin. 2. Mix a little borax on a wathch glass with a drop of glycerin;, and heat a platinum wire brought in contact With the mixture in a colorless flame. The flame is colored green. Di~801ve the remainder of the glycerin in water;add caustio soda;thena drop or two of ~ehlings solution.On heating there is no reduction of copper- OARBOHYDRA'f1'~S• The carbohydrates form the ohief portion of the solids of plant structure. They occur in relatively small quantity In the animal bodY,either free or as a constituent of compound ~rote1ds.CBrbohydrates are ext,raordinarily important as food,serving as fuel to yiel4 heat and muscular po_ar.Any excess of carbohydrate material absorbed is deposited in the liver as glyeogen,or is converted into fat and as such stored up. ~he carbohydrates include the various augars,starohes,gums, cellulose &e. and several s ubs ta.noes obtained s yn t be t i"al1y. 'rh e y are distinguish~d by the sUffix ose,added to a root signifying their origin ,or some other chara.cteristic.AII carbohydrates are diVided into three groups:the mono,di and polysa.ccharides. MMONOSACCHARIDES,are divided into trioses,tetroses,pentoses,nexoseS,heptoses &c. according to the number of oxy~en atoms presant in the molecule.Of these groups the pentoses and hexoses are of Physiological importance,the others are,however,of the ~reatest scientific interest.AII monosaccharides are either aldehydes or ketones of polyhydric alcohols,and are known acoordingly as aldos es or ketoses.'rhe hexoses are derived from an a Lcono Ljwnos e moleCUle is made up of two primary alcohol groups in combinat1on with four secondary alcohol groups.Wnen this alcohol is oxidized an aldose is formed it the primary group is acted upon;while a'ketosa reSUlts from the oxidation of the secondary. CH20H f CHOH) §HOHCH~JOH-t 0 HeXYl alcohol CH2·0H(CHOH),,:>CHOHCH20H-~O -, :::. 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(}~i' t:l){-;"t t irJ~(;)r. j"~ c;t'!~ered7 :;;-,~.:';~~~~"~~/; ..:.f·.·-gi::~:~~~ . :i:'~:~~~ ;: f:r~:~ ~:~:~; ::i::;~o~~~N:~own ~'i 6$ M n '~.. \~,)~,j)'fU"),fr'1H;~:,-: (}H~OH(CH(}"H)4C:JlH41·!~\i~0·'~;·f';;;/;~ Cll:,::l-t(GHOH)4 = CHNNHC H ;6 S H NNHC6H5 Z 6nS -;. HZv -:- CHZOH (CHOH) 3CCHNNHCtiH5NNHC ...~·1 ~li. .. osazone. '~·l'F:. llyc.TcgenL3 not evolved but acts on another rnoLe cuLe of anil in and a.rIlIIOIli~t r<:~:"tlYlhydrazine, forming H NNHC 2 H 1" 2 65 H = H N4J ... 285 NH 3 • rhe osazones are yellow crystalline sUbstanoes;which dirfer in melting po i n t ao Lub i La t y and other properties ,in each sugar.'I'hey are very useful means of separating sugar. from other materials in sa:utlon,and from each other.fhey are of the utmost importance in the sy~thesis of sugars. On cleavage with gentle heat and strong hydrodhlorio acid,osa zones yield phenYlhydrazinA'hydroehlori~eBnd keto-aldehyde compounds,called osones; CHZOH (CHOH )3COH (NNHCSH5'2 + 2 H20 + 2HCl =. j 2CoHsNHNHZHCi'" CH20H(CHOH)~COCOH. 080ne. By reducing the osone with nascent hydro"eQ,from zinc 8cid,a ketose is obtained; GH20H (CHOH) 3COOOH to 2H:: and a ce t ac P": GN20r. (CHON) ~-iCOCH "Iha ketose is obtained in this way from an isomeriC aldose,-as in the oonversion of glucose into levulose. The monosaccharides are colorless odorless,sweet,substances neutral in reaction,radilY soluble in water, sparinglY inalcohul insoluble in ether.They are optically active,some laevo,others dex tro-rotatory:the optically inactive modifi~ations are formed bY the union of two opticallY oppoaed componants.Soma are fermentable with yeast;some undergo lactic,butyric and mue f Lag anona fermentation. Dextrose,levulose and ~alacto.e of the hexoses,anJ aribinose and xylose of the pentoeea,8re the only monosaocharldes of reAl interest in physiological chemistry. DF.X"ROSF:, (glucose,e:rape-s\Jgar),o4curs il\ large q uan ta t y in :3 nUmber of sweet rruits,Qften aeoompanie4 by levulose,Tt occurs in the intstinal t rae t n during ditrestion,also in sma Lf quan t Lt y in the blood and lymph,and in trades in the urine,and other arnimal t1ssue and fluids.ln diabats the quantity of aex t rose in the urino~may re8ch 5 percent or m~re. Dextrose can be Obtained artifidially by boiling staroh with dilute mineral acid,dextrin being formed intermediately. It can be Obtained by the hydrolytic ~leavage of other compound sU~Brs,and ~lUeosides.ln the body it can be formed from proteids. Dextrose usually ~cdurs as a thick syrup,but can b9 arystallizeG. ,It is easily soluble in water,the solution is dextrogyrate,and :shows birotation;that is the angle or rotation graduallY diminish~ .es,when the solution is allowed to stand.~he opposite action is :called hemi-rotation.The specific rotation is 52.ti in a one to .fifteen percent solution. · Dextrose reduces metallic oxides,and is easily and completely ifermentable with yeast.On oxidation it yields at first gluconic acid;th8il saccharic acid.With phenylhydrazine it forms an osazone .soluble :n ooiling alcohol,1nsoluble in water,and melting at 204 205 C. Pive grams of dextrose,will reduce 1000 cc.Fehlings solute LEVYLOSE,is a ketose and crystallizes with difficulty. Its ·watery solution is Laevogvr-a t ev r t ferments with yeast,and g i ves the same reduction tests aad osazone as glucose.Levulose can be detected by warming a few drops of the suspected liquid with a solution of resorcin in diluted hydrochloric acid{I-~),when if ·levulose be present,the liquid will become red,and a precipitate ·settle,which forms a red solution in alcohol.5.43 grams of levulose reduce IOOOcc~ Fehlings solution. Levulose,occurs mixed with glucose in fruits,and is formed by the hydrolytic clea\age of cane sugar and some other carbohydrates.In Extraordinar~ cases levulose is found in the urine of diabeties. This sugar is of special dietetic importance in diabetes because of itq being redily assimilated. GALACTOSE,is an aldose,obtained on the hydrolytic cleavage of milk sugar,and some other carbohydrates.It is alsoobtained from eerebrin,by heating with dilute acids. Gelactose crystallizes in needles,and is someWhat less solUb16 than dextrose in water. Its solution is dextrogyrate and snows b1rotation.It ferments with yeast,but is acted on very slowly.Its osazone is slightlY soluble in water,easilY soluble in hot aleohol and melts at 193 C. Asolution of galaotose 1n glacial acetic acid is optically inactive.On oxidation it yields galactonic and then mucic acid.5sIl grams of galactose reduce 1000 cc. Fehlings solution. ARIBINOSF.,with XYLOSE,is formed and found in a large number of plants,and is of omportanee in building up other constituentse The herbivora absorb and utilize the pentoses as food.In men some pentose seems to be absorbed and used.'l'heypass redily into the uTine,seldom however, in SUfficient quantity to interfere with reauction tests for dextrose.Pentoses have been found in the uriny or persons addicted to the use of morphine. Ar" . 1b~nose 1S an aldose,crystalline sweet soluble in waterqthe solut· . , , ~on 1s dextrogyrate,sp.rotation I04.ti It forms an osazone m~lting at 157-158 C.,does not ferment with yeast,and on warming W~th hydrochloric acid containing phloroglucin forms a red solut10n.4.3 grams of aribinose reduce 1000 ~e.Fehlings solution. • Xylose resembles aribinose in all of its properties,excert in sp. rotation,whieh. is only 18.:l,the melting point of the osazone,I59160 ~. ;and in reducing power.4.4 4 grams of xylose reduce 1000cc. Fehlings solution. DISACOHAR ID~~S 'fhe important d Ls ac cbar Ldes , are cane sugar and milk sugar occuring ready formed in nature,and maltose and asomaltose,produced by the hydrolytic cleava~G of more complex cerbohydrates"Maltose has been obtained from dextrose by the action of the enzyme maltaae,the process being one of building upa complicated ~arbohydrate from a monosaccharide;called reversion. The disaccharides on hydrolysis Yield two molecules of hexoses, they are therefore looked on as anhydrides derived from two mono'saccharides with the re~oval of ine molecule of water.~he dlsaccharides are divided into two groups;those Which do reduce oxid~s of metals.~and t r.ose which do not. CANE SUGAR or daccharose,occurs in the stalk of sugar cane,in the root of the suga~ beet,the trunk of the maple,and in other plants. it is easily crystallized, and very soluble in water,Its solution is dextrorotatorY,with a specific rotation of 66.5 On hydrolysis cane sugar yields dextrose and levulose. CIZHZZOII r H20 -;:. OHZOH (CHOH) 4 COR ... CHZOH (CHOH) SCOCHZOH. cane sugar dextrose levulose. The levulose turns the plane of polarization more to the left,than the dextrose does to the ri~ht,and the mixture obtained after the cleavage has an opposite rotation to the cane sugar itself.For this reason the mixture is called invert sugar,and the change inversion. The term inversion is used to distinguish the cleavage of a compound sugar into monosaccharides. Cane sugar does not respond to the reduction tests.It is not direotly fermentable with yeast~but is eaSIly so ,atter inversion. Inversio~ can be brought about by an enzyme,invertin,oceuring in the yeast;by boiling with dilute hydrochloric acid;and by the inverting enzyme occuring in the intestinal canal.On oxidation cane sugar yields a variety of products,depending on the oxidiZIng agent,and the intensity of the process.Boiled with concentrated nitric acid,it first splits into dextrose and levulose.wl1ic~ are further changed by prolonging the action,yielding among oth&r products,saccharic and oxalic aGids. MALTCSE,is forMed by the action of diastase of malt,saliva~or pancreatic jUice on starch,~nd also transitorilY,bY the a~tion of SU~Phuric acid on starch.It is crystalline,redily solUble in w~tet SlIghtly in alcohol,insoluble in ether. Its solution is dextrorota tory and shows bi-rotation;sp.rotation 137. It ferments with yeast and reduces metallic oxides like dextrose.7.78 grams of maltose reduce 1000 cc.Fehlings solution.lts osazone malts at 206 C.,and is more soluble than glucosazone. By maltase ~nd other hydrolytic agents,maltose is inverted forming two molecules of dextrose. ISOMALTOSE, is produced with maltose during the hydrolysis of starch.It is easily soluble in water, the solution 1S dextrorotatory,sp.rotation very close tothat of maltose.Jt ~ives the ordinary reduction testsli~ not fermentable,and forms an osazone melting between 140 .. :53 C.,soluble in hot water,and hot absolute alcohol tsomaltose has heen produced hydrochloric bY the reversion of ~lucose by fuming acid. Lactos6;milk sugar~ occurs in the milk,and is occasionally found in urine ~uring pregnancY,and after the ingestion of R large quantity of this sugar.lt is arystallizable,faintlY sweet,hatder and less swoet aDd less soluble than cane sugar.tts solution is dext~orotatory,sp.rotation 52.5 Lactose is not fermentable with yeast,but is easily made to undergo lactic qcid fermentation.It peduces metallic oxides,and forms an osazone melting near 200 O.On hydrolysis it yields ~lucose and galaetose.Laetose differs from cane sugar in reducing metallic oxides,and from dextrose and maltose bY not fermenting with yeast and bY yielding mucic acid on oxidation with nitric acid. POLYSACCHARIDES. 'l'hisgroup includes a number of complex carbohydrates, occur in~ in all vegetable mat t er ,'l'heyare all amorphous and e rr r er from the members of the other groups in haveing no sweet taste.Some are solUble in water others swellup in water,and some are apparently unchanged by it,Repeated hydrolysis converts them for the most part into monosacahBrides. ~he polysaocharides a~e ordinarily divided into the;starches, gums and celluloses. SrI'AROHES. THE starches include starch,inulin and glycogen. They are SUbstances of the cornposition9(Ctflo05)x' STARCH,amYlum~occurs ext~nsivelY in plants,especiallY in the seeds,roots and trunk, where it is stored as the reserve food.It is a white~odorless and tasteless substance,consisting of smallgrains Which vary in size and shzpe in different plants.These grains prObably eonsist of two different sUbstanees,granulose and cellUlose~of wtlioh tho first only goes into solution on treatment with di~~tat_ic enzymes. _ Starch is insoluble in cold water,alcohol BDd ether.On heating with water,the starch grains sW~ll up and burst,forming a pasts.On boiling the paste ,soluble s t a r cn {AMYI,ODEX'fRINOF AMIDUI,IN),is formed.So uble st~roh is also formed e.s an interm~diate step or the conversion or starch into suger,bY ~nzyrnes or dilute a"ids. Starch does not reduoe metallic oXides,nor ferment wi~h yeast. With iodine it gives a charaoteristic blue aolor.On hydrolysis, starch is converted into ~lucose,several interme~iate com~ounds being formed. TNULIN,is soluble in warm w'ater wa t nout forming a pastG.'J'he sOQltion is laevogyrate,snd is colored red or yellow with Iodine. It forms Levu l os e on boiling with dilute s u Ipn ur Lc s;Jld.DiastHtic enzymes have very slight effect on inUlin. Glycogen,stands Intermediate between the starches and Jextrlns. It WIll be ~onsidered in connectIon with the l~ver~ GUtd~ • 'Ihe gums are dextrins. 'fhe vegetable divided mucila~es into are the vegitable un ampcr t arrt muc i Lag ea and t n e in [Jhysiological eh erm s e rs t r y , DI"X'I'RINSare o108ely rala ted to the s t ar ene s ,b;~ lng 'formed dur Ing 1heir diges t ionR.nd ;liel din~h 1 ike them. dext rose on comp1at e h y drol~ 8 is. 'I'he muoilages ;:field not only dextrose but var t o us o t ne r hex oseS,and an abundance Qf pentoses.AlcQhol pre~ipltates the dextrins and mueilages.Rasi~ lead acetate p r e c rp i t at ea the muoa Lag es but not the daxtrins. DgX')'RIN (Rritish Gum ),is p r o.duce d by heating starch to ;dOOor 210 C. ,or after moistening 'f"ith nitric 8did to 100-110 G. ,also by boil ing starch with dt.lute acid, and by the act ion of eriz ymes on stercsh.Tn thp.se processes,several steps have been noticed.Soluble starch is first ~roduced,~lving a blue color with iOJ±ne;from this a sugar.and ERY'I'HRODEX1'RIN (colored red with a o d i ne I are 8~lit by hYdrolysis.Srythrodextrin is furthor spllt,formingACHROODEX~HIN (not colored by iodu~e),m-rtltodextrin,and maLt-os e s Pr-om aohr oouex trin,more malto-dextrin,and maltose is split,and finally the hYdrolysis r es m t s in the formation of dextrcse,i'lith SOUle malto-dextrin,whioh rafuses to split further. Commercial'dextrin is a mixt~e of these ~arious dextrins ~ith some sugar. The dextrins are sG1uble in water,the solution is dnxtr06yrate. Whether dextrins reduce Fehlin~s solution .when pure is 38 yet undecided; the commercial er t icl e does, and it 1S iirobable t riat pur e dextrins are reducing agents.'J'hey ar u not iHrectly re r men t ab Le. Gf!:LIJULOSES. CellUlose forms the en i e r cons t r t uen t of the wal t s of p l.an t cells, \"{hile" t h ey are young. In the older cells the ce l l u l os e 1S lncrusted ~lth lignin. Cellulose is enar-aet er ized by its insolubi Ii t y.Ammoniac!:!.l solution of eupric oxide {Schweitzers rea~ent),is the only speclfic solvent for cellulose. 8y the action of concentrated sulphuric·acid,cellulose is aonyerted into YLOID,a substance givin~ a blue color with iodine.On bQiling with dilute acids amyloid yields a monosaccharide. Strong nitric acid conyerts cellulose into nito-celluloses,nhi4h are yery explosiye. HEMMICF.LLULOS~,differs from cellulose in dissolving on coiling with dil~te mineral aClds,with a splitting of the molecule forming monosaccharides. In the hum~an intestinal tract,celluloses undergo partial decom position, forming soluble products whose nature is not definitelY known. ~:NZYM.ES • Hydrolytic cleavage,as has been shown,can be brought about outside the body;bY heat,with or without the aut ion of acids or alkalies,and by the action of certain sUbstances called ferments. In the body~wher.e these cleavages ere so important,the high temperature or the chemical reagents necessary for the splitting,would cause immediate death;consequentlY in animals,the change must be brought about by the ferments. Ferments are substances that de~ompose others,\vithout being ohanged themselves or permanentlY ut il ized. 'rhe act lV 1t Y of all ferments is impeded by the accumilation of the products of the fermentation. their activity is oontrolled by the temperature,and character of the solution in whi~h they act.Every ferment has a certain temperature at which it is most active,the optimum temperature. A higher temperature first impairs end than destroys its actiVity. All ferments are permanentlY destroyed by heating to 100 C.with water.Coo11ng impairs their actiyitY,but eyen after freezing they regain their power,when carefully brought to the proper temperature.Some act best in acid,others in alkaline,and t others in neutral solution of certain concentration for eacn ferment. During activitY,some ferments galn in power,while oth~rs nelther gain nor loose,. ORGANIZF.D F~:RMEN'rS,make up the first class-.'fheyare .1iYin~ . unicellular organisms. Fermentation resulting from theIr actIvlty is closely related to the life of the cell,and the formation of new cells. Salicylic,boric and arsenous acids,chloroform,and thymol,phenol and all disinfectants,will in certain concentratIon kill these bodies. ENZYMES or unorganized ferments,constitute the seeond group. They are sUbstances resulting from the a~tivity of special eells. generally of the hi~her animals.1t is probable that the a~tivity of organized ferments is due to their secreting an enzyme;and that the increase 0 ower observe in organized ferments during aotiv ity,is due to the increased amount of enzyme secreted by the constantly increasing number of cells~nzymic action is not noticeably impaired by disinfectants.This diYference is probably d~e to a killing or crippling of the cells of the organized ferments,praventin~ a $6cretion of enzyme. The chemical composition of the enzymes is not knownj As yet no enzyme has been prepa.red in the pure s t a t ev'rnev may be extracted from the cells by means of water ~nd glycerin.The solution in glycerin is very stable. When in solution they are easily Obtained by precipitationof some other sUbstance from the same solutioR;the enzyme being ca.rried down with the preoipitate.The activity of their solution is usually destroyed by heating to eO C. EnzymIC action is catalytic,and is a physical action, resemb lang the act ion of so Lut ions of colloid metals. '1'heanalogy is shown by a solution of a colloid metal,causlng the liberation of oxygen from hydrogen di-oxide,the inversIon of cane sugar,the decomposition of calcium formate with liberation of hydro~en and the formation 'of calcium carbonate and carbon di-oxide;anJ by the loss of activity on boilingCatalytio action has been explained on the hypothesis th3t oxygen is capable of eXisting in both the bivalent and tetravalent state;ohangin~ from the tetravalent to the bivalent in the presence of the catalytic agent. The important enzymes are classed as.AMYLOLYTIC or diastatio, PRO'fEOlIYTI C, S'l'F.A1'OL Y'I'YO or fat spl itt tng, INVI:t~R'rlNG, an d COMlULA'l' INn. They are found in the human body In the dIgestive Juioss,and In the blood.The glucoside and urea splitting enz~rnes are found tn plants. DIGF.SrflON. The pro~Ass 0 igestion is both me~han1~al and chemi~al.~he meehanlcal action causes the disintegration of the food materials, preparin~ t~em for the ~hemicBl action of the dlgestivs agents; further the food mass is mechanically propeled along the entire length of the digestive tra-ct,being brought i.n t o successive contBct with the various digestive secretions. Some nutritive sUbstances are soluble in water,and pass dIrectly into the s~:{stem;but the greater part of food material r3quires o a chemical change,usuallY an hydrolysis,before bAing ubsorbed This cleavage is brought abuut bY the fluids secreted oy the :? digestive glands. 'I'hestudy of the process of digestion,begins witt) the stUdy of the chemical composition and Bction of the digestive flULds. Although the fluids are ~istinct in their aelioh and oomposition, and the expressions oral,gastrie and intestinal digestion are used to con~enientlY designate the Chief alterations of the foods in these portions of the tract;it must be remembered that these changes are interdependant ,and 18ny disturbance of one process,will effect the rest. ORAL D1Gj<~srl'T0N I SALIVA AND SAL1VAPY DIGRSTION. 1n the ~outh the coarser portions of the food are ground and torn by the teeth,an4 with the softer materi al,thoroughlY disinta grated and m~xed with the saliva. SALIVA is the mixed secretions of the ~arotid,submaxillary,sublingual and buccal ~lands,in men.Tt is albumInous and mucous in its nature. Saliva is a watery solution of abuut 5 percent of SOllds.Tna important solids are ptyalln,an amylolytic enzyme,proteid,mu~in and saLt s v't'h e saLts are alkaline and earthy phosphates,ca,rbonates and chlorides;and potkssium sUlphocyaniJe.Saliva is normally alkaline in reaction,but may be neutral or aeid.Pathologically saliva may contain sugar,in diabetes;melanin in Addisons dosease;or bile pigment in i.;terus.Leucine and urea have been found in saliva an uraemia. The amount and the quality of saliva secreted,is governed bY certain nerve influences.Stimulation of the glosso-phar~n~eal nerve,produces a watery secretion from the parptid gland,containig lng litlle proteid,diastatic enzyme or salts. Irritation of the sYmpathetic inhibits secretion;but stimulation of both nerves, Causes an abundant floW of parotid saliva,which'contains much ~anic matter but little salts. The sUbmaxillary gland,on stimulation of the chorda tympani7will produce an incr.asedamount of salivB,called chorda saliva;whioh is poorer in soc1lidconstituents,than the vis~id,s?mpathetic saliva produced by the gland on stimUlation of the sympathetic. Section of both nerves ives rise to a thin watery secretiun-the paralytic saliva. ihe alkalinity of the saliva aids its diastatic function,but is more illportant beeaus e of the... s t rrnulating effect or the weak bas t e solution on the floW of gastric Juice.Acidity of the saliva haa been observed in many diseases and even in health,so that its diagnostic significance is not grea t st'h e formation of lactic acid by termentation in the mouth;is a common cause of a~id saliva. The quan tity of sal iva secret ed in a day is about 100 c <J. The floW is easily excited by reflex stimulation;as by the smell or sight of food;or bY chewing of some insoluble sUbstance. Tn salivation t her e 1S a great rnc eeas e of the r t ow of s aLi va an d thp. resulting emaciation,is probably due to the draIn of water from the system ~nrl the dilution anti neu t ra Lt za t i on of the f~astric Juice,bY' the alkaline fluui.Diminution occurs but se Luom. an d IS always assocIated with ~eneral rlisturbance of secretion. Prya Lan t he d i a s t at t e en zyme occurs in t rie saliva of all an una.Ls except the pure carnivora. 1t is characterized by its action In eonv er t i r»: starch into sugar s Th e enzyme acts best 8 t 40 C. ;in a neutral "~solution,although it is very actIve in a weak alkaline soLu t i on and is active in acid solution up to .2 percent un ner-a I acidistronger acid stops Its action,but doe~ not kill thH enzym3 unless the ae i d be concen t ra t edvr ne en zyrne t her e r or-a retains its activity in the stomach,as long as tne gastric Juice does not exceed this acidity_ The activity of ptyalin,varies w i t r, different s t a.rch es a ccor d ang to. the amount of cellulose they contain an d also Whether theb are bOlleJotraw.lLs activIty is Im~aired by teaJon account of the tannin it containstless so by coffee and ~oca,lts actIvity, also is modified by such drugs as atropine,which inhibit secretion 'rhe activity rs increased by common s a.Lt hor se ra{jish,~inger,rnustard &~.and by SUbstances stimUlating the secretory nerves.The ptyalin occurs in greatest proportlon in the first portion of saliva seereted,beooming less ~n each successive portion as saliva ti on is prolonged.Amixed saliva of half an hours s ecr e t Lon under stimulation,will contain an average proportion of ptyalin ,and is . always used for- the estimation of this enzyme'S a ct Lv i t y , As it is not possible to colleet and weigh the ptyalin,its quantity in saliva is measured by its activitY,bY means of the method of daae t aaLme t r y , (See rea e t aons of saliva.) Salts, Theso consist chiefly of alkaline chlorides,mixeJ with earthy phosphates,and calcium bi-carbonate.Sulphocyanate of potassium is a variable oonstituent. Yuein of saliva is a true glycoproteid,and is easily isolated from saliva and recognized. Glucase,is a second enzyme occuring in saliva,it converts maltose into dextrosei i i j c j 'fhe i ('11<t~s 8:nd some other S81i~ary ~lands.1his ~ower ab8or~tiQn. dl·ugs.arahs.bit1l811y IS used in rleasurin~ secreted OJ the the rapIdity of (l. neral P98Jt ions of rni xe d Saliva ..' St.imuIBte the r OIV of sa1i'la b'y p18cin~ in tl"l":t mouth ~. Sl'lall"Jlass rod rounded at both ends. Gclll"~t r n a sui t a e l e vessel a.n d f 11 t.e r , a. 'fest t rie reaction 'of fresh salivai .... ilh s ens i t rv e I r r.nus :,d:lper. b. Allow Observed a rew oe.of sa11va due to to the preo1pitation stand of 8 Jay ur two -n ~louJlness ~alcium oarbonate. ft1d acetic acid to a few ee.of s81i'l~-a praoipitate idsoluble in an exce~s of rh~ acid- Muoin~ d. ld IS formed, d. ~o a fp,w co.of saliva add nitric acid - a preoi~itate is rorme~ soluble on heating with R yello~ Qolor;u~on the ad~ition of an excess of allr.al i the color enang e s to oran~~e.o;anthojJr~t ~10 r":;I=i<;. e. Add Mill-ana raaMsnt to a t e« O~ .. or saliva and t;o,il,,-el trier pr e e ap r r a t ed proteid e r t ne soll.~tion t ur-ns rad. f. or 1£1 t h€ A... td eaus t ac p ot aan to a small port ron of saliva an d t r. en a Jrop. t wo of dilute oopper SUlphate solution -8 blutst'! Violet '~olor fJroduceJ eSf)eciallY on4~~rmin5. Biuret rea c t ron , he~ognit ion of Potassium sul{jho-::yar.1.de f' Y,t;NS ~,i,. the saliva·-:ro a '1e. no. o~ the sall~a a~J one drop ~f ~Ji",arg~c.J.~~ a"ld end 6.. f &w... ,lrops of v er Y t.lll ut t~ ~err 1c chlor Ide sol ut 10n •.~ red co Lor a t lor i]Ue to the ror-ma t acn of iron s u lp noe yen Lde as p r o du c e dEeco~nltion of Vt100n in the Sali,.va.-lnto-,:lOOcc.of ;"bsalute a Lco n-al ~our 20 - 30 ceo of 8811'18 tnot filtered) and Shake th~rQUHhlY. Place in an ~rlenm~er flask,lay thQ flask on its diJe.ana alloW i,"1'~ p r e e t p t t et e t o subslde.Pour orf the flnld and n1f»~at the operation ~ tlmes;than filter.cQllA~ting the preCIpitate ~n a sr~ll filter,wash with absolute aleohol,then with ettt~r 804 ~laGe In a dessieator for ~ hours. 1. 'I'he c1ry Sllustance is insoluble 1n water. Upon t~e c.t1dition of one dr op of ~8US t i IS sode .• it passes ,Jradually into sol u t ion. 'fhis Solution ~ive8 with a trace of ~o~per sulphate th& biurot re~dtim 2. Roil the remaind(~r of the dry m\l...:in for 8 rew minutes with a small quantity or dilute hydro~hloric 8oid;allo\Q to cool ar}\.t make a~kaline with caustic soda. Add a few drops of mixed PehlinJs solution and boil.~~ithe'}r a yellow or a red fire~ipi tate is produc:"d. a. Praparation of starch past~o~Powder finely one grem of i~areh in a mortar and add 10 cecof water rUbbing with the pestle until a homogeneous mixture is obtained~Pour lnto a beaker containing '90 ,ceo of boiling water.and stir until a smooth paste is formed. On a clean wh1te surface (a ~orcelain ~late) arrange a s~ries of drops 0 dilute iodine solution.Brlng the starch paste to a temperatur of 40 O. Place Bxactly 10 ~e.of the paste 1n a te.t t~be and add to it one ac.oe saliva shaking thoroughly.KEEP the mixture, at 40 C.and at the end of one minute remove a drop Oflt ,and add to the first drop of the iodine series;repeat this every minute until the color of the mixed drops is extinguished,indicating the conversion of all star~h into simpler sugars.With normal ~aliva the color w111 disappear in six minutes. Recognition of the products of salivary digestiono '(0 TO cc.of starch paste add one ce.of saliva,and digest at ~O elafer5t~eRtpfmthetd~gested mixture in a test tUbe and add a small quantity of Pehlings solution,on boiling the oopper is reduced.Repeat the experiment with boiled salivao b. Pill a fermentation tube with the digested material and add a small piece of yeast;allow to stand in R warm olqce for 12 hours. Influence of ~oids and alkalies on salivary digestion. Into eaoh of four test tUbes a,b,o,and d,place 10 cc~ of starch solution.To a add one cc.of a 0.25 percent solution of hydrochloric acid,to b one cc.of 0.5 per~ent acetic acid solution,anJ to o,one co.or a 0.5 percent solution or sodium carbonate.Add one cc.of saliva to each of the four tubes and shake thoroughly.Arrange on a por~elain surface four rows of iodine drops lettering the rows to correspond to the test tUbe~ .. Place the test tUbes in a water bath and heat to 40 C;At the end of one minute withdraw a drop from each tUbe by means of a cllass rod, bringing the drop in contact with the first drop of iodine in its corresponding row;repeat this process every minute as directed under diastasimetry ;for 8 minutes. GASTRIC DTGEsrION. - 'rhe food,after trituration and miXing with saliva,lon the mout n, passes through the oesophagus into th e stomach. Here the food mass is SUbjected to a kneading process and is acted on by the gastric jUice,which with the assistanoe of the swallowed fluids,reduces the mass to a liquid state.Part of the food is now absorbed through the stomach wa.ll,but most of it passes on through the pylorus into the duodenum as ehyme. Our present knOWledge of the composition and'mode of secretion o~ gastric jUioe is due in great measure to the use of gastrie flstulae;made on animals and occuring accidentally in men. Th~ aeeretion or the gastric jUiee is not continuous,and ia brought about by ch6m1eal irritation or the gastric mucuous memb~ane or by paychic influence. A passionate desire for food,~111 e~us~ a flow or th~ jUine,but always after a pause of about rour minut~s.Chemical irritation of the gastrio mucosa,as by the ak alkaline IDeas of food and saIiTa,causes a slower but mora continuous 110w.~he pr~senee of free acid in gastric JUioe cannot be demen!trate4,until about 20 minutes after the - - swallowing or food.'!his is uue to the power of pr o t e ads to form neutral compound ~ith r.ydro~hloric acid.Durin~ this time the ptyalin of sali98 is aotive in the hydrolysis of starch. There is a ~onstant formation of lactic a~id during this early stage of gastric digestion,Which however c8asea,when the hydrochloric a~id acid reaches .07 percent ~hf quant1ty of jUi~e secreted durin~ digestion varies With the quantity and quality of the food.'l"hlS action of various foods,meat bread and milk 1S arranf$ed in tJro~ressi'le series as folloi'8 , .bY Hammerstein. A.eidity Digestive Acti"ity Duration of activity. Meat SF fi:AD Bread Milk ~eat keat .• B~ead Milk MILk. Composition of Gastric JU1ce. 'I'ht~astr 1c. Jui"e, can hardly be Qbtained pure and free from foo4 residues,or from mucuous and saliva.In man it ia a nearly oolor1esa fluid or an acsid taste and a distinct acid reaction. "'he aoid re•• t1on dependa on the presenc~ or free aCId, chiefly hydrochlorio.Yhe quantity or hydrochlo~i. 80i4 in normal JUice is from .02 to .03 pe~oent.Arter partaking or food,pat1cularly aftor a meal "rich 1n carbohydrates,lactio aoid oocurs abund~ntly,an4 sometimes acetic and butyric aoids."he persiatant occurenceor lactic acid with a diminution or abscence of hydrochloric acid in the ~aatric JUioe is indicative of dancer of the stoma~h. Perfectly fresh ~astric Juice Gontains a little nucleoproteid and on standing for some time contains albuDMises. "he remainder of the organio matter consists of a small amount of mucin and two enzymes.pepsin and rennin.'j'he inorganic material is a mixture of the ohlorides or sodium,calcium,potassium and ammonium;Wlth the earthy and iron phosphates. 'lhe free hydrochloric acid and the pepsin and rennin,are the physiologically important constituents of the ~astric JuiGe. Pepsin is ~haracterized-bY its action on proteids.lt is active Only in acid soIUtion;rormin~ peptones • .tn the conversion or slm~le proteids into peptones,by gastric JUlce;ACID ALBUMINA~·F. is first formed.The acid albuminate is split forming compounds poorer in carbon. called primary proteoseS.'l'hese aTe or two kinds,one solUble in water,called PRO~O-PRO~EOSE;th. other insolUble in water,but solUble in dilute salt s'lutions, called H~T~RO-PROTEOSg.The proteoses differ,according to the protein from which they are derived.Proteoses from ~elatirie.are g eLat ca es rrom fibrin fibrinoses,from'albumip eIbumos ea ~diiBy further sot ion, T hft!l!e pri"'1F!.ry prot eos es form dent er6-prutao,S.(j., -. '. DEUTERO-PROTEOSE is finally split forming P~P~ON~. . .~ The prote,oses are precipitated When their solution is saturated with ammonium suj.pha t e l p ep t onas ar e not .Primary pro t eo sea ~re preoipitated from neutral solutions by saturating with sodIum ehlor1de~deutero-proteoses are not preoipitated from neutral 801ution,bllt are,after the solution !las been acidified by aceti~ acid.Copper sUlphate aomplet~lY preaipit8tes the primary proteoses,but does not erfeet deutero-proteose.Peptone is the end produ¢t of gastrio digestion,is diffusible;and is not chancled by the further aetion of pepsin. ~he change of proteids into peptone is a pro~ressive reaotion, all the intermediate products eXist at the same time in a ~astrio digestion;their relative quantity depending on the time the process has progressed. A complete change of all 'the proteid into pe~tone,is prevented by the accumilation of th~ products of peptic activity. Compound proteids are split by gastric JUice,after Which the digestion of the simple proteid portion proceeds as above.Th~ nucleoproteids yield a peptone free from phosphorous;tn6 nuclein split off being unchanged. The AalbuminoiJs,are characterized by not yielding ~ny hetero-proteose,showing an absence of this sidechain of the proteid molBcule.Co~lagen is first changed ihto gelatine Which then forms sucoessively an acid albumin,protoproteose,deuteroproteose and gelatine peptone,Elastinis not changed bond the formation of protoprot60s~.Keratin. are not decomposed by Igastric juice • j . Rennin is a milk curdling enzyme.lt is present! phJ.iolo~icallY in all human gastric Juice.Pathologically It is absent in oarein oma ,atrophy anc ohronic oatai-rhof the slomach.ThelJresenoe or rennin in gaatri. JUice is shown by its aotion on milk. (See the direotions for the examination of milk.) Hydrochloric acid of gastric JUice is all derived from the sodium chloride of the food,bY the pO~6r of selective absorption po •••• ed by the oells ,of the ~8strio muoosa.The oell. split the aQdium ahlor1de,by hydrolysis,sending the alkali in,to the blood and the a.id into the lumen of the gland. 'l'h~chief runction of the hydrochloric aoid 18 to aid the enztm1c action ;as a d1sinfectant it has sli~ht power in,,~o weak a solution. The quantity of a~id in the gas trio Juice is constantly lowar than normal in diseases Where the gastric mucosa is affected with catarrhal inflamation,cirrhesis,or fatty or amaloid degeneration. It 1s usually diminished in anaemia and neurasthenia.In carcinoma it is frequently entirelY absent. An exoessive secretion of hydrochloric acid oocurs in ulcer or the stomaoh .An inorease of the acidity is present ~n cases of hyperaciditY,depend3nt on direct irritation of the mucuous membrane by the food;~orupon abnormal secretion ,the result of "disease of the nervous system. EXAMINA1'ION OF GASTRIC JUICE. Clinically the examination of 'gastric Ju~ce is an important aid to diagnosis in diseases of tho stomaeh.The activity of this secretion depending to a great extent on the quantity and quality of the food;it is necessary in order to obtain results' capable of comparison,to administer to thB empty stomach a mebll'lhose composition is constant ,and to evacuate the stomach at a definite interval from the ingestion.For this purpose several test meala are recommended of which [~\\7alds,given below~is the roost convenient as digestion if! at its height at the f)l},j of an ho ur an.d the s t omaen contents are then comparitively clean and easily removed. Rwalds test breakfast,consists of 70 grams of white bread and 300 cCQof weak tea.~he stomach is emptied after the lapse of an ~our. j 'l'he digested rnat er t a j is removed from the stomach by means of a soft rUbber tUbe;and the miwture is filtered and tested by means of the following reagents. Recognition free hydrochloric acid. In the absence of a SUfficient supply of gastric jUice,prepare the following solutions. or P.- Dilute one c c s o f hydroshloric acid with 89 c c s o r water.'l'his solution contains about .25 percent of acid. B.- Dilute 10 cd.of A with 40 CC.of water. c. Dossolve 0.8 grams or lactic acid in ICO c~~of water. D.- Dissolve 2 grams of e l bumos e in 100 c e s o r watf31"'cl"ilter .. Reactions of these solutions towards the following reagents. 1. 'l'ropaeolin. 0.0. au To a few cc.or A. add a few drops of the tropaeolin Solution.Cherry red colorQRepeat the experiment with solution Do b.-Dilute a portion of A with equal volumes of water and of D;add a few drops or tropaeolin solu~ion and compare with the colors previouslY obtair.ed. !5 c. ~o about ce~of C ad~ a few d~ops of tropae~li~ solution,and dl v i de the mi x t ur e in to t riree n ear 1 y equal par t s •1-.2 all <: 30 'fo lade! an equal volume of water!to 2 an equal volume sodium Chloride solution{3 percent) ;to 3 an equal volume of e on c en t r at au sodium ~hlor1do solution_The solutiona 1 and 2 are not ehanged,3 changes Its oolor to rose~ oi d. -Bring a few drops of eaoh of the solutions A,e, and D into a porcelain dish add a few drops of tropaeolin solution and evanorate over the water bath to dryness (avoid strong heating)oAn . intense blue color of the residue is obtained. Albumose in small quantity does not interfere with this reaction. 2. G{Jl\jZBURG~) REAGEN'!'. To a few drops of solution A in a porcelaih d~shadd a !e~ dro drops of' tIle re ag en t and evapor at e over the wat ar bath (a,void e xeen sive h6~tingJ-purple red rasidueo bo Repeat t~e experiment with Band C separate]y;also with'a mixt ur e of' j:'; end Do Albumose does not Lnt er rere w i t h ""1"" ,:,,,,.~,,,,'·7~~ .!._~ un:Lcss f)1'8Sen"t in great excess;laetia acid does Dot give the test Ba • Repeat the tests Dade mi x t ur c ~Ls ::1GI" est .~ ..." _ \0 reagent. under Gunzburgs less e xp enrsLv e G,bl e ana _ th2TI Iw J \i,r 'i'h e .......,,:: ...'\.,; >_ ..... J r es cr c rn Gunzbur~s.enJ ~ , is said to be equally se~si[iveo Prepare ferri.c UCfelmsns ~3111-o1"i,de to reagent by the addition of a few drops of 10 e e s o r a 2 percent solution of oarboli0 amid a~ To a few c~Gof solution A add a few drops of Uffelmans reagent~ decoI or:t za t :f~0'1-1c b. Repeat experiment a;but use solution C -lemon yellow colo:o Co Mix equal volumes of A and C and add a few drops of tIle reagent . ~on ye.now color"Hyal'ochlorie acid in this strength d oe s 'Jot . p r-even t ecogn i.t i.on lactic d4 To about 15 cc&of C add Uffelmans reagent and divide the solution into three portions (I) (2) and (~).To (I) add an equal volume of w~terlto (2) an equal volume of 3 perGent sodium 0hlorida solution?to (3) an equal volume of sa t ur-at ad sodium ehler-ide' the r of acid" soluti0n;-(3) is dacolorizedo In general the presence chloride doss not interfere with the reaction. of sodium e a Mt~ 26 ee , of A'i of C~.and of D an d. shake thon:HJ.gh].y xn a separ-: ating f~nD91 with an equal vol~me of 6th8r~S0?Brato ~J~0 sth0rial extrac~:( i:1,::1Jt n.:tt8r t hr ough f" dr y filter<7A:U.ow the ()th,~;l~ t o 0'1'8.[<" orate vdissolve the residue in a little water and to ~ p~rtioD add Ufre':"L~r.\3!lS ",r·0Fc1:-2"6I.lt;:.ltl-l.is me t ho d is u-sed \~"henG" ..r e r t11D SO.LU~1.011 ~Jr lactio B0id is colorod,Bs in the DBse of stomach contents;it also -': s ep ar f:"", at ('Ii:; J.clGt:i.e ReGogGitioD clf The pras0Dca 8,C iii r r-om ;0; ubs t an o o s which g:t VEl a ~ imi18.l' co Lo r , PEPSINg of pepsin in a solution is shown by the POW6? of the :30~t.l.lti0i.1 to dj.t'Sost albumino'l'he quantity of p ap s Ln p:'osent measured ''0y th e amount of c.oaguj a.ted albumin di.ges t e d b:l"the j,s 801u''~ . tierl in a definite time Frepare h solution of 005 grams of pepsin in 500 co-of a a25 percent solutioil of hydrochloric aeid" When estimating the proteolytic aotivity of gastric JUice~add ·t~ 25 0coof jUiC0 enough hydrochloric aoid to make the ad.dity about 0,,02 percent. In Gach of fivG test tUbes place 6ne gram of fibrinoTo test t ub e CA) add one c c -c r gastric juice or the pepsin hy dr oc h Lor' ic acid sclutioD.~o tube (n) ad~ two cc~of the di~astive rluid~TO I: .. (C) add 3 cc. to (D) add 4 cc. and to (E) 5 cc.-Plaee the tUbes in a water bath at 40 G. for an no ur s At the end of r n rs time the change In~tha bulk of the proteid in each tUbe will give an idea the quantity of pepsin present.With normal gastric JUice,sll the fIbrin in tUbes (D) and (E) ,will be dissolved. or Estimation or the quantity of hydrochlori~ aaid. rhe aeictity of gastric Juice as manifested by lts react~on wlth litmus or phenol-phthalein,lS dUG nut only to free ~dld ,but alsQ to acid salts. A quantitative estlmation of the acidity of ~astrlc ..1uiee,wii.hout·reiSard to its source is termed trie estimation of total acidity and 18 usually expressed as hydrOChlorIc acid. The estimation. To TO c o o f t he filtere(' gastric JUice ad d a few drops of phenol-phthalein,place the im x t ur e in :3 beaker and a dd about :65c\}. of distille.! water.From a burette add slowlY,dith constant agitat ton deai-normal solution of sodium or potassium h.vdroxid(~,u!'til the liqUid in the beaker hRS a sli~ht reddlsh color,whiah does not disappear on stirring. Ft'rom the number of c e s o f a Lke.Li used ca Leu Lat e the quantity of v a e i d pr e s e n t , Congo red is not ch arig e d by 20111 salts or organic acids,a titration made .with this sUbstanoe as an indicator will show the amount of FREr~ HYDROCHLORtC ACTD. . r Artificial I. Preparatl.Qn a"~le , I pepsin Gastri~ Ji6Bstion. digestive solution- Tlisti()l~ei grams in a litre of 0.4 percent hydTochloric acid. of the 2. lilatar tal for .ti~ as t ion. A. ~resh bloo~ fibrin or coe~ulated fibrin ~r6served of in chloroform \'Ister. B. 'I'ne meat residue from the preparation or er ea t an e f~c. (see muscle) c. 1'he Whi t e s of Ti:) eggs t nat ha.e been c:oagulated by boiling, and then finely divide~. ~T~h matertal may be a4~e4 d.1rectly to the ji~estive sol~tion,but ·(Joe.gola,-edmaterial shaUl d ne treated as follows ,before adJi t ion. Plaoe the co aguj a t ed materi.al In a saucepan,s<M one liter of ~ater and one ee , of h'ydro~hlorie acid; and heat ov er the 1ft!ter bath until the material gelatlniz6s..... 1Io. tCl 0001. Bring the p r o tea d Into the nottle c:onta1oiog the digest ive fluid and place in the th~rmostet at 40 C. for ten daysAt the ent of this time filter t ne dif5eaniye pro4ucts r rr st through linen, t hen thro~h a la.rge folded filter. Pla..:e the fil trate in a saucepan and Narming to 50 c. o.er the water bath neutralize with sodium earbonate.T( 8 precipitate 1. formed,filter and evaporate the filtrate first o.,er a free flame,later over th& • w~ter bath,to about 800 COe If ~n th~ course of e~aporation a co~gulum is thrown out,filter before the solution becomes too oin~ ~entrated.Tt is necessary during the Avaporation to kaep the solution neutral.The evaporated residue is a solution in water and s o-t tum .-;hlo'"'iri0. of the ~lbumose an d peptone. Separation of Albumose::.and Peptones by weans of ammonium sulphate TOO grams of finely pow-rer ed ammonium sulphate in a' pour upon it the solution of a Lbumoa es and p ep t one j anu r ue with a pe~tle in order to obtain a saturated solution_ The albLmoses are precipitated at first as a sticky scum,which b) stirring may be brought together into a v~saous mass \~ich adheres to the ~estleeD~cant the solution (to be used in the preparation of peptones ) from the precipitated albumoses;wash the lEtter by decantation with a saturated solution of ammonium suIphats?place in a sauce pan and dissolve ln a little water, Add er-o ugh "water to make the solution measure one liter,boil over a free flame (replacing with hot water that lost by eva~oration) and add powcer-e d oar i um carbonate in sma LL por t aons until ammonia' ceases to be ~iven off:and a filtered portion after ac~difYlng with b y crocn.lor f c acid no longer gives a p recap i.t a t e l"ith barium ch Lo r Lde ..Wpen the ammonium sulphate is completely de comp os ed , filter and add to the filtrate first ammonia and then ammonium oarbonate solution as long as a precipitate is formed;~armtallow to stand a short time and filter.F.vaporate th9 filtrate to a small volume over the water bath (best in a porcelain dish' ),allON to cool and ~recipitate with an excess of 85 percent alcohol.Allow In6 albumoses to remain in ~ontact Nith the alcohol for 2 hours then decant the liquid and bring the albumoses in contact with ' absolute al<?Ohol for half an hour.'rhe a Lbumoe es wn i cn a t first are S?ft and s t acky are hardened by this treatment and may be rUbbed w~th a pestle to & fine powder.Collect on a smooth filter vaah wlt~ ether and press on (lIter paper. \~he albumoses obtained in this manner are a m~xture of prqto- and hetero-albumos~. dysPlaee mor t ar j \ reactions of albumose. Dissolve 5 grams of albumose in 100 ce.of water ~arming~Filter the solution and by gently fA) B . use CQr the rea~tionB. , 011 a fe~ cc~ of the SQlut10n;it remains Efter the addition of aceti~ acid. unChanged even (B) AcidUlate a portion of the solution -ith acetic acid and add ~~ equal Volume of saturated solution of sodi ..' t i on becomes e.Lou dy cLear-a ' 'IV . ~ chlol".l4e.'lhe solaclOUdy again lfheo c~Ol. ng hen heat 1S applJ.e.lf an~ b-e~oming (0) Add a little SOdium Chlorid.e sO'1ut"on to a Ib umos e solution;and then one or ~. two drs ~ a few c~. or the ---- --'-,-' .~_,~ __~ _ -; __ .~. ~ __or n i'tl" t c aci<Ct. Ei ther ~ a cloudiness or a precipitate is produeed;both disappear on th~ a~dition or more acid.The solution on standing or on heating turns yellow;the yelloW eolor changes to orange wh~ caustie alkali is added. (D). A~idulate a portion of the solution with a f~w drops of acetic adid and add potassium ferroayanide solution.A cloudiness iff p rodu ced ,which disappears on n ea t t ng (often not e omp Le t eLy ) , (F). A.dd to a ,Jortion of tne solution half its volume of caustic s~da solution and then one or two drops of a dilute solution of copper sUlphate. (Biuret reaction). ~,\odifi8dBiuret r ea et ron- Ad d to a portion of the dilute solu~ion half its volume of caustic soja s olu t aon s HoLd i.ng the test t uee inclined,pour a dilute solution of oopper sUlphate upon the mixt ure in the test t ub e In such a manner as to a v o ad mixlng.'fhe characterIstic aolor developes At the line of contact. (p). Dilute 5 0C. of the solution with 45 ec.of water.Aad to small portions of the solution,mercuric chloride,tannin.and phosphotun~ stic aeid.ln A8Ch-ease a preci~ltate is formed. (B)~ A~d Millons reagent to a small portion of tha solution and bo11-a red precipitate or a red solution is fo~rned. Preparation ~ of peptones. 'fhs satura.ted solution of ammonium slllphate.whieh was deoanted from tM' pr.ecipi. t a t ed a Ibumca ee ,eont aana peptones ari d a small quantity of deutero-a.lhumo,s~.·rofree from traces of albumoses,ctissolve in this solution by heating 20 g rams .or ammonium sulphate;allow to cool E\Iid f 11 t ar ,B~rore o on t Lnua ng the s epara t i:on "take out a small portion of the fl1trate.and add an excess of strong CBusti~ ~otash solution and a few drops of dilute ~opper solution.If an intdnsely eolored solution results,peptones are present in sufficient quantity to warra.nt t ho t r isolation. free the aoLu t ion from the gr.ater part of the emmon tum su!phate,evaporate over the water bath to a small 71olume,allow to cool end filter or de4ant. Bring the filtrate into ~ sau~e pan,add one liter of water and treat with barium oarbonate~o. exae t Ly as in t n e preparation of a,lbumoses.Peptones prepared in this manner usually eontaln oonsid_arable inorganio salts. Reactions of peptones- "0 Pept~nes respond to all the reaotions excep t on,' C) , (D)• TNtEsTINAL as given un~er a1bumoses DtGF.S~tON. Normally the digestive seeretions of the stomach and those that operate in the small intestine,are maintained in a s t a t e I of physiolo~ical equilibrium, the entrance of the chyme into the dUo~ denum provoking a reflex secretion of the ~ancreatic and b~liary" fluids to an extent sUfficent to ne~tralize the acid contents of the stomach,and to establish the de~ree of alkallnltY,most suitable for the action of the ferments ~hich complete the action or digestion. A moderate increase in the acidity of the ~astric contents is followed by an increasod secretion of baLe and paner e-at t e JU10f}; an rj is iJrobably the eaua e of t ne oecur-ance of hyp er-acaa ity of the gastric jUice 1n certain functional diseases of the liver and p~ncrens,th~ increased acidity bein~ a stirnulus,~rovlded by natur~ to aause B more active secretion. Prom these facts it is seen that the digestion and sUbsequent" absorption of food depends not only upon the integrity of tha liver and pancreas, but also upon the due performance of th& fun~tions of the stomach. The secret ions of the pancreas are t \'/0 in number; t he external or pancreatic jui~e;and an internal secretion ,having glyoolytic . power,lfhich is ,teli'lered .i rree t j v into the bLoo d c whe r-e it changes glycogen into suga.r.'l'.he occur anc e of sugar in the urine in disease Qf the pancreas is probably due to interference with this function 'l'hepancreatic JUice 1S an aLk aI ine fluid con t arnrng sod tum cerbonate in excess of any oth~r salt,and five ferments;trYRsin,a proteolytic ,amylopsln,a diastatic,steapsin,s fat splittin~,an emUlsifying and a milk curdling enzyme. rhe secretion of this juice is intermittent,and its character depends on the kin~ of food ~aken end the sta~eof ,tigestion.'l'he secretion increases rapidly after eating,and rea.ches its maXimum in the course of the first three nour-ss Pr-om this time tht~ secretion diminishes butm..-=.y again in areas e from the 5th. -7t1'lo hour ,when larl'l6 quant ities/of fooa,genp.rally pass from the stomach ~nto the intestine. Prom this time on it gradually decreases until it finally stops at the 15th.-Idth.hour. '}'hequality of the food has ,al1 unmistakeable influence on the composition of the Juice an~ the quantity of tne different enavmes ,'j'h3 jUice is always riches t in diastat io anzyme after a bread ~iet,and riehest in steclpsin after a fat meal. . . AMYLOPSIN,~s closely related to ptyalin,and converts stareh,raw or boiled,into erythrodextrin,achroode~trin,and finally into maltose and dextrose.'}'hedextrose is prObably formed bY the invertin of the intestinal juice. Steapsin,splits neutral fats into fatty acids and glycerin.'tne ratty acids,the alkali and the emUlsifying enzyme act on another portion of the fat and form an emUlsion. TRYPsIN.oonver. s pro ds into peptone in alkaline or neutral solution,acting most energeti~allY in a weak alkaline mixture. The proteid is first con~erted into alkali albuminate,~hich is then changed into deutero-proteose;no primary proteoses being obtained.The deuteroproteose is hydrolizad formin~ peptone,similar to the peptone of gastric di~estion.This peptone (A~PHO-PEPTONE) is split bY the further aetion of trypsin -formlng a pe~tone of lower molecular weight,called AN'n-P£t~P'l'ONF.;and amidO-~,cl.ds. AMIDO AC1DS,rormed aspartic bY triptic acid and tryptophane. 'l'YROSlNand L"~UGlN,are described duets of pancreatic diKestion~ Asparti1 acid is amido-succinic # dl.~estion are tyrosin,leuein, w'ith the reactions acid of thO' produes CZH3NHZ(COOH)2 fryptophan is a chromogen rorm~n~ a viol~t color with bromi~e • The quantity of acids formed from tne proteid 1S about equal to the quantity of anti-peptone formed,indicatin~ a splitting of the proteid mole~ule into halves,the HEYl and AN~I ~roups. 't'hehemi group is most prominent in hetero-proteose,and if this proteose be Obtained pure and a~ted upon by trypsin,th8 hyJrolysis ~ill result in the formation of-more amjdo-acids then anti-peptone The tript10 digestion of protoproteose g~ves e result the reverse o~ this,showing the predomin6nc~ of the anti group in the molecule.~he digestion of sU~h SUbstances as ~elatine and antialbumid,which do not form he\erO-proteose,will form anti-pe~tone, and no amido-acids- Artifi~iallY the anti-peptone can be hydrolyzed osses,and some other undefined ~ompoun4s. forming h1ston 'rHF. HlS'l'ONB ~SES or PRO'l'Al41NES, arg inin, h is t t o m and lY6 in, are for~ed Whenever a proteid is pushed to the limit or trypti~ digestion.~hey are looked on ,as bein~ the essential nu~leus of the proteid moleoule,the amido-aciJ,and other ~roupings bein~ joined on as side ehains •. The hlston bases oocur mixed in 41fferent proportions in the s~ermatozoa of salmon,stur~eon and some other fiSh,and are easily· separated from another by hy~rolysis. LY~lN,the first base Obtained from a proteid,is di-amiJo caproio aela. C5Hg(NHZ)ZGOOH. ARG1NIN,so called from the beautlfil compounr it forms~ith silver nItrate 1. a .con~ugatlon . . . \ ~s of urea wlth ornithin, (di-amido ~aleric _ Le Lds on hydrolysis . •"he COmposltlon of arglo1n 18 aCl.d), '1t'.l"h 1 t y . . .,. NH2CNH-~4H?(NH2)2GOOH. ~ f; Histidiri,has not been assigned formula is CoBgN3 Z. 0 a structural . 'J'heseprotamines \'lill respond tlons.~articularly the biuret,in formula;lts empirical to se~eral or the proteid'reacWhich they ~ive a pink color. . • t When a concentrated solution of protamines bodies are precipitated. hol,these is poured into aloo- Tn a natural digestion the absorption of peptoDes,~EI;kes place b~fore th~ trypsin ean form protamines. p t a JUi~e ompuon d t a t on tr.(~ r esut t in~~ compounds. '!he s i mpLe flroteld is cb ang e d as above. tn the aBse of nucleoprote1ds, the nucleins,true and pseuJo, are dissolved and hy,ir olyzed.Coll~gen IS not directly aigested by trypsin but only after oonversion into gelatine,which is easily oon ver-t e d into e:{elatine p ep t on e s Fd as t Ln is cria.nge d as by the. ~astr1e JUioe.i'eratins art:' not decomposed. The an c r e a c splits APTIPfCIAL Preparation of the the P~NCREArlC products Plaoe 250 grams of fibrin c of p r o e ds and a c s DIGESTION. trypsin proteolysis. in a "2 liter bottle;pour upon it ~ ceo of dhloroform and add 5 ec.of one liter or water ~ontaining &atur at ej s o or um c ar eona t e solution and either ~~;or :-1 grams of fJan- , or e as po\vder or pancreas pUlp.Shake thoroughly' cork,anl1 !Jh'"ce in e thermostat ~'J.t 40 C. for t en \1ays.rrr-'8 mixture must remain alk3.line,and oa c t e r La j criang e be prevented by the a da i t Lor, of t nyrnoI or 0hloroform , if ne"'l~ssary. t,t t he en a of t hs f' r r s t :4"k hours, fi1 t er a few ~C. of t he digest ive mi xl ure an.i to t h e r i It r at G ad d hromine water.-~ violat color lndloates that digestion is progress ing. (8romine or tryptophan ~eaation. ) .1t the end of ten days pour the .son t en t a of t h e bottle rn t o a s auc epan ,aei,tulate fA.i.ntly ~1.tn acetic a.~i<itheat to boiling anu Llt0r.F;',apQre.te the filtrate to about I5{)-200 co.and a I Low to S~Etnd. in a oo()l ~~ace. Within a ff!I¥ no ur-s a large quan t Lt y of tyros an W~ll be c1epOS1t-e.d,usually· in the fum of very fina needles. Decant the mot ne r itflucr (to be use.' in th~ i-'l'epa.ratioo of Leuc t n ) from 1h~ t yr os In thro ugh 1 inen t ';ash hast ily bydeeantat ion ,'lith a small quantity of eol,t w'ater,brinJ into a small flask,andiissolve In about 100 co.of hot water to Which a little ammonia has been added.,f"ilter tne aoluti.on In an eVBporatin~ -hSh,heat over the tVaterbath until '"mmoni..a has blteD dri"en off and allol'l to cool. ~:xamine a. few or the ~ryatals <if tyroOBill UI1.i-ar the mloroscope; '~oll':lct the remai.n<l~ran a fIlter ~ash 'Ni-ttl ~ter and dry. Ty'rosin 18 r,groxyprlenyl ami,1o pro~rio.ni.e a-.:~d. . '"'H ~. OH v I,!} 4~.... C .. H (NH ~~~j' 2. ) eOOH Tt IS sraringl,y 801UblH in 001,1 water,more SolUble.in boilin,J VI \rater,~llTJost Insoluble in str~>niS al~ohol an,: quite insolubll/' in a ether •.. t IS rf>dl1"l;' solu"le In a 'I' .• i lk l' . ',.s,an: a "8 1es,hn'! In solutions Of alkaline salts. oJ . • J U - (j ,t> f ea",tlons of tyrosine Place a few erystala of tyrosin on a slide and warm gently-th6Y do not melt.~at ~ryste18 found in pus resemble tyrosin in ~en8ral appearan.eebut melt "hen warmed,and are insoluble in hydroohloric act.1. To a ~ery small quantity of tyroain add water and a fe~ dro~. turns rose-rad and upon or J4illons reagent. On boil ing thetmixture dert..tondin~ a aeepe~ red color deyel,pes.All phenols and their et1v8S ~ive this reaction. Perias reaetion.-Place a small uantity of tyrosin upon a \Vatch and h ~a.t for ti!lass,adJ & feW' drops or concentrated sulp.huric aeld an d pour into hale an hour over 8. boiling water bath.Allow to ~ool ,. 1f -ce. of water contained in a porcelain evaporating dish. 'farm "neutralize with powderod barium carbonate,filter while hot,e~aporate the filtrate to a few au. and a~d a Yery dilute ferric ohloride solution-a violet color. f'reparat ion of I.tF:UCIN. t'~vap(lrat e t ne mother liquor decant ell frOID t he tyros in er ys t aa.ls, , over the water bath to a thin syrup and examine microscopi~allY the seum forme~ on the surface.Tn this impure form leucin usuallY orystalli~e.s in r01Jl14.4 balls "hi·~h s now radiatlng linet.hBri.ng th8' mixtur6 int~ a tlask,pour u~on it se.erel times its volume of ~O p er-e en t alcohol, heat on the ivat ar bSU'1. alloW to eoo I and r i.1tar. Pl'he alcohol1e extract contains moat or the leucine F,ve.porate the al~ahol on the water bath,dlssolve the residue in water and boil ~ith freshly prelJared lea,;1hydroxilie.Allow to cool,filter,rree the (1ltrate from lea4 ~ith sulphurette4 hydro~en anJ evaporate to a small volume.rha leu~in ~hich 1s pre~1pit8ted on standin~,~~ best separated from the mother liquor by transferrin5 to a porous clay plate. Leucin (ami,1o-isobutyl a ee t ae acid.) G4H9GH(NH:3}COOH. is a ~onstant produot or the rtecomposition of proteins enzymes or ott'Hr hydrolyt 10 at:ents. As usually O-btained, in animpure form it cryst.a.lli&ea 1a r.Qun~1ed lumps \,hi en orten shO'" rad-iatiug IS t r iat ion When pure it forms White ):Sl.i.tteriD~ flat crystals • .It 1$ easily soluble in hot weter~le •• alQ 1!'1 ~C)ld \'ater.s()l~ble in aloonol,insolu~le ia eth~r. Reaotion, or leucin. in a .;11")' test t ube a ver·i 8ID811 t:'0rtionor leue1n, it SUblimes 1n the form of woolly flakes. te nea t e c ab""'e its meltln~ point (170 C.) it decomposes into ~arbon Jioxide an~ amylamine.tne latter sUbstance ha~in~ a onaracterist1~ odor. Heat slowly Place a little leu~in in 8 4ry test tUbe. add a piece ot causti~ loda(stiek form) ,one cmJlong an~ 8 drop or two of water.Heat until lhe caustic me •. l'ts;ammonia is given orr. Allow to cool,dissOl.~ 111 l 1it t Le water and ac1~ulate with 11il ut e sulphUr ic sc·t a-the odor .r valerisn10 acid ~s notaiceable.Leucine bY this treatment take. ip oxygen and rtecomposes into valerid acid ammonia and carbon di)xide. 01sso1ve a portion of the leuein in water,d~colorize if necesskry With animal chareoal,filter,make alkaline w'ith caustic s-Oda and add 1-2 drops of copper SUIPhaie solution.1ne copper hydrate ({hiah is precipitated at first diSS~lves on Shakinl3 giving a blue solution Whi~h is not reduced on heatin~ • •S~herors reaction~(OnlY applicable to Yery pure leucine )Eyaporate carefully to dryness on a platinum foil with nitric acia 8 small portion of leucin;the residue will be almost transparent and turn yellow or brown on the addition of caustic alkali.Ir this be again very carefully ~oncentrated with the alkali an oil drop is obtained,I'fhich runs oyer the platinum in a sj?heroidal state. DTASTA,'IC ACTION Off'PANCRRA'fIN. Prepara some stareh paste (A) as l.1irectedun<1er salivary digestion.Dissolve otte gram of paner-eatan in 500 cc.of water(B) and after s t an dang at 40 C.for two hours,filtertha solution.i'ix in a test tube equal volumes of (A) and (8) and heat at ~!40 C.'l'he material becomes transparent,reduces Pehlin5s solution anJ is not colored blue upon the addition of iodine solution.Repeat the test using a boiled solution or pancreatin. The ~ancreatin solution itself Should be tested ~ith Pehlin~s solution as the commercial article is (re~upntlyadulterated ~ith sugar. Recognition of a fat-splitting Ferment (SrF.APSI~) These experiments must be made with the fresh panoreas. Shake a gram or two of butter, fat with a few ee -cr luke warm water to which one drop of caustic soda has been added,and after eooling skake with an equal yolume of ether.P~ur oCf a portion of the etherial extract on a watch ~lass and allow the ether to evaporate(neutral butter fat) Obtain a pl~ce of fresh pancreas the size of a pea and mix it intimatelY by rUbbing with the butter fat on the watoh glass.CoY~ with an inverted watch glass or t h s same size and place in a thermostat at 40 C. In a few minutes the odor of butyric acid may be recognized. nrind part of a pancreas with a little water to a thin paste,and divide into two portions; (A) and (B)~Boil t c destroJ the ferment th~ portio~ (A).Shake a gram of butter fat with luke warm water, add a few drops of rosolic acid solution &nd enough dilute caustic soda solutio~ to turn the indicator.Mix equal quantities or the Cat mixture'~ ~iA)' and (B)Ir the resulting mixtures are not plainly red add drop by drop dilut e s o d i urn carbona.t e sol ut ion. Ke3p th'tt mixture at 40 CQ for 12 hours.The mixture in (A) does not ~hange its color; the mixture in (8) turns y-elloW'due to the acid libera ted frolI!the butter fat. In a similar manner the d1astatic and fat-splitting properties of cystic flUids,l'{hichare thought to originate in the pancreas maybe t asted ., 'rH~~L1VER. The functions of the liver are digestive, excretory and assimilative.Tts digestive and excretory functions are carried out largelY by its'secretion-the bile.tne digestive action of bil~ is very slight,being ~eaklY dlastatic,anJ a.iding in the emulsifying ~r fats .. As an excretory organ the liver is very important.It removes thO effete haemoglobun,which it converts into bile pigment,and the waste products 9f protein metaoolism,som€ of~hi~h are formed in the liver, itself,oth'21rs are der aved from theblood.'l'ne liver also has the valuable function of modifying or destroying eertain drugs and food products,dangerous to the organism.This fun~tion is of the utmos t irnport an ce in prot eet ing the bo"iy agains t a ser ies of more or less poisonous products formed during digestion. Tn respect of nutrition its functions are most varied and complex.,'i'n e liver elaborates and mOttifi.esalmost every product of digestion brought to it by the blood through the portal vein; changing not only the peptone and sugar,but also tr.ansforming the products of deeper cleavage,the amido-acids,histon bases and ammonistand carbon Jioxide?forming urea and bUilding up more complex' bodies. This activity is evidenced by the formation of glyco~en,the excretion of bile acids,and the forma.tion of urea. Urea and uric acid are found in larger quantity than in the blood,th& xanthin bases,lactlc acid ani cystin are found in considerable quantity. GLYCOGEN. Gly;~ogen is a poj ys ac cnar Ldej hav fng properties intermediate between starches and dextrins.'l'heliver builds up 5lycogen Cromthe • simple sugar absorbed form the carbohycrate from the d1~e.ted material ..... a rule. but oan \fhen the .. te~ is free trom this materia,l_ It o.csur. most abundantly after a '!l~ftl ri~t't in carbohVdrat •• , rea.hing it. maximum 14 or ttl hours after eating. 'l'he an'ora~e quantity or gl)'cogen 15 from 1 to 4 percent of th.•·liver v/eil!Sht.Aamall quantity of glycogen occurs in the mus~les .and its presence can be dete~ted in almost e~ery tisaue ot the body. <Hyeogen is an anwrphous \vhite t88t61e88 and o.lorless k>0\fq.r.lt ia solUble in water,the solut1on is dextrogyratG.5p.r.I~J.;~.lt does not reduce Fehlinge solution,and i8 not decomposea bY boiling with caustic alkali.By \Uastatio enz;}tmes it is eonvt~rted inlo maltose.and dextrose,end forms dextrose when boiled with dilute acid. Preparation of glyco~en. Mince 50 grams or tresh liver,and add to it ~500 cc.of boiling water conta1Din~ a small quantity of aeet1c 8~id.Strain the~paleScent solution through muslin. The solution contains besides gly~ogen,some prot6in.~0 free from the 'letter,conoentrate the solution by ev.poration to 8 small ~olume, and 844 a1ternatelY A. few Ilrops or hyc1ro~hloric acid and of potassium mer~uri~ iOdide as lon~ a preoipitate is forme4.Pilter a portion or the liquid,and t es t with 8oci4 and iodide i .tQIDai(e sure that the protein ia completely removed. When this is tne oase.filter,rirst through mualin then tnroufSh paper.alld add to the filtrate 2 volumes or allJoho~tirring thQrQu~hl)i.Pour orf the aupernatant liQui j an d 1t8.sh the lireoipi tated glycogen wi th ;;5 per cent aloohol by d~cantat1on.and cov.r ~itn abMolute al~ono~or an hour or more.Colleot tbe ~lyco~en on • f~lter an~ dry between rol~ pa~er. or filter Reactions or ~l Y"4ogerh Pissol •., 8<1•• tllyoo~.n in \f8ter bY ~.ntl. .solUtioD-rea.blahoe to solUble starch. Tv a portion of tfl fJ heat. Ano~e.le.c:ent 8Qlut ron a4 a few drop. or iodine. A re44ish brown eolor for ... -Resemblance to erytbrodextrin. 'Hotl. Gother portion or the sol ut ion with Fehling. solut ton, -no re4uot1on ooeura. '1'0 some gl,.40tfOl1 solution a4 a rew 4ropa of dilute hydrochloric "e.ei~ an~ bo~l;"n~ol Mel neutrallae.'fo erie portion ad iodine solutio to another a4d 'ohl1nga solution and boil·.'rhe glycogen is s"lit by this treatllMitnt. To 80m. glyoogen solution a4 Oft$ co. Qf _al1v. and keep the mixture at 40 c.ror ten minutes.At the end Qf this time test a portion or the solution with io~1ine;another portion with Fehlinge. r 'rrie bile is arm x t ur o r)f the s ec re t Loris or the liver cells an4 t~e muous secr(tert by the tlanJs of the biliary passages anj by the mucosa of the gall blc,!inr. \on;n:;l bile is a t.;olJor! yellow to' olive greeD colored liquid,uith a faIntly alkaline reaction,and a sp.g ..ofabout TOIO.'f'he avorStse daily quan t t t y ts about 760 cc s con-s tainlng about 2 percent of solids. Its chief constitu8nts are :_ Bile pigments~bilirubin ana blliverdin.Bile salts,glycocholate'and taur~Cholat8 of sOJium MucuoUS,Which ISB complex muaoid nucleo~rot0iJ.~r01~sterin. Fats inaluctin~ leclthins,and soaps~Inorganio salts;aLout ~8 peroent,consistin~ of sodium chloride and phosphate with smFll El:1Ount of SOodi.lln c ar boriat e Lr-on pl'losphate,c81-cium salts and occas ~n.El1y coppel". The'secretion of bile is con t t nuo uaj eue a t s d i s etiar-ge into the duo4<en~ is intermittent;the bile b~ing stQred in the gall-bladder unt il us.e a, '['he rate of flow' u; irr'6gular. and influenced chiefly by taking food,increasiny 4W"i.ng 4ig~stion and fal1iJ:1~5 wh en food is withheld.The dri!l1kin~'Qr large quantity O!,'<"Fter ;~auses ::tII; 6 j iner~esed flQ" of 'bile,and intestine is a po.~rfUl the stimulus ab ao r'p t Lon 'Of f)i.le salts to t ne s"tt~l"'oeti'O:n. from the 'l'HE BILE S~I;'rS AND ACIDh.-" are the SQ,,1iua ae.Lt s (If ;;lYl:o.;ooli.c an" taurocholio aaitts.On fl;V'1r'Glysi.s glY':Q4hGli~ ri.:.iJI yie.l4s oholalioac id and glyco~o11 {ami.1o-aeet s e HcirlJ" T.l'n':r-vo~ol.i.c a-ctd yiel dB In •• ~.i t j,(:ITJ t c cho La I ic ac 1d t aur- :i.ne (ami JO-'lt'hYl sulphonic a~ul). Ch'OLAL t o ;J;'tlJ o c cur-s in t ne ur in e Ln i:;{~rU3 ~its compos it ion is C Iif CHOF{~N ~~,~ti (~InOOOH 2:3 .. 'l'he t"'st.~s :"0"" ttl,,, r<t..~~)gniti'O~ Qf th~:Me at:i.J::; c.rC given ,rith the ,aostl;y' the. 4irect1~ns fGr the e~~~liDntio~ af bile. BtLE PIG~'''~S ..The bile pigments ar{:# Dl1m-'::1"QUS b'lt ".ult of post mOl't(~~ ~han5e,or GeoOt1t' in ti:'-e$I(!l!CS e.a11.¥ Th3 important ,-..Ii, ';';".'.18nt-iil P;l'r, 'i~l "r">"L'n ,-;;-,"'1 h;! .fC' ~ ....... "...... ,_ s. ""~..... _...... .., ..... '-J, fiIleIRUBi:N, is a reddish it Gloaely l'€S81T:lbies,.lt reaet i.«1s} • yell~w tdi'l1es '," .. oJ• .J- c;,r'~ .. ?'hY~'Siologi ... "iV"'l';'.'... ,,'w ." '. " .~. p.i.g~nt ~ deri.ve~ (:'011<!k1.e.t:~etinlllfh.i.oGtl nur:Jle:t""ou..sGOhH~"S w~en ~){i.~.!.7thi .. BILIV'RHDIN is form~l4! ~eQ ~tn ~.lkal ine 'Solut Ion 'Of bil iru-'in expOsed to the air,or otherwise mil~lv oXiJized. !Sdo;' 1a r;.aner2.1 \iiHh a (A).Th~ (8). './ ) ",.l.. -e 'J t:J .... .. J bile <> car '.J tn e follo;~Lli~ of bile,v~rifY portion reaction of Mo i/8;ipitate 1\1 'or'o"l ;}lV':OS i"1 (. tests. Sl:i811 either _8 neutral is pro(lUced by prer'i(litate-Lluc;in sli~htlY nl~all~e, boilHlg. nucl..::-al(1)rnin,·J(!lorl.~.s . .rct- .. 1 t'"'" ~.I or st[",tCJji;'l~ll;=O; t',3r~bile 8P..lt3 <.~f!' (D). ~lkBl~as ~h&nie the color but ~o not produce (E) .e ~CL'Sih\3n 8d<.;811. slowly i)reclf;ltatl~ c,t fIrst a fJreC:~jJita'>::" b.;lG IDucin:tn;::';:1 I gaT i \lID ~ h lor i ,1e ; ( H'), I cholie .,' e c o g n l't'1' (}n of '10 200 c cs o f en ad Ij e (1 t0 a precipltate. aciO:i1ves (G). the salts of h l'/h the - bile salts,<.1.nd the ox bile metals heavy In an an alkaline ti.Le ·.>,V8,poratin~ a o r os e dish,aJd :jO,J;lDS Gh~l.r;~081::"liX t nor ougn Lv an1'~vaporat9 to .rr yne s s ,'''',t''''''. bat' h P'~"rlO<'C> th'" ..n v j":'><.!ldUpc"D'\ \10w,19r as finely ~:J. -;'j v \J • ,'--' u.,; ...... ~., .~ 1 ~. -' t"' . 1. j .. 1 •. ~, .... ,1 _ij~nir15 in general D'FJ.l \ ,;Uuf sulutiun ovo,: 8:::; ~.... or t an i: no ,j[.:.,'.r"j,i:l',~ - mortar1place in a dry fla.:;k;an<.t extract with 8bSo~ute al,:;~)h(jl ~eatin~ o~er a water bathaAlloW to cool;f11ter ·into a dry fl~sk~ ad~ 8n~U~h ether to produce a permanent cloudinass,0ork1anJ allow to stand in a cool plate fur 24 hours.~he blla salts crystallize In the form ~f White silky ne3Jles(Plattners crystallized bil~") Co Ll o c t t h a e r ys t a l s on a filter anJ dry,Use a erie per cen t sOl: ci,,:, 10 8. l t ion tOl' t n e fe,llo\"rinr! t es t , Pettencoffers test, '10 e r ew c c s of :) drops of a ten percent solution tUbe inulineJtallo~ three or four the solution in a test tUi.,e:u-1(i r of cane sugar,t 1en hclJtn,s, th'~ oe~of eonoentrated sU1J~uri~ to flo,v do"m the side so ttU'l.t the acid forms a 1::<:"<31' Cit H,') bottom."·]h"lre th-3 liquids meet a purple violet col,)y dGv:Jlci-,e0~ Holdinf~ J:rl'3 tU(J8 un(h~r a stream of cold '.vater ,,::r,?,Ju811\ mJ.x ::'h'3 contents-a dap purple solution(avoid much hsat).lnto 82Gh of two test tutes (A) c~ntatning a few ccoor ~12cial acetic acid,anJ (B) ;;onta.:Lnin"J a fe'~'l ,~;.;,or alcof10ltJ.Jonr Fl sma,].l l.;llentity of tfl.'::: lJurjJle "oi,j sol ut ion. The solution in ,~) s~aatro50o?ically;~iv8s ~hOWS a ~reBn fluorescence;and when eXEmined a bnnd in ~rBen.The solution in (8)s~ows imffl8.:1iately after m:i'iHn6 th';; same ban:1;iJjJon 8taPdin!~ the solo.ti<c~n turns br'own;nn<:t>";ive8 two bands-one in io5reen;the ottll-:)r in clllBo Pet tenkoffol's test 1S 15iven by thebil'3 direct ?RDLl due to the presence of cholalic acid. nl:-COC]lOIic aci,j;{''Ln be si3tJarated from taurocholic ing to a watery ~olution ether,snd enouL5h sulphuric is 3~id a;..;parentlY bY:idd- of the bile orystals.a few drDps of acid tocause a ~louJiness.On ;3tHnd.in,~ such a mixture ja~oslts fine needles of glYCOChOlic acid. When bile is boiled for several hours with hydroChloric acid, for Seversl hours I a dar~: resinous body is thrown out of tn~ solut.ion .. 'I'his black bOuY~\"hich becomes brittle on coolin,-~,ls dyslysin1T.ile e.nhydri ,~e 0 f"~(..) 1 f' 11, C 8 C i ,1" 'l't- '''! ." ],;(",0' r:~)l i'~ ',r, d t ,?u:" () r;:'::..l i. l:: f' C i,18 are hydrolyzed by tH.l~ l,·'~~il. :c~to':n::; e;l.~(;();;oll8.n:J t.aur ar. formed are left in the solution.'fo separate them the solution is oon een-e tratec a.nd poured into 15 volumes of alcohol,W'hen the taurin is precipitated. t - EXAMINA' JON OP BTL1ARY O~LCULt. Boil the freshly powdl3red stones with water in order to r emov e tra~es of bile that are usually present;fllter and allow the residue to dry"F.xtraet the dry residue exhaustively with a mixture of' ether and aleohol(equal parts by volume) filter each extract through e dry filter into a dry flask;and evaporate the united extracts to a small volume.On standIng or possiblY during the ~vaporation,cholesterin crystals are deposited. (Examine under the m i c r o s c op e l 0 free the cholesterin from fat, dissolve in uO fH~reent aloohol (25 ce. )add a small piece of caustic potash,heat in a flask over the water bath;transfer the contents of the flask to an e~aporating .1ish an d evaporate to dr yness .1'ake up the res idue in water; and shake in a separating funnel with ether.Separatethe ~therial from the alkaline fluid;and allow the former to evaporate. 1'0 on a slide;cvver with a cover 51ip;ard brinle(enough sulphuric acid in e on t ae t with the edge of the slip to fill the space between the two glasse~.Then brlng a drop or two of iodine solution in contact with the ed~e of thQ 51 ip-tt-8 c rys t aLs ar e colore d graduall;'y' er own then v ~olet light blue ..gr aen ,86.'rhese colors do not al'l{aysoccur in the order gi'fen (A) Place a few drops of cholesterin often p rec ee ded or followed bY others. Place a few c rys t.a'l s of cholesterin a n a small porcelain dish, with a few drops of hydrOChloric acid,and ferric chloridecEvaporate over th~ wat~r bath. (Blue color.). (0). Dissolve a little cholesterin in a few ce.of chloroform;add 3D equal volume of concentrated sulphuric a~id~and shake thorough1.y.'l'he sUlphuri~ ac i d solution un der' the chloroform exhibits a ~reen fluorescence;tne ohloroform solution turns first red, then violet.Tf a little of the Chloroform solution is poured into a wet test tUbe;the solution is decolorized;if concentrated sulphurio Ecid is then added to the contents of the tUbe. the original color and are (8). brought ba~k. Tn & very dilute solution of cholesterin the reaction is someWhat different-yellow at first,then red coloration of the chloroform~yel1ow coloration of the acid with green fluoreseence. iD}.TJiebermans reactiono·-Dissolve a IHtle cholesterin bY heating in acetic anhydride;and after cooling add concentrated sulphuric aciJ.The mixture gives the eolors;~ink,red,blue,and fina111 green. IS are hydrolyzed by this treatment.The glycocolland tBurin formed are left in the soLu t i on vt'o separate them the solution is concentrated and poured into 15 volumes of aLc onc Lj wnen the taurin i~ pr iC! C 1 pit ~'ted , I 0 EXAJ.'. 'N.A'l'ION OF 81 IJl ARY CAl.CULl. Boilthe freshly powdered stones wa t n water in order to remove traces of bile that are usually present:fllter and allow the residue to dryeRxtraet the dry residue exhaustively With a mixture of' eth~r and alcohol(equal parts by volume) filter each extract through a dry filter into a dry flask;and evaporate the united extracts to a small VOluffi8.0nstanding or possiblY Juring the avaporation,cholesterin crystals are deposited. (Examine under the m.i e r o s c op e L, ' r r ee the crioLe s t er f n from fat 1 dissolve in bO percent alcohol (25 co. )add a small piace of caustic potash,heat in a flask over ths water batn;transfer the contents of the flask to an evaporating dish an d evaporate to dryness. Take up the res idue in wa tar; aftd shake jn a separating fuunel with ether.Separate the etherial from the alkaline fluid;and allow the former to evaporate1'0 (A) Place a few drops of cholesterin on a slide;cover with a cover sljp;and brincl enou~h SUlphuric acid in contaet with the edcle of the slip to fill tha space between the two ~lasseH.rhen bring a drop or two of iodine solution in contact with the edge of th~ s I i p-r t ne c rys t a I.s ar e colored graduallj' or own then violet 1 19h t bl u e ~gr e en , gB. Thes e colors do not a Lways occur in the order g 1v en and are often preceeded or followed by others. (B).Place a few crystals of cholesterin in a small porcelain aish, with a few drops of h~drochloric acid:anJ ferric chloride.Evaporate 0'1 er th,' Ws; t er bat h ~ (B I u e co rcr l(C). Diss()lv8 a little cholesterin in a few cc.of chloroform;add an equal volume of concentrated sUlphuri~ aciJ)anJ shake thoroughly.The suipnur tc a c i d soll1tj.cn':nder t rie cn Lor of cr'm exhibits a ~reen fJuorescence;the ctlorcform solution turfis first red~then violot.Tf a little of the Chloroform solution is ~oured intD a w~t test t.uee j t n e s o tu t ron is decolorizea;if concentrated su Lphur Le Ecid is then sdded to the contents of the tUbe, the original color v ~;rought ba ck . In e very dilute solution of cholesterin the reaetlon is someWhet different-yelloW at first,then red coloration of the ch1oroform~yellow coloration of the acid with green fluoreseence. (D).Liebermans r8actioo.-Dissolve a little ~holesterin by heating in acetic anhydrid8;and after cooling add concentrated sulphuric aciJ"The mixture ~iges the eo1ors;~ink,red,blue,and fina1l' gr~en. is · ~he residue of the stonRtinso~Uble in ether and alCOhQl,aonsists of the inor~enic salts,anJ ~ile pigment. W&sh the insoluble r~siJue ~ith ether,cut off the upper part of the filter papRr on whi~h th~rA is usually somA cholesterin;and wash ~ residue with about 20 e e s of' ,Hlute hydrochlorio aci..", pourin~ the filtrate repeatidlY upon the residue. The filtrate contains ~alcium salts,recognmzed bY addingammonia aeetie at;}idand ammonium oxalate;possiblY traces of copper,reeognized bY addin~ a few ~rops of potass1um ferroeyanido to t~a hY-' drochloric acid solution-~uprie ferrocyaniJe. Wash the r':3sidUerernaitlin~on the filter paper 'nth wat er until t r.e 8si.j is remove:i;~lf'.eethe filter a nd residue in aNurm place, illth unt i I dry;eut into pieces;place a n a cr y ~:rlenmyer flask,'ofarm B I1ttle chloroform, and filter through a dry riltero~he filtrate dontains bilirubin. pour a small quantity upon a watch glass$sllow the chloroform to evaporate spontaoeoUsly;anJ examine the residue mieroscopically-ill d,efined rhombic platas,or prisms- GMELTNS R~ACTION ! This is extremely delicate and may bd ~pplied in various ways. fA) .. /:J.ft3W c~.of the chloroform solution are placed in a test t uo e and an equal amount o t' yello" nitric acid added bY pouring it down the side of th~ inclined tUbe in such a manner that the liquids do not mix.At the line of Junction colored rings appe8r,bain~ yelloW nearest th9 Bcid;and progressivelY red tViolet,blUe,greBn,passin~ upwards- (8). 6 few ~rops or the solution are placed on 8 porcelain slab; and a (lrOp of yelloW fuming nitriC aeid is brought into contact with it. A play of colors is observed at the Junction of th3 flui(1s. (0) _ :::;hake :Jart of the ehloroform sol',aion,'1ith a c aLu t e so lium carbonate solution-the coloring matter is taken up by the alkaline sCiJ!utionthe chloroform losing its "olor more or less eornpletelY· ~his action of its ehloroform solution~jistin~uish0S bilirubin v from oth&r pigments found in the animel'bod , (D). Exp ose the 8,1:<',,'1ine solution of bilirLl'~ir: t o t h e [11",' ::,D open vessel-it turns green due to t ne fUrL tic, 'J U;" 0i~i', r .i n , BI.,OOD. '}'heblo()'Jcan e e e ons t uer ed 8.S a fluid tissue.'fhB cell C;LIi:; suspended in the transparent liquid intercellular sUbstanc8,-the plasma. ~he blood is alkaline.The alkalinity ,oelaulate4 as sodium carbonate IS about .5 ~ereent.The alkalinity is due to tne presence' of alkaline carbonates and phos~hates. �rhe specit'ic gra-tity' as Tr.Hw..'ht bY &.dding A. drop of zol; ir -t"t sinks to the bot floats on t~~ surface,add liqu1d.~hen determine the 'ltt.'" oonstituents of tne '1esaels anti organs,markEhtlY blood oonta1ns 22 par~ant ide, bY volume: venous bloo.t betwe~n I~o and 107';),8.n«1 can be deter blood to a mixture of bhl(#TofQrm and ben tom A.\tet mora ohlorotorm,lf trt& clfop benzol;unt1l it floata m1d~ay 1n t~. ap.g.of the mixture. bloo,1 ,vary,in tt'H~ blood of di.ffereDt in t ne veins anu arteries."he art'3rial Qf oxy~en,and ~O percent of uarb~n Jioxcontains Y.(u 5 fJercent 0, an.l "'b peroent CO2• "'he ~a.e80CI1Ur in loose oomb1na t ion nod t'ree in the plasma. when the clood of ma~1mals 1~ remo.ed from the vessela it is converted"more or less rapidlY ,into a Jelly li~e n~s.,bY cosgulation.~he ohan~e is the result of the aotivity of a ferment, thrombin,existin~ in the blood in an un4 •• elQpe~ form,on f1br1nogen.formiDg fibrin.The fibrin eneaOK1 •• tne o~rpua4le. in 1t~ rn8.~es.an4 tl'\sre ia '~r8duall, pr ••••• out. ol.ar Y~11ow rlui~,tha blood serum. 1he coagul.tlGD or ~lgQ4 •• n ~. pt•••nt.4 in •• rlou. ways. After th13"iraJeotion Qr a1b .... e intg a •• 1n or a tkI.s.t.h"bloolo1 do\}f.inot coagulate on le •• 1D~ the ~od1.Jr t~. bloo4 be ~aWD 41re4tly into a satur.ted 80lut1on Or _.ntl.twa auljtllate.inth., proport1un or a ·tot.or1nto a .olutton ot jiU, ..... v.ala'e.80 that the mixture <Jontai". tlt l ••• t. t iJere..ftt or o.al.,e.no'.g-..culat t-., tale. pl •••• The ~l...a obt.1b~d rrom auth ~Ioo•• i. &no~ .a pepton.,.alt an~ oxa1a'te plasma. Tf th~ b1CXld ia De~t.n ,*Ul"ln~ ooafjult.. tu,ft, t ne fH.rinatJparatss tn thr<ta4. or th~ 11'i\1141~ ,1Hfibrinate4 ~l00d.fhG ~r6.8nt1on or oo.~ul.tlon of ~luud by .alt_,is ,tue to the pre.ipt tat iQn or 4t8141um. -. The b1004 oell. arll r~4. whlt~ .Ul0 Uut ~lQv,t plaqu" •• 'fhe ro4 oOell_ !)ontain 1'l.U.~~lODla. a oom~O\ln(ipr.ot.ll1, 4vn\a.1Il'.l'n~ _irGn~a,n4 h •• lhg U'I& prop~rt)" of rOl"11l1Dat a lQQ. t! OCiHDblnatJ.vn wl t: h Qxygen.~~e dlrrerenoe tn oolor or .enOU4 an. a!"tarla1 01QQd 14 (ftl\".ea,an,1 lar~(,ly ttue t~' the dlrr.rentn.&4IOIVglotl.i.n •• ~Qntaln .lar~. ~unt or nU~1.o~rot~14,~~~ The 1~u4ooyt8. .,lyoog$n an4l!1 tl".48 of myosin. rl'h,~ pl&81l8 oonta.tn. 3 ~rotlJli1.tOn. ' ~lfJ.ll1ts\JrwrA albUIIln,ani two ~10bul~na,fibtlno~.n and •• ~UQ~glooUllh • ...Amon~ OU\~r.bOCh~" fllllt "'lth, 1" tne • ..,rum.-,te '1!"&6,uric acid, 3r"et~,4arb_&',par-al •• tl0,.~'h' ~lptlU"~d e.O"".,wrnol1is. and xanthin base •• Ut!xtroae ani 40(". ~re .~le" .I.ltora ..a goOOUr lIlormally'.T.n ~~4~tlun to the fibrtn rerme~t,blood tontalns a ~ltaolyt1~ and an lnvert.i.n~ vnzyme. (A) Defibrinated blood. General reactions. (A). Litmus paper-Moisten a pie~e of litmus paper with a concan trated solution of sodium chloride. Puncture the end of the finger 'lith a sterilized 'needle,placI:3 tM~ drop of' blood obtained on the Ii t rnus paper t er a row secon ds and t hen was n the blood fro,ll the paper by means of the salirie solution~As a ruld the alkaline 'reaotion aan be clearly seen. (8). Ilitmus 801\1.t1on. Pour a La t t Le red litmus solution on a piece of porous plate,obtain a Jrop of blood as abovB,place it on the red' surface fOI!'" Ft r ew seconds and then wash off wi t h running water a b(reenish b Lue spot is not Lc eab Le Where t rie -Ir op touched Gui,acum and turpentine oil. '1'0 10 oc s of' wa t er Elt:d a f'~\" urop s blood,then a f,,;'4 c e or t i riot ur-e of iSuiaaum an o wix,~"inally add a faW' i,~c.of ozonized turpentine oil and: shake t ho roughLy -tne mixture is ~olQred blue. (D). Hydrogen dioxide. Add to une cc.of blood two or three cu.ot hydrogen dioxide-intense frothing dUe to the esoape of oxygen. The oxyhaemogj o o rn is d(~!jomposeJ. (Catalytic a c t Lonv }, IG}. of v Spectroscopic examination- dbser ipt ion t ns v iQlet ri~ht. assumEod to be on th{1 observers Tn t h('! fol1ow'ing ana of the spectrum, is (A) Oxyhaemoglobin. Dilute 10 cc.of bIooa ~ith 90 of water and filter~~laQe ~art of the solution in a test iUbe and examIne With t h e ap ec t roe cop e s v'h en the solution is so concentrated the spectrum will prObably be entirely shut off as far as the yellow or orange but on ~radually dilut1ng wlth water a spectrum is finally seen Which ShOWS two absorption bands to the ri~ht od the D line.The right hand band is broader faInter and less sharply Jefinnd than the other and the color of the l~ght Which emerges from the left limb of the Ler t hand is yellow.'llhen the solution is tur t n er (jia:utet~ the ban-rs disappear s amu l t eneo us j y. / (8). Reduced haemoglObin. When a solution of oxyheemoglobin is tra treate~ with a reducing agent the colorin~ matter loses oxy~en an~ is changed into haemoglobin. Stokes flUi(1 is the most sui tabla reagent for reJucing;and is prepared as follows. Dissolve 3 ~r8ms of sa~cted orrstals of ferrous sulphate in eold water and add a cold aqueous solution of two grams of tarta.ric or f.Jitrica )d. Make up with ~ater to 8 ~olume of 100 ~e.a.nd immediately before using add amnorlia until the precipitate \Vhich forms at first is redissol~ed.The solution should not be exposed to the air and ~s unfit for use 24 hours after it is ~repared. Pre-pare e solution of oxyhaemot51obin \'1hichIvill snow the cha.raot er rs t re absort>tion bands.Allow 8. few cr-ops of Stokes solution to' floW into the solution in sueh a manner that air bUb~les ere not carried down with hte liquid.The colQr of the solutlon ~hanges to a purple or violet and the s~edtrUm shoWs a s~ngle broad ,diffuse and. p oor Ly define4 bBnd as though two oxyhaemot5lobin bands naI gone together and had been displaced to the left. When the solution is agitated with air its color Changes to bri~ht red ana the dpectrum is that of oxynaemog Lob m(C).Mnthaernoglobin. To a dllute solution of blood add a drop or tw'o of a fre~hiy prepared TO p ereen t solution of potassium ferricy anido.'l'he~olor of the solution becomes brown and the spectrum s hows an absorption band in the red and in addition two uan-ts of more or less uneertain character \'1hichoccupy the pos i t aoo s of the bands of oxyhemoglobin. When the solution is t reat ed with Stokes fluid the methaemoglobin ehanges to haemoglobin,Oxyhaemoglobin bein~ formed intermediatelY and on B.gitating with air the haemoglobin is ~hanged to oxYhaemoglObin.These changes ~aneasilY be' followed with the spectros~ope. (D). Aaid neematin ~o a few drops of undiluted blood add a drop or two or aee t t c a 0 iii. '}'hehnamoglobin is broken up into a his ton call ad globin Bnd a non-proteid substanee ealled haemin.rne solution whioh reSUlts is aln~st black but on diluting with water is seen to be red.Tha spectrum has a band in tn0 red almost. but not quite eoan 0 idt,:,nt \l7i th the corresponding band of methaemo~lobin. 'l'he- . , his ton under these conditions is of course further decomposed. (F.) •. Alkaline na ema t m 'fa a porti.on of the acid haematin sofutaon b.dd sodium hy,jroxh1e un t il the preoipitate wnich forms has redi.ssolved.The solution will be alkaline and if properly Jiluted will shoW a poorly defined band to the left of the n line.It is usUt'.llyobser'l1edhowe'l1erthat the entire speotrum is absorbed except the red. (F}.Reduced haematin (Haemoehromogen)Reduce a portion of alkaline haemetin solution .. <lithStokes fluid ana after f/roperly ~1iluting examine with the spectroscope. Two very dark end Sharply defined bands are seen betWeen D and ~ which seem to be coincident ~ith the )raud5: p r ... ·,d"LL~Gd by o;~yhaern(Jg!.J)btD.It will be noted however, that emerges on the left of the left band is plainly greei1oBY·iilutin~~ t he cvlutici.! with TJlai:s.:.· the b3.r!~; on t ho right may be madE t~ disappoar,while th0 ather ~and is still very dark. HARMfTOPORPHY2TN, Place a few oeD of nODc8ntratsct suIDhuric acld the lightvilJi(;.'1. if In . a t es • th • estt J:ut.,e s t i..r r.n t o t118 a c z. ef a drop or~ b I 001.~ an d1- exemano sol~tion.Two ba~~s are seen on opposite sides of the D line, The one on t he left. darke~ on ;he :.~ right La: ....:;:·Ovi t ho s~de 0113 on the rig11t IS broad and muen than on the leCto CARB0NMONCXTDE HAC~On1GBIN. Pass aSLGw C;J~'r':mt of illlj~nii1ating gal::' ~wh~Ch conta:'.ns about 7 pdr~ent 8f c~rbonmonoX~de~thrcugh 50 eeeo: blOOd until the color of [he bloo'i ia brig!~t r0~~ Spectre,s cop i c t es t e .·-'Exe.min~ a p or t ton of 'l'he banJ!Cj occupy nearly the s a.ne ~Ics:'..tif)n og!obin.rreat bands pei·s"5..2 t the so:utjon with reduci~g t ne carbonmonoxi de blood as the bands of ')xyhaemAgents (Stokes fluid)?th&' v Ohem:1:;a1. tests" 'l'wo ~olutimTs are requ:i.re~·-a solution of oxyhaemoglobin .b Loo d (A);a solution o r carbon monoxide bloOd{B). IQ '1'0 a 'fev'! cocof ;A) add one halt its Volume of st!'ong caustic potash solution.-Fcpeat th& ~xperiment with (8), (A)deposits a brownish r e d 01" reddish grt38il fJrecipitate, is) usually- deposits brilliant red.-Tn dilute sollltion (A)1.18!-iOSlts a brownish g r ey , preclpitat~71 {Aj i n dilute s(jlution}un"~i~r t h e s e circumstances becomes murky I"'tllc:ren tun1S light reJ,'lhe liquid ,1eposits red flakes on sten~ing~ 2. 'l'o TO Ccoo!' LA) ferrocye.n:idc;and add 15 (;~.·of a ~~O percent 2 t":·"o~' ac e t t o ~1;,;id",-·E8pQat a solutif)(\ I)f" potassium tile e;~peime!1t with (8) and a!ter allo~ln~ to stand some time compare the colors; (A)i§ greyish bro~n or green; (B)giv&5 a bright red colorb 30 nix a small qu~-mti~y of (A)vrith <1 times its volume ofl'/ater.'l'o a p or t ion one percent Gf tnl:::: diJ.ute solution add three times its volume of a the experiment with (B) scl:1tioTI c1' tanninQRepeat Haemin test <Bl00~ stain tcst,)Evaporate aarefully a small drop of dilute sodium chloride solution on a slide~?lace a few particles of the suspeoted m~terial or a drop or blood on the thin layer of s~lt crystalsa00ver ~ith a cover glass and bring enough glacial aeet:i.c acid on the sliJe and in oontact with the edge of the slip to fill the space between the glasses~Heat until bUbbles of gas begin to form ~As ~vaporation pro~eeds adJ glacial aceti~ acid drop by dro.p fr(m~ the edge of t h:e Cover glass, whGn a reddish brown tinge appears rBmo;e further [rom the flame and allow the acid to evaporat€:< iEJ-'~DmirJ€r1lIDiCroscopjcalIY" ~, I 'l'he blood as wej.~. arc e ar ouc fluids arid c.not ner ~.nsol'.1blee'l'he serum c on t e f ns on e proteid form.::1' is serum ~lbumin solUble in water the latter serl~n ~lobulin {held in solution by the salts of the blood~'1'he two pr o t e s ds mar bo pr-e c Lpi t a t s d t og e t ne r or s e p ar a t e Ly by using c9rtain saltso To 25 oe,,()f blood serum in a mortar a<.!d 20 grams or ammonium sUlphate and rub with a pestle until the fluid is saturated with the salt~8oth p r o t e a d..s ar e pre~i~:'.'tated e ompLe t e Ly -PdLt er' through a dry filter paper,aoidulate the :iltrate with aoetic acid and b011-no changeD I '1'0 25 ee ..o f serum ad~ 25 e c s o f a s a t ur a t e d s o j u t i cn of ammonium sUlph8t~;rilte~ and wash with a Eatura~ed solution of thB salt. Serum globulin is precipitated an d serum albumin is in soj ut aon , Hea t the filtrate to boiling·~serum aLbumdn is coagu],ateaoPlace a little of the globulin in a test tUbe and pour water on it -the proteid d1ssolves by virtue of the Emall qua~tity of salt adhering to it. Heat \he solut1on to boiling-eoagulation~ Saturate 25 co.of serum wi th roagnes Lum sUlphate<>-~Serum glObUlin is preeipitated,serum Serum albumin and albumin glObulin remains give the in soj ut f.on , ~ommon proteid reactions. , , In the muscle we find a flui6,the muscle plasma~resl:tmblin!S the blood p08sma;\'(h.ich coagulates spontaneously ~separatillg a proteid, myosin and yielding a s er um-j'he plasma is rapidlY coagulated after death and is an important fac:tor 1i"l the c aus e t i on of rigor mortis. Dead mus oLe con t a Lns S l)\~era.lprot e ids, SOUle of Which ar e sol u-ble in water and ~alt sclution~a~d some insoluble4Myoalbumin, myosin .muscul1n,and myoglobulin belong to the first grouP7and the stroma auba t sn ce b eLong s to the La t t er '" • Mus<;le contains a complex Hlyco'~nucleo proteiu~MYO-·PHOSPHOCARNIO ACID, \Y'hi~h t s beleived to be the s our ee of en er g y in the muscle" The extract ive bodies of the muscle aloe ampor t ant ,and ar e both nitl·ogenous and non-nitrogenous"Creatintthe xanthin bases,urea and uric acid are found"They seem to be the result of ~rote1d wetabolism'iin the museleoln,osit,glycogen,suge.:;;> end lactic acid are non-« , nitrogenQus extraetives~onstantly·presentc> Inosit is prObably an aro~ati~ alcohol,but 1S often classed as a carbohydrate.Glycogen may be absent from dead muscle~being transformed. into dextrin and sugar post-mortemoLa~tic ~cid of th&. In~sclB id'sarcolaetic acid,darived from several sources- The XAN'I'HINR ~S~:S'so far isolated from the animal cell 81,~ TI in nUml:Hr.'I'hey are all rourid in the muscLe an d are •roris t an t p .. o duo t s of the cleavage of nualeins, (cell nueleins),They can be obtained by synthetic processes from uric acid,and an in~reased secratio~ 0f urIc acid follows their ingestion as food.Yhey are all descr~bed as s ucs t Ltut aon pro-mets of plJFDJ,the mo LecuLar' structure of v hich .is c nar eo t er as t t c of the gronp,and is known aa the pur an Due 1e us or r int5. 'l'he t' crmu la is given b elow :the nurno ers of t he members being a dte Ii for o onv en i en c e in des i~nfcl t inH t he subs tit u-· j / t ion , eompoun d s , , / 4C~~ I ':J ~ 2 q ~:: N y'S:11hin is known trioxypurin(2-,:-E),lS 8S 2-nHoxypurin,an\.) ShoVID co I the q ij C - its formulae; HN - 00 GO i ,.. H ,.., I :0 N -.... , . n . 2'.f ./ 8 C relation to ur r c ac a d \ cII - ~n'T_ .. C - by b N/ f.1i~ - Xanthin Pecogn{t10n pr ot eras of mus cIc , ~'!ix 100 grams or finely ..Uvided I ean beef ,iith :300 tP'ams uf water 8~d allow to I stand at room temperature for J hours. Pour the mixture on a linAn f~lter and prees the residue with the hand,snd of some of the filter the solution~ Test the reaction of the filtrate toward sensitive litmus paper, 8,r. d t owar d Lacmo r dv'r es t the reae t t on of a solution made from meat ttat has stood some time.rhe presence of mono and di calcIum ~hGS. pta t e anti the formation of sa r co La e t tc a c i d ,explains the p e cu I ia.r reaction of the solutions. Fractional Coa~ulation. Pour TO eG.of the filtrate into a test-· tUbe and place in a small beaker halt fUll of water.Heat the wate} i~ the beaker slowly ,at the same time holding a thermometer in t h e liquid in the test tUbe.Be.oreen 50 -51) Gea C02q',5ulation occurs Pilter and heat the filtrate to d5 C.-a sBcond ooa~ulation.Fllter aDd heat the Cilirateto 75 C. a third ~oag~lation occurs. ~xtrao,; the meat residue with a Ifi percent amrnon rum Chloride solutioD,adding enough of the latter to form a moderately thick peste. Coyer the vessel allow to stand 24 hours and filter. Pour a quantity or the filtrate into a. la:Li::l excess of water. e Myosin is precipitated. The precipItate is ,tissoJ.vea v/ith great by extremely dilute hyarochloric acid formind aCId albumin.On n)itutralizin~ the acid solut~on with SOdium hydroxide the adid albumin is precipitated and passes Into solution When an excess of' alkali has been added. , ' . Plaoe a fe~ drops of the filtrate U~ion a pieoe of rock salt.A film of myosin is deposited as the solution becom6s saturated \Yith salt. r~w Boil a filtrate from oxalat·".), co.of the flltrate.The myosin is ~oa~UI8tod and the the Coagulum contaIns ea Le rum, ('feat '-'nth 8.ll1mon~um ! "he constituents of b~ne are or~ani.,L:aloium ,and iron phOSPhate) And' organic (Qssl3in),1'he iTon ia yrobabl:v' derived In part,from the b Loou of b·'One.-Oasein .is a Collagen.anl1 on boilin~ iVith dilute said Jields gelatln~. rhe mineral matter can be removed,~ilhout alterincl the appearance of th3 bone;t:y allow',ing the non e to stand in con t ae t with dilUte hydrochloric acld for 2' hours.8y this treatment the Don. b,eeooes i-I iabl.e. of Gala till • or i~alatin 25 eC.of <l1stille,j 'Vatdr and alIa,," the end of this time t n e tSelatin is a.'Iol1en Eeact r Pour upon a I5 am t,o stand 24 hours.At dissolvet1.Decant 10n$ 8.(lJ 8 ~c.Of distilled "(star; the iSelatin IHssolveS;Fwa than Cool th~, gd~tinous mass t nus Obtained add about 50 cc s o r 1Vater;and heat a~ain 9Ver the Wat~r bath.1his solution of ~elatln after it but neat "0 no t over I.he water the 'Vater bat./'! until cooled,IS to be use4 for th~ follOWing tests. "011 a portion of the aolution after a1.ing to it a re_ drops of aeetic a~id-no preeipitats I~ formed. has Add to anotner ~ortlon aaatio aoid and potassi~ rerrooyanlde-no it from albumin and alt;umoses.). T~ stew c~.a~d mer~uri~ chloride solution-no preaipitate. Addition or tannin ,or hYdro.nlorl. aaid ona phoSPhotungsti. aoid give a voluminous preol~itate. l-:r'9~lpitate(Distj.nguishes 90il a portion ·,lh oao third lt8 vol~. of nitric aoiO-8 faani yellow ~olor t~ pr0JUced,ShO~ing the presenco of an aromatic / ra,1itJal. <'laustie soda &'1,1 a little copp er sUlphnte:Ji'Te e bll.~~ violet e oj.or without a t r a e e or red. (.Dist.in~uishes a t rr orn a Lcumos ea tl,nd p~~on~s. )By heatin~ to boilincl tif little copper sulphate 1$ aJded...,.th~ ,,,alor turns s omewhet )"c·,d;i.t' more I~OP?er ;sulpha.te is us e a , boilln!~ does not ;~hi~nefe the color. Bo11in~ with ~illons rea~ent produdes a faint pink or rad Jolor~ 'l'his reaction dis t in,>{11t sn es gelatin from tJTvt e-i.1::;ln benElral; ;0<1 sho~s the abs en c e of t he t yr os a n il,rOup. 'fhe addition or cr omm e wa t er p"O'.lUr-,:t'"S a heavy yellow precipi tat9,possesaln~ tou~h a~h~siY8 propertia&. n~~l~tine pos s e s s es the rlro~ert~· ot'hol<ting many tJrecipl.tates in s usp ens rcn in a r i ne Lt dlvided conJltivn,so that U'J.1 pass thr~ugh filter pe.~er;o:r of p,.~"an In~ rne (ormation or preJlpitates. 'l'HF: URTNF~. 'l'he urine is th·r~ most amp or t e.nt an rma I oxeretion.it. is t ne tn3e,ns of eli~in8ting tne nitrogenous waste material,as well as most of thewatHr and solUble nu ner aI sUbstflntH~8 •.~. stUd}' of thH ~omposit t on or tho. urine wlll g-i",e important imformation re~arJi"ng me t ao-« ol1sm,the naturA of the ¢h9rni~al pro~es3a8 takin~ place in thu body~and th~ condition of the urinary organs. In health and on a mt xe a ditH, the quan t i t y (if ur an e seer ete<t in i. acout THOO ceo t,~0nt8ininH 50-tj() ~;,ra.z.nsof soliJs tof /!:~j grams IS urea. "'hn r ea e.t Lon is D.cid or ampno t er a e , and the sp.g.about T020. :\lmost all the ni trogen of urine is searete.~ as ure~~.·l'he othf.lr nitro~enous ftonstituents are uria Rcidtxanthin bases,and araatinin tfhe constituents of urine are cla5GififH~ as follows. !.- Produ-::ts of norma.l IJetaboliS{J). :2. ?ro\1U(~ts of foo(! impurities. 3. SUhstances due to impurities in the fOOd.oot chan~eJ in the organism. ~. Products elabor~ted by the body as ~roteotlYes a~ainst drugs and fOOd impurities. 5. Produe ts seor6t ed bY' c,?r tain indi.viduals. (1 diosjrn ~ras y. ) • ~). 1\:8. ter,ials no t connee ted "lii th metabol iSInt but the rasul t of :6,4 lJours ;vhi~/"; :3:; to deo.~raposition 10 the intestine. 7. Pro~~~ts of disturbed metabolism. B. SUbstanoes ooeuring pathologically_ rhe followin~ table Sh0WS the constituents acaording as they result from the metabolism of urin8,8rranw~J of rood element. r"OOdS. Ij At:F.lON. Proteid. Nl'rRO(j~~N. ?HOR PHORUS. sUI,PHTJR. Proteid. Nuoleo-prot. Phosphates. Prot ai J. Phosphoric Slulphates. l?ci.1 iier i-v- Preformed a t rves . Oonjui:Sate• Carbohydrate. fi'a r, ff:xeretion. Carbon rli-oxide. ! UrEl8 Uri~ acid Hippuri~ aeid Creatinine Aromoni&. Xanthine bases. TNOROANTC II: UnoxidizeJ Sulphur. BAS~S. SOIJi urn, pot ass Lum, magries rum and c aLe ium oxides. The inorganic bases forme~ in metabolism,oceur in insufficient .quantity to saturate the acids ~re5ent.The excess of acid is taken up by ammonia prepared b.y the organism for this purpose. Wnene"ler 'the bOdy forms a protective sUbstance,it always ma.kes an excess of the material.The eXCHSS of aromonra r orme o in this case 1S como rneu WItt the carbon di-oxide formIng carbamic acid,(amido-carboni, 801e;); I~hi~h corne rnes wi th another molecule of a.mmonia forming anmon rum e ar eama to. This sal t is depr ived of one moLe cuj e of «at er in the liver,and converted into urea. Uric acid is formed in the liver ~robably bY the oonJugation of lactic a~id a.nd ammon La iw i t n urea. Hippuric acid occurs abundantly in the urine of herbivora,and in human urine after the ingestion or benzoic aCld·or any of its precursors. Creatinin is derived from creatin,of whi~h it 1$ the anhYdri~e. Creatin is present in the muscles ~t all times,and the excretion or ~ree t inin is d1reetl y aap en dan t on the amoun t - of muscle (meat) in the diet.'l'ha daily quantity of oreatinin is small on a mixed diet an o is no measure of rnus cuj ar- metabolism. ~he preformed Gulphates are alkaline salts of sulphuric acid. Conjugate sulphates are etherial combinations of the acid and eroma.tio alcohols. Class 2. Class 2. ~he ~entoses found in the are generally the result of food impuritY,but urine after lar~e doses of morphine. are Glynuronin a~i1 ocnurs ounJu~ated;uauallY after taking chloral or camphor. 'i'h,;:, acid occupies a position int.ermediate bet'·'/een the IDOno and di-basic acids obtained trom tn9 sugars.It uan be looked on as a dibasic acid one or whose carboxyl groups has been reduced to the aldehyde state.'l'he composition of glycuronic acid is 'COH(CROH)4COOH 80th the atove reduae dopper solutiofi and may be ~onfused with dextrose. Distinguishing tests will be ~iven later. (, I '/, II. Class 5.. GYS'l'T.N .is am t r-ogsn, ., _ some cases In large qua~: lus. Alkaptoni~ a~ids,re4uoe kno~n,-homogentisie a~id C6H3{OH)Z02H30HCOOR. Por tests to distinguish of su~arI in urine. aompoun d eon t a m ang sulphur. It tty and may ba Jeposited,forming o eeure in a calcu- r solution .. l'wo ofthe,se aei-1s are CtiH3 (OHJ;JCOOH. and ur-o Leu czna e acid, Penlings these acids tram dextrose,sse detaction \\. Class 6.. Nueleo-albumin,o,,~urs in the urine normallY,it is easily distin~uished from serum albumin. -As a result or putrafaction in the intestine there are excreted in th~ urina,inJlcal ,skatol,phenol,pyrocateanin,sulphuretted hydrogen,para-~resol. Gr ,3501, WhiCh is usually ex cr-et e c ,1ike the other aroma t i¢ al·JOhol in combination vrith potassium acid sUlphate,i~ methyl paroxypnenyl G'itl;OHGH3. lndol nitrQgenouM phenol deri9atives.rhey are formed by the decomposition of proteids. Indol is ./ CH~' in tne liver this if; oxidized into C6H4 ca. inr1Qxyl, /" COR ~ ~ NH /' C6H3" »: CH. --- 'i'he indoxyl is conjugated doxyl potassium sUlphate~ with potassium NH ./ acid sulphate, forming 10- Patholo~ically any of the normal constituents mny be increased, or 1iminished in quantity. Almost any constituent of the body can occur in the urine durinJ disease ~rocesses.Those of interest as aids to diae:nosis or o t her-wtss elinieally.are <1eserib,e<1 in the direetion~ for the exsminatiQn 6r 'urine. 1. General Reactions. 'Pest t h e r-eac t i on of fj"eSh ur-Lna also the r-eac tI on of urLne that has stood for some time- the former is usua I Ly acid and clear, the later alkaline and cloudy. With small quantities of filtered ur i ne make the followine; tests, 2. Add hydrochloric acid and heat- dark coloration of the urine, on standing possibly a deposition of uric acid. 3. Add caustic soda solutionprecipitation of phosphate, which on heating forms, into flakes and on s t and i ng eradua11:" settles t.o the bottom of the vesselThe precipitate rna:' or )'la:r not be colored. Cr~'stals of ammonde pos it ad whe n the so Lut ion is allowed Lum. magna Ul:'1 phosphate are usually to st and Boil a portion of the urineif the r-e ac ti on is acid, the urine remains clear; if neutral or alkaline, a precipitate of pho spha't e s usually occurs. Addition of a few drops of acetic acid dissolves this precipitate. 4. Add bar rum chloride solutiona white pr-e c Lpi t a t e cons Ls t Lng of bar-Lura sulphate, and bar1111'1pho sp hat e ; add i tLon of hydrochloric acid dissolves a part of the precipitate. 50 Add silver nitfate solutiona white precipitate of silver chloride and silver phosphate. The latter is dissolved by nitric acid. 6 Add basic lead acetate solutionThA voluMinous precipitate contains lead chloride, lead phosphate, lead sulphate, and the creater part of the colorinc mattRr of the urine. Filter; the filtrate is noarly co1orlosso Basic lead acetate is used in manv cases to de c o Lo r i ze ur-Lrie , 81 .-1 0 u. Preparat ion of Urea. Evaporate SOO ci c , of urine (fir'st over a f r-eo f Larne later over the wat e r-« bath) to the consiste~cy of a thill svrup, cool with ice water, and add about twice its volume of nitric ac I d ( 7>~~;;t) that has been be I Led unt i 1 c olorle ss and then cooled down to zer o , A'lLo» to stand a short tLme an d collect the crystals of urea nitrate, u s i rig a suction pUlllr perforated po r-ce Lai.n plate etc, and wash w i t h a little cold 'colorless n l trLc acid. Dissolve in as little hot vate r as possible and as tnt, so Luti on e;ently boils, add smaLL successivE:' portions of potassium l'f:r;'lcl.l1sanate until t he solution of urea nitrate is coLor-Les s , Al.Lo» so Luti on to cool and ciraw the :'jother liquor from the crystals 7lith the filter purrp , Press dry 0;1 a filter paper and weigh ap}!l~oxir;w,tel~'. Dissolve. t.he urea n i t r a t e in a small quan ti t y of hot water and add SODe what more than the 8Guivale~t quantity of powdered barhun carbonate. Exaporate to dryness on t ne wat er-eba'th , ex t rac t the powdered residue with a suall cuanti t v of bc i Li.ng abso Lut e alcohol and allow the ail.coho Li c solution to e(~o1.. R~cl"rstallize n·,.t': ria t e r-La I from hot alcChol Wind the Doltine point of the"product. Urea is the no s t i npo r-t ant n i t.r-ogeriou s c ons t i t ue nt of the urine representinG under nornal conditiollS, a~out 85~ of the total nitrogen elioinated by t he ki dne y s , Cherliea11y cons icier-ed it is t 1'16 arnide of carbonic ae id and ~s represented b:' the formula (C 0 IH 1-", ). It crystallizes from alcohol l.n large quadratic prisms, which P1eit 132°C is very s()ll1ble in \"later, less soluble in alcohol and insoluble in ether. g ltt? RBACTIONS 01;1 UREA .. 1. Heat carefully a small portion of urea in a dry test-tube the urea melts and a' sublimate of ammonittm carbonate is ft~xx formed (strong odor of ammonia). 'Continue the heating until the melted mass begins to solidify. Af'tercoolinc dissolve the residue in' wat er (addine; a little caustic soda) and make the ~:~~~x biuret test .. The following reaction takes place when urea is heated as above. (Biuret) (, 2 cot , N H 2'2 = (C ° '2 N H (~ H2 )2 ~ N H3 a portion of Urea in a dr~T test-tube until the whole mass becomes solido After/cooling dissolve in water (adding a little caustic soda) and then acidulate with hydrochloric acid" - a precipitate of cyanuric acJ.d.. 20 Heat 3 C 0 (N H B) 2'::;' C~ H3°3 N3 +- 3 N H:3 (cyanuric acid) / 30 fo a small portion of a solution of urea in water add mercuric nitrate- a white precipitate is f'o rme d the ccmpo sIt t on of which depe~-~~ the concentration and relative quant Lt Le s of the two solutions used. When /Jhe,solutions are neutral and dilute;,> a salt is formed havine a composi-- tion represented by the formula ( IT H2 )2e 0 He (N 03 )2 • 3 BeO• 1'2, This is the salt formed in the reaction on which Liabie's volumetric method for the determination of urea is based" 4. Dissolve a few crystals of urea on a wa.tch glass in a few drops of water and add a concentrated solution (If oxalic acid~ precipitate of urea cxa.Lat.e , / (C 0 Hz H4 )2 CzHz04 H:P /. + Examine 5 .. Repeat (4) but use nitric acid instead of oxalic acid:. Urea nit-rate Examine mic:coscopically 0 is l'0 rme d ( CON 2 H4 o' If N 03 ) 6 .. Heat a small portion of' urea p C o 'H2 ., ·'4' +2 w i.t h r.r ·'2 c au st Lc soda solution .. 0 e C 0 2 ~'~" 2'" l'T H 3"T,L N2 ° • 7. To a small drop of norcury add nitric acid warm the acid and add a little urea- a mixture of Co! and No is eiven off~ ... .. 8 0 To a little bromine ro>, ..;Z 0 'R' water Ln a test ..-t ube add caustic ( NaO··,Iir) To t h I s solution Sodium hypobromite is for58d of ur-e a , .,I,?, T\T l. 2 . .~ . C 0 N2 H4 4 3 Na 0 3r ~ o r: oJ 0 j, 1 r) H .." ...~ 0 ,.l ..,... 0' soda solut'i:-onadd a solution 3 Ua Br. Prepara.tion of Urj.G~,·Acid.., To IOoCfCoco of urine add IOcr':'.:; Co of hydr-o ch l.or Lc acid and allow to stand in a cool place for 24 hours Collect the tSJlt}rt'tk"kx crystals of highly COlored uric acid and wash with water-· (Examine nicroscopically). Ill" 0 0 Suspend the crystals in a sma'l L quarrt Lt y of wat e r , heat, add enough c aus't I c soda to dissolve the uric acid and then decolorize by boiling "Kith animal charcoal. Filter, make acid with hydrochloric acid, heat to boiling and allow to 0001- Uric acid ~ obtained in this way is a colorless crystalline powdor- Collect on filter paper, wash'with water and allow to dry. Uric acid is very insoluble in cold water (1: 15000), insoluble in aID cohol and ether, solublH in caustic alkalies; in ammonia it is scarcely soluble. • REACTIONS OF URIC-ACID. 1. Hurexide testSee "Exaru nat.Lcn ' of Urinar:r Calculi". and 2 •. Schiff's reac t ion Dis solve a 1 it t Le ur-Lc ac id in s od Ium carbonate Place a drop of thin snlution on Filter paper previously moistened with nitrate of Silve 1'",. The s i Lve r nitrate is reduced to silver and a stain is formed.' , 3. Boil n solution of urI o ac id in Call s t ic soda w i th a small amount of . Fehlings fluidreduction wit& production of~a frey reddish precipitate. If the cor/per salt is in -exc e s s , t he Latt e r is ohtatnc d , It is obvious from this reacti~ll that some care must be exercised in ~akine reduction tests for suear in the urine. 4. To a s od i um c ar bonate so Lu" ion of u r I c acid add mage n s La mixture (Mg S04 or ITg c12" N H4 Cl ~ N Eo ... H20), and then silver nitrate so ... 7 lution. Uric acid is precipi.tated. as a celatinous maenesiosilver salt. Reaction (1) is ir.:J.portant for the recognition of uric acid reaction (4) for its isolation. Uric acid is cot a Lways deposited on adding hydrochloric acid to the ur Lne : in such a case it is ne ce s sar y to use reaction (4) in order to show the presence of ur i c acid. This test is also used for the quantitative deterMination of uric acid. IV. Preparation of Hippuric Acid. To 300 c. c. of horse s urine a dd a sl iGllt e xc e s s of mi lk of lime, warm , filter, evaporate the filtrate to a snall bulk and treat when cold, with hYdrochloric acid in slieht excess, The hydr ochf.o r t c acid decomposes the hippurate of calcium Lt ber at Lng hi ppu r Le acid which separates at once in the for.m of needles (usua:U.:i hiGhl:' colored). Collect at the crystals on a perforated porcelain plate (usinC the suction PUMp.) diSSOlve in hot water (to whi ch a lit tIe ammcn i a has be e n added) and deo oLor i ze wi th animal «.ant charcoal. :"i1 tel' while hot , evaporate, the filtrate to a small volume and whe'n cold add hydr-o ch'Lor i.c ac id- Collect the c r-y s t a Ls wash with a Ii ttLe wat er and r-ecr yat.a.I Li ze fr-o m hot wat er (Examine microsaopioeJ.ly). Hippuric acid, (C 11 C0 C H !i S COOE.) is nonobasic and forms salts whi(;J::I. 2 6 5 « are CGld for the most part soluble in water, It is soluble with difficulty in wat.e r readily in hot vat.e r , Lns oLubLe in ether. Helt.ing point 100°C. REACTIONS OF ~IPPURIC ACI~. 1. Heat gently a sma.l.'Lportion of t h e ac id in a clay in a dry test-tubethe acid melts, and solidifies aeain OD cooline. Heat atain nore strong~ the melted acid turns red, Give.s a 8ublinate of ben7.oic acid and an odor simi.l.ar to that of oil of bitter a Lmond s , du e probably to herrzo Lon i.t r LLe and hydrocyanic acid. The red ooLor is d118 to the decomposition of ~' o.o.e8l.l ( C H (N H 2) C (\ o H) The sublimate of benzoic acid has a .. 2 very characteristic microscopic appearance, is roluble i11 sodium carbonate ..and. is reprecipitated from this solution by hydrochloric acid. v. Recognition of Oxalic Acid. 'To 500 e ,c , of urine add a few Co 0 e of calcium chloride solution,make alkaline with ammoni a , acidulate faintly w i t h acetic acid and a.llow: to stand 24 hours. (Add a few CoCo of an alcoholic solution of th~nnol) •. At the end of this time filter t.nr ough a smaI L filter, wash with a little water, pLae e the filter paper in dilute hydrochloric acid, warm gently and filter. Evaporate the filtrate to a small volmne, make alkaline while still warm with N H3 acidify with acetic acid and allow to stand for a few hours in a warm placeD Examine the precipitate microscopically. VI. Recognition of Creatinine" Make 200-300 c ,c . of urine faintly aLkaLi.ne with milk of lime, .and add calcium chlor:i.de solution unt i I all the phosphates are precipitated-· Filter, trash w'ith wat.er and evaporate the fj,J. trate ... wash water (3fter faintly acidifyine with acetic acid) to the consistency of a syrup. To the warm syrup add XXX 50 coco of alcohol, transfer to a small'beak'eT, cover' with a elass plate and aJ.10','1to s tand in R cold place at least eight hours. Filter through aSI,mll fi Iter, wash w i th alcohol, evaporate the f U"traie to 50-60 c "c allow to cooL, Add 1/2 c ..c.' of alcoholic zn 012 cove r t.ho hreaker \v1th a class sclut ion (81' g. 1.20), st t r thorouchl~r, plate and allow to stand. ~2-3 days in a cool placeCollect the crystals of creatinine zinc chloride and wash them with a little alcohol. 1. Weylis ReactionPowder a portion of the salt, boil with a little water, allo'N to cool and filterTo the filtrate add a few drops of sodium nitropmissiate a~1a-:ke-alkaline w i t h caus t Le soda- deep red colo~tion which quLck Ly fades to a s t raw co Io r , Act d if'v with acetic acid and boilPrussian blu~ or berliY' Greeno This test can~ also be made directly with the urine, but since' acetone gives a similar reaction, it is necessary to boil the urine and cool before app Ly i.ng the test. Jaffis Reactiollo To a portion of u.r i ne add aqneol1s solution of picric acid and make alkali~e with caustic soda- a deep red color •. Acetone yields no such red color with this reagent. 961 0 VII Phenol(a) Sulphate Phenol, of Potassiun .. (e H 6 5 Reactions of Phenol. Prepare a 2~ solution and a 0.2;; so Inti on of pheno L and make the follCll'ing tests with each solution. 1. Add ferric chloridea clecjp amsth:rst color 'which is dischare;ed by···. strong ac:i,.cis- Hany phenol derivatives (salicylicacid - orthohy~C acid) give a z:m:kkxxsimilar reaction .. 2. Add a t ew drops of TIillon's reacent. and heat to boiline; -intense dark red solution or red precipitate .. This reaction will.show 1 part of phenol in 60,000 parts of wat er ; the color however in such dilution is pink. This reaction is also e;iYen by all rhenols. 3. Add bromine water- A precipitate of 1'10nob;r'OYlD phenol and .diGrOmphenol is formed, which is characterized by its pen8tratine; odor. Further addition of bromine produces a yellowish ~hite crystalline precipitate of tribromphenol (C6H;2Br'7pJ-I) e Reactions (2) and(3) are the most delicate and the ones generallY used- Reaction (3) is also used for t he quantitative determination of·" -.. ,........ phenol but certain precipitations are necessary to avoid the formation of bromoxytribrombenzene I C H Dr 0 Br,Z: tetrabromphenol) After the us~of' ..phenol, this substance m§.~T2be 3fOlmd as such in the urine. Hor se ur me and pathological urine usually contain para-cresol in place of phenol. m-n / / ~ The reactions of para-cresol are similar to those of phena1, though Les s pronounced.. The add it ion of ferric chloride gives a dirt.~7-grey ... co10r- (b) Phenol sulphate of potassium (C H 0 S03K). 6 5 Reco nition of Phenol in Urine .. Phenol and cresol are foun inurine In te form of etherial sUlphateso To prove the presence of phenol it is necessary to first decompose by heating with h~rdrochloric acid. Malee 500 c .c , of urine alkaline with Ua2 Co3and evaporate almost to dryness on the water-bath.. Add 100 c.c. of sulphuric acid and distil. Makes tests for Phe~ with the distillateo "yIII" Pyrocate~nC This substance occurs in human urine as a conjugat e sulphate and caus~s alkaline urines to turn dark on exposure to the air.. It readily reduces solutions of metallic salts, a fact to be taken into consideration when dealine with the presence or absence of suear in the ur t ne , Prepare. a 0.2;( aqneous so Lut I on and make the following tests," 10 Add dilute ferric chloride solutiongreen color. The additidn of a little tartaric acid and then a.smorua changes the creen color to cioleto Acidulating with acetic acid produces the green color again. 2 Add a Ii t t Le armon i a and then a fev! drop'S of silver nitrate solution-immediate reduction to l1etallic s i Lver 3 Addition of caustic soda colors solution e;:reen, br-own and black. 4. Addi tion of lead asetate prec ipi tat es p~rl'ocatechin as a lead comPOund. The filtrate from this precipitate does not eive any of the re~ctions aboveo ' 0 ;» 0 IX ~eni tion of Judican_. 1. Jaffes methode To 5 c ;c , of urine add an equa.l volume of concen ... l'rated I-1" ce and ru x thorollghl~'" Add drop by drop a n soluti on of bleaching pov!der un t il the maximumof color is at tained and s riake gently with 1 CC of chloroform. The chloroform is colored blue", It is difficult to e s t i.mat.s the quant Lt y of hypochlorit'e ne ce s sa r-y to pro~. duce the most intnnse blue and an excess of' the reagent oxidizes indigobluea The reaction ix in any case takes place slOWly and does' not always ShOT,r" the presence of indican unl e s.s great care is taken" Hlgtlky colored t'cd;;rwc:rx urine should be decolorized w i t h basic lead acetate before making the test and any albumin present should be also r emcve d , 0 Gbermayers r';Iethodo l'ii"Orin excess) and filter 4Q To a port ion of urine t hr ough a dr? f' d Lt.e r-, add lead acetate To a portion of the filtrate add an e-qua'l,colume of' concentrated H cl ; which contains' O~2-0.41 of ferric chloride. - Shake the so Lut ion. with chloroform." ,.Ferrj,c chloride does not oxidize indiGo blue .. 3. Mac I:unn t s !!ethod. Boil equal volumes of urine and' concentrated hydrochloric acid that contains a trace of nitric acid. Cool and agitate with chloroform. The chloroform is generally colored v i oLet , and shows two absorption bands near D- one dtle to indigo- blue, the other to indigo red~ X Recognition of Unoxidized Sulphur. Pour upon a small piece of zinc a little hydrochloric acid and allow the acid to act a short time. Pour the acid off and wash the zin~ with water. Place the piece of zinc in a flask with 50 ocxfrcCo of urine and add enough hydrochloric acid to cause a gentle evolution ofhydrogen. Suspend in or over the neck of the flask a piece of filter paper noistened with lead acetate solution. The paper turns blacko Only the so called neutral s:tqi{ sulphur of the urine eives 428 with nassenthydrogen. XI. R~cognition of Pepsin. Agitate 200 co. of nrine with a shred of fibrin b:T drawing air through the urine .~fter an hour or two' r-emove the fibrin and wash with water. Pl~e t.he fibrin in a test-tube with a little h;Trdochloric acid (0.2~) and alloW to stand at 400·tmtil the fibrin is decomposed~ Wi th the soLut ion make the biuret test. Repe at the experiment with boiled urine. XII. Inorganic Constituents. 1. Chlorides _ Acidulate a few co of t be ur t ne with nitric ac Ld and Add silver nitrate. A white precipitate of silver chlorideo 2. Sulphates- Acidulate a portion of the urine with hydrochloric acid and add Ba cL. - a cloud of barium sulphate. " 3. Etherial sftlphates Nix 20 co. of urine with 20 cc of' an alkaline 2 solution of barium chloride and filter~Boil the filtrate with 1/ its volume of concentrated h:rdrochlori o acid cloudiness due to the precipi tat,ion of barium sulphate. (norniallY very little) (Do not use too much Hel). 4. Phosphates _ l':ake 50 cc , of urine a'Lkal.Lne w l t h anmond a , and filte":~ Dissolve the predipitate in nitric acid and test t h- solution for phosphoric acid w i th moLy bdLc solution, make the filtrate acid -wi t h nitric acid and test for phoaphor Lc acid with mol:rbdic sol'lJt.ion .. ,The phosphoric acid in the filtrate represents the excess of phos~ pnor t c acid over that required for the calcium and flagnesj,um 0 Q XII Albumin. The followine tests should be nade with normal ur Lne and with several sp02cimens of vathological urine. All material should be. perfectly cleaT and if this cannot be effect »d by filtering t nro ugh paper, f il tel' ., through asbe stos or ag i tate the ur tne with magnes.ta (1<'15 0) and filter 1. The Boilin£.? Test. Heat a portion of the urine to boilins in a test-tube and whether a precipitate has been formed or not , add concentrated acid (nitric) drop at a time until the volume of nitric acid used is about 1/20-1/10 the volume of t he urine. In case a flocculen.t precipitate is produced the presence of alhumin may be considered pro-ven', Not. 1. As a positive test for albumin this reaction has great value, but a negative r-esu.l.t. is no indication that albumin is about: ..Note 2. Faintly alkaline or amphotern urines may yield on boiling a precipit~te of phosphates which is indistinguishable in its gener~l apvearance from a precipitate of coaeulated albumin; and an al~aline uJ"1ne may rama in clear after boiling even t hough it contains Ej.lb'l.1min. 0 No.7. The subsequent addition of nitric phosphates aftd precipitate proteid acid. will dissolve which remains in 'boiling. No.3. If an acid urine yeilds acid, albumin is absent and there no precipitate is no necessity . precipitated llt solution after on boiling and remains for the additon of nitric' Note 4. acid. When the quarrt I t y of albumin is snaIl, the addition of a drop of nitric acid to the boiled urine produces a precipitate which disappears on shaking (xx the fluid. When the urine is rich enough in salts or when sufficient acid has been added to render the medium J incapable of holding acid albunin in solution, a permanent preeipitate is produced. upon this llrinciple is based the following very sensitive te st. Treat the urine with enol1gh acetic ao id to p r-oduc e a marked ac id reaction. (2-3drops of acid for 2OCc. of urine), add 1/6 of its volume of a saturated s oLut ion Of/odium chloride and boil. Under these conditions no precipitaj;/i;on of phosphates can. occur, and e"lren a trace of albumin \/ill be c.<mVerted into ac id albtunin and sal~ed out by sodium chlorides. Note 5. When this test. is properly executed there is no danger of confusinc albumin with uncles albumin or albmI1O$e, for both- of these substances remain in the IllX nitric solntion wh i Le it is hot. The same also holds true for ur t c ac id and ur at e s , but in case of concentrated urine it is we Ll., to dilnte a port ion of the ur t ne before making the te st e spec irilly if the prec ipi tate for-ned b;' the concentrated urine is grant1lar. A pr-e c ill it ate produced by the pr i gmerrt of Le teric urine will consist of biliverdin and will diesolve in alcohol. !Tote 6. Aftor the L,.t e r na.L or external admini fit ration of snch drtl[;S em as 'tl'upentine, toblJ-balsaM,cubcbo, storax, oil of sandal wood petrol etc. the urine may contain resino which conduct themselves like albumin as far as this test is concerned. These resins, howver, easily pass into solution uron the addition of alcohol. Note 7 In case the test y i eLds a sufficient quanitty of precipitate to rilter and wash, the material should be subMitted to the biuret 0 r-e ac t Lon , 2 Heller's Test. Place ahout 25 cc. of clear urine in a tes~-tube 0 (better a conical slass) and introduce 10 cc. of concentrated nitric ac id b:r means of a pil'otte who se point reaches the bot tom of the vessel The ni tiic should be allov/ed to flow ve r y slowly so that the lizuids do not mrx , but form a sharp zone of contact. Under these conditions albumin wi 11 be chanced to acid albumin whic h be ing ,.insoluble in ni tri" ac Ld ap pe ar s as a wh i te r ins in the 7.0n& of contact; on at anding the ring of acid albumin will Benerally becomes wider ext.ending upward int;o the urine. Note 1. While this reac~ion is extremely sensitive it has not cethe disadvantage e ornmo n to so Dan:, albmnin tests of show ing the' prese.n of traces of pr-ot e id "''lhich are nor-ma'l Ly present in avery urine. Note. 2. In oa se s where the urine is concentrated or where there is e xc e s s I V(~ quan t i t~T of uric ac id a e Loudy zone may appear on standing This zone noweve r is always considerably hieher than the zone of con-' tact of the two liquids, and will dissolve when the urine in which it is formed is carei'ull;' removed from the nitric acid and warmed. No.. 80 Urines which contain as r~tch as 45 grains or urea' to the liter may deposit a crystalline precipitate of urea nitrateo So concentrated a ::artm:x urine shou.ld be diluted before the albumin test is applied .. Note 30 As in the boiling test a cloud for~ed by nitric acid may '6e referable to unclaoalbumin, albumose or urin acids.. The exclusive of these substances can be accomplished by the methods giveno Note 4 The' colored ~x rings which are produced have nothing to ao wIt~bumino A ring which varies from rose to brick red is due to the normal pigments of t he urine, a mahogany ring .Ind.Lc at e s Lnob i Ld.n; while an excess of urinary indican produaew a blue ring which may be so intense as to color the entire solution after the liquids have been mixed .. 3 The Potassium ferro e anide te st. 00 idify' a small port ion of urine and add a fev{ drops of p t as s Ium. ferroc~ranide. A clouding shows the pr-e senc e of albumos of al imdn provided that the precipitate is not soluble on heating' and that addition of acetic acid alone did not produce a precipitateo 4 Trichloracetic acid Test: By means of a pipette place 1 or 2 CC::-of an aqueous soltl,tion of the reagent (5p g - lQ147) in the bottom of av t e st ...tube co ntaining a few c c. of filtered urine as in Heller! s testo A white ring will be seen at the zone of contact between'the two fluids its intensity uarying with the amount of albumin present .. The colored rings whd c h are formed when nitric acid is 'Used are rae-ely o bse rved , Serum albumin ser-um g Lo bu'l In and albumoses are precipitated, the presence of the latter being recognized by the fact' that the precipitate dissappears on boiling and reappear on cooling.. This test is undoub t e d.ty one of the most sensitive, and b:r its use it is possible to demonstrate albumin in urines with which the more COmMon tests yield negative resultso 0 0 0' XIV..., Recognition of A'Lbumo se s , ~esFthe 11ri1J.8-foral bumt n ~ -;"i"""'f--="i-::-t--:"i-s pre sent ac idify st r-ong l y with acetic acid~ add an equal amount of saturated sodium chloride solution, beD. and filter = On cooling a.Ibumo se s will produce a cloud wh i ch disappears on he at Lng and r-e appear on c ooLtng , make the filtrate al·kaJ.ine with caustic soda 'and add copper su Lphat e, (Biuret reaction) 0 .Use 0" 3 grains of albumose to 100 c c. of ur-Lne , XVQ DextroS9G, following tests should be made with each of four solutions t2;zzz (a) A 2f solution of crape sug ar in wate r , (b) A 02% so Lut ion of grape sugar in water ... (c) a 2~ solution of grape sugar in normal ur-Lns {d} a 02% solut ion of crap'e sugar in normal urine A number of patb.o:Logical ur i ne s should then be examined, but must be free from pT'oteid.s before the tests are applied .. 10 Reduction Testso These tests all depend upon the power possessed bY-grape sugar to reduce various substances wh i ch eive evi.dence of this reduction by the formation of precipitates or by changes in color" As normal urines and moines which are sevreted after the administration Of' certain drugs o onat In sub s t anoe s which are reducing agents" It is clear these reduction tests are not to be re~arded as conclusive of the prasaQ~e of sugaro ------The 0 �A) Trommers Test. The urine is made strongly alkaline with sodium ~Ydroxlde and a 5% so ution of copper sulphate is added at a time until the precipitated coppe hydrate no longer dissolves on shaking. The liquid is then heated to he boiling point but should not be allowed to boil. If sugar is present yellow cloud of cuprous hydroxide will be found which may gradually change to red cuprous oxide. When the precipitate first Dk~kes its appearance the heating should be discontinued as the reduction will proceed rapidly and the reducing action of other substances is eliminated by avoiding the boiling temperature. This test has the disadvantage that an alkaline copper solution is reduced by many substances which «Ia~XA occur in normal or pathological urine or which may appe~r in t.he same urine after the ingestion of various drugs. f)uch substances are uric acid, creatine, creatinine, allantoin, mucin, pyrocatehin, hydroquinone, me e;lynronicacid com--pounds, the alcaptonic aeids (homogentisic acid, urolanci~c acid), urobilin gall pigments, moreover, after the inCAstion of certain drugs anyone of a large number of these reduoing substances may appear in the urine (b) With Fehling~s solution- When Trommer's Test is carelessly executed an excess of copper over that required for a small amount of sugar will be (\'onvertedinto black cupric oxide which may mask a small quantity of cuprous oxide. This may be avoided by using mixed Fehling' flUid, when any excess of copper over that which is required for the reducing substances will remain in solution. All of the substances which interfere with Trommer's Test must be noted also here. (c) Bottger's Test A port.ion of urine is made alkaline with caustic soda, a little bismuth nitrate is added and the solution is boiled for several minutes. The presence! of sugar' is shown by the appearance of a black precipitate of bismuth or m bismuth suboxide, or by the darkening of the undissolved biSMuth salt. This test has the advantage that bLsmubh salts are not reduced by many substances which wasil~r reduce an alkaline copper solution- uric acid, pyrocatechin, hydro quinone , creatinine and alcaptonic acids. ' (d) Hylander's Test To ten volumes of urine add'one volume of MYlander's reagent and boil the mixture for [-) ninutes. The presence of sugar- is shown by the eppearance of a black precipitate. Hylander's solut ion is a pr-epar-at ion contatm ng bismuth, which is extremely sensitive to the reducing aetion of sugar. The test has shown the pr-e sence of reduc Lng substances in norma l. urine. 2 Phenylhydrazin Test. To 100 cc. of a urine add 2.5 grains of phen~71hydrazin hydrochloride and 5 grams of sodium acetate: heat 3/4 hours over the water bath and filter while hot- On coolting yellow needles of phenYeelucoOazone are depo s t ted. When t his substance is pure it melts at ~~~x 2040 - 2050 3 The Fermentation Test. Shake a portion of the suspected urine with some compressed yeast and fill into a fermentation tube. Allow tv tuand in a warm place, preferably in a thermostat which is kept at 400anclnote the collection of eas bubbles in the upper part of t"oo tube. A check test should also be made with a one per cent solution of dextrose which has been sh~ken ffitha portion of the same specimen of yeast. It is also weL'lto make a second check test with water that has been shaken with the yeast. The fermentation in each ease should proceed for twelve hours. 4 Polariscopic Test. Before applying this test it is nece saar-ytQ, renove all proteide from the urine and to free from a greater part of the coloring by prec1pitatine with a little neutral lead acetate. Read the zer s of the tnstrument , insert the t ube which has been previously filled with prepared urine and turn the polarizer unt LL extinction is obtained. The sensitiveness of the test depends entirely upon the construction of the instrument and as r10st instruments are not capable of showing a trace of sugar it is generally useless to try the test when no positive reaction has been obtained w~th reduction tests. 0 0 10. THE FOL:LOWING TABLE WIIJ' .. SHOW THE TESTS NECESSARY FOR DISTINGUISHING SUGAR, FROU OTHER REDUCING AGEN'l'S,OCCURRING • •• Substance • • • " •••••••• • .. • • • • • • • " •••.•••••••• • • • Fehling's Test .. • • • • • • .. • • • • • • • • • • .. 41 IN THE URDTE • •••••••••• -. •••••••• t. Bismuth . Fermenting tl Phenylhydr-az i ng Dextrose Reduction Reduction Ferments Osazone Dextrorotatory Pentoses Reduction Reduction Negative Osazone Dextrorotatory Glycm"ollic Acid Reduction Reduotion Negative Osazone aevo-roratory in urine '1' Alkapton! Acids Rednction Negative Negative Negative Inactive Lactose Reduction Reduction Negative Osazone Dextrorotatory Uric Acid Reduction -Negati va Negat ive Negative Inactive Creatinin Reduction Negative Negat ive Negative Inactive Pyrocatephin Reduction Negat ive Negat ive Negat i ve Inactive. . 1: 11. xs , Reccgn LtLon of Aceto Acetic The test must bs made with fresh AC1CL l~,3H C O. C H2 COOR} urine. 1. Tc a few e ;e , of ur-Ln« add ferric e hl.or-Lde solution. Should a precipitation of phosII: ate occur this Xci: is f Utered off and mor-e of the. iron solution is added to the filtrate. A Bordeaux red color indicat .:e s the presence of acete acetic acid. • 2. Acidulate a port ion of ur t ne (10-50 c o, ) wit.h dI Lut e sulphuric ac id and extract with an equal colmne of' ether. separate the atherial extract and shake it w i t h a little Vt1ry di Lut,e fl~rric chloride solutionthe presence of aceto aeetic acid colors the aqneous solution red. X"ITI Recognition of AcetonQ/(rH3 ) ~ C (l/ Diabet io Urine) ,- Aci tone is a colorless liquid havtng an agreeable odor. It is sol- 0 uble in alcohol, water, and ether in all proportions. BoilinG po~nt 58 To 250 of normal urine add 5 drops of acetone and an equal anount of hydrochloric acid; submit the material to distillation and uS'S the first portions of the dlstillate for the followine tests:Iodoform Test.A few c c. of the distillate are t:r-eated .r i th s evera arops 0 a (llllte s()lut ion of iodo-potassic iodide and caustic soda- prec ipi t at ion of iodoform ( eEl ) on warru ng which may be readily r-ecognLzed by it s odor. 2. R€~rnold' S Test Treat a few cc , of the di.stillate with a snaL'L amount of fresh!:' p r-e c ipitated :rel10\, oxide of mercury. This is prepared by p.cv.EKcd~'c{::::o= prec ip i tat Lng a soIut ton of mar-cur Lc chloride (poisonous) wt t.h an alcoholic soLurLcn of caustic soda. If acetone be pnesent a black color will result in tho clear filtrate upon the addi ~i on of a few drops of ammcn i um su Lphd de , XVIII Recognition of Bile Piements (Ioteric Urine) 1'. Gmelinr s Test (See Biliar~r calculi). 2 Gmelin's Test (";odified by Rosenbach- Filter a Cltlantity of urine through filter paper; r.hen br Ing a drop of ~re1low nitric acid in con.... tact with the appr-oxi.ma t e Ly dry paper. 3 .. Make a portion of the urine alkaline with sodium carbonate solution (1-2 drops) then add calcium chloride solution until the fluid over the precipitate formed after ahak Lng is colorless or has the color of normal urine. Pilter wash the precipdtate, place in a test-tube wi th alcohol and br me rnt o soLut ion by the arlo,it,ion of hydrochloric ac ide Boil t h e clear soLut ion- e;:ceen and. blue c olol's. Allow' to cool and add nitrie acid- the sreen soLutt on turns hltiEJ,violet. and red .. This test is often positive when (1) is negative and is recommended when the urine contains a lare;e ar~;)'l!1t of indican. 4. Acidulate a por-tLon of t hs ur:tne with acetic acid and shake with chloroform. The lat tel' is colored yellow. 0 ~~II - Recoenition of Blood Piements. A xy aemo 0 1n- Tie aemoe;lobin. 1. 'Heller's Test. ".a e a por lon OJ t .. l.'l urine alkaline with caustic soda, and boil. A precipitate o~ hasic phosphates is formed which, if blood coloring matter is present is colored l'ed- at t ilnes when the urine contains a laree aMotmt of colol'inb nattar (bile pie;ment- etc.) .. It may be difficult to appreciate ths color of the precipitate. In this case filter off and dissolve in acetic acid, when if clood pi~ent be present the solnt ion becon-us red, and the color vanishes gradually upon exposure to the air. No. 12. 2. 8uaiacum Test.A mixture of tincture of' enaiaet.un and ozonized oil of turpentine is allowed to floVl carefully down the ?ide of a test tube upon the urine in such a manner as to form a distinct layer above the lTrine- a ';{hit~ ring which grad1.lally turns to blue 'ilill be seen to form at the surface of contact. I: 3 To about 100 c c , of sus ec t ad urine add a small quantity of a solution of eee' a Lbumfn in vat e r , Heat to boiling and, filter the c oneulated a Lbumf.n, This coagulum will contain haema t In , Grind the precipitate in a mortar with about 200c. of absolute alcohol and a few drops of concfJntrated sui\phuric ac id transfer to a flask, heat to boiling and filter. After t h e filtrate has cooled make alkaline with canst ic soda. Raduc tl w'i th ammonfnum sulphide, and e xamf.ne spec tros- copical1 haemochromogen. examination. (B) HAE;TATOPORPHYRPT. A direct speetroescopic examillatio11 the urine for t h t s pigment is generally Hnsatisfactor~r for t he reason that r.he field is USUally obscured by the presence of the nther colored snbstances in. the urine. It is therefore advisable to isolate the p i gmen t b:r some pro-etlss of' preci~itation of extraction. 1. !lethod 01' (Tarrod. Treat 100cc. of suspected urine with alkaline bariun chloride so lut; ion un t i 1 the r eage nt no J.onger fo~ms a pl>ecipi tate Haematoporph~Trin under t he se conditions is p:cecil'itated L:. SC~6 f'o rm of chemical combination with the phosphates of the alkaline earths. Filter throlle;1tl a sma Ll. filter paper, was the pr-e c I p t t at.s once w t t h water and O:1.C8wit h absolute alcohol. P1ac e a wat ch c r-y.s t a I over the funnel and a Ll ow t he alcohol to drain off as c ompLe t e Ly as possible. Bring the mo s t precj.pHate. Lito a s:1<:'J.J.l mor t ar-, ack a bou t ten drops of h~'droch1oric ac t d- ~E1Cl E:~!011Gh alcohol to form a t h i.e k paste. ,liter crinding the paste, tra:. sf'e i- to an Es Lenmeye i- f'La sk , UP ing a sT1al1 amount, of absolute alcohol for "lashing, a m warm the rnaterial on a lIater-bath A110'."to become perfectl:' cool a nd filter. The filtrate is now examined spectroscopica1).y. If haemat opo r-phyr-Ln t s present the vent c h '"racteristic ab s or-p t ion spectrum of the suhs t.anc e in acid so Lut ion ":lill be seen •. 4. Direct for spectroscopic or E.iCAI'TINATr ON OT' URINARY CALCULI,. He.at a snaIl quantity of t h8 f inol~T liOYldered stone of a platinum foil: if the powder burns cor1111\~te1y 1t~avinc but little ash, it !.'1a:' contain uric ac id, ffi1lnOn inm.'1 In'atl'l, e:ist in, 01' xanthine: if i~, burns incomPletely 1ea~Tinc cC:lsiclerab1e ash, it 218.:' cO;'1trd.n 111'ic acid, urates, calcium, phosl~hate', macnesim'1 phOf~phatf!, HlnCnintlr1 nae;nesim:1 phospahte, or ea1ciuD oxalate. The i/lethocl to be IJl1Y'Sllecl in 1:he a:'tal:rsis depends ul,on this dif'f'erence. 1. The POI/dar burns complete1:, or 1eaves a mere trace of residue. Digest a ~'ort ion of th:e-'lIY\i-IClei~-::'li th di1nt8 h?di~ochloric ae id ',varming gently. Ca) It diSSOlves cOJ11pldtel:r -c:'stin oX' xanthine. To tflst for cyst in heat u. ]. ].1't1El of t:h,.::; l,o',,'der 'dth 8.l'lrrlOnia and f'il ter- pour the filtrate On a watch-Blass and allow to evaporate. Exanine microSCOpicallyCystin crystallizes in sioc-aided plates. Cystin stones are genera11:'81'1a11, havfj H ~Tol1oH colo)' and SMooth surface. No" 13 0 To t8st for xanthinfl make the' xanthin test with nitric acid and caustic sada(see chapter on muscle). Filter and wash the residue with water. (b) It dissolves ~ncoMp18tely~ Residue, Uric acid. To t e s t for uric acid make the murexide testPlace a smaf.L quantity of the re s rdue Ln a po r-ce Lai n dish, pour upon it a f'ew drops of strong nitric acid and evaporate over the 'vater-bath to dr yna s a- a yelle"Nish or reddish residue resultsAllow to cool and moisten with a little ammonI a- a reddish pnr p Le color due to t he f'o rrnaf ion of pmrexideAdd a drop or t wo of caustic soda, a deep blue. ooLor , moi s t e n with water and evaporate to drynessthe color disappearsHurexide is destroyed by this treatment and. the test dist·ineuishes uric acid from xauthin and guan i n , Uric acid stones' var-y Ln size, are quite hard and cenerall:' colored ye Tl ow or brown. 2" Fil tr6.te"Ia:' c ont a rn armon i um chlorideTo t e s t for nlTlOnia, heat the solution with sodium carbonate: anmonf a is recogni~ed by its odor, alkaline reaction, etc. II The Povder but becomes lea1Te sac black ollsiderable owing to the ore;anic substances present, residue. Digest a little of tIE finAly powdered stone in dilute hydrochloric ac iel warmi ng gentl:r: effervesence shows the presence of o ar-bonat e s , (a) Complete solutionuric ac id is absent .. (b) Incomplete solution t he residue may contain uric acid proteid substances, epithelial cells, etc. The' Gen8ral appearance or a microscopic exara i n at ion VIilJ. dec ide this. l lake the murexide testI~ any case the solution is to be invGstincted further. To a small pert ion of the s oLut ion add sod Iurc c ar-bonat e ; boil an d test for a-mon i a Dilute th e remainder of the so Lut ion with water, f i1t~r, make fain""ly a.LkaL'ine Ylith armcn i a and acidulate with acetic acid. Either an appr-ox» u.!latel:r clear or a c Loudy solution r e su.l.t s , The latter deposits Senerally a whi te powdery prec LpLt nt e , The ~rellowish "Nhite flakes Y(1ich are s oroet trne s seen in. the liqllid consist of iron phosphate. Filter, dissolve in h:rdrochloric acid and add potassium f'e r-r-oc yan Lde-« bLue color (Prussian blue) The white precipitate consists or- calcium . oxalate" Filter, (if the quantity is not too sna Ll) vash w'it.h water, dry and 510';' on the platinum foil. The c a Lc Lun oxalate burns to calc i um car bonat e and calc iun oxide. To the re s Ldue add a drop of hot wat e r and test the reactiona LkaLi ne , ac i d If'y w i th hydrochloric acidef'f'e r-ve se nce , The filtrate frOM iron phosphate or calcium oxalate, may contain calcium or Magnesium phosphate. 1.. To a sr.ial L quan t.Lt y of the filtrate add ur any'L n i t r-at e /U02 (N03)2/ a yellouish whf t e pr e e Ip t t at e of' u:nml~' phosphate shows the presence of phosphoric acid .. 2 To the remai:-lder of' the filtrate add amL"1oninumoxalate; white pre ..... cipitF_te shors calciumWarm, filjer and make alkaline 'Nith ammonia crystalline precipitate of ar''.moninUL''1 maGnesium Ilhosphate s11o"-{sthe presenna of maGnesium" 0 QUAN1.ITATIVE fu~!uJYSIS OP URINE. In all quantitative estimations, it is absolutely necessa.r~r to use well mixed 24 hours (night and day) urine.. The vessel used as a receptacle should be k.::-pt closed as much as po s s LbLe during this t tme and if necessary, thymolor some other disinfectant should be added to prevent putrefaction" }!leasure as acctlratel~r as possible the quantity of urine vo ided du ring the 24. hours, us i ng a dr~T craduated cylinder 0 DETERHINATlon O:? sPECI3i'IC GAVITY .. If tho urine is clear and wi hout a deposit, the specific gravity may be de t e rm i.ne d at once; ot he rw i se it will be necessar~r to clarify ... if urates have been deposited, warm sentl~r until solution' folloivs and a'llo'll to cool~ if suspended particles are present, filter .. 1,_, By mean s of the Hydrometer (urinometer) The u r i ne whose specific gTavi ty-:[stobeQetermined is pl?-cecr in a wide cylinder and to a void foaming the liquid should be allowed to run down the side of the vessel" The hydrometer is introduced into t.he liquid and the specific o gravity is read on the steM of the instrument DETER!UNATION OF rOTAL SOLIDS .. The amount of solids can tle caluclated 1vith a stlfficient degree of accuracy for clinical pur-po se s by I'1ultiplyinC the last two figures of the specific grqvity by 2.33 (for adults) or by 1.66 (for children) the nunbe r obtained indi cat I ng the amount of so lids m every 1000 cubic centimeters of urine" Example Spa gr" .; 1.03030 x 2.33 ;.:;69 9 grams · in 1000 subic centimeters. DE'T'F.mU:'~ATI ON OT' CHI_OEInES. R~srnt(s:xx Heagent sand apparatns nece s s ar'y (Reagents are' prepared) Cal A so tuti on of silver nitrate of S11Chstrnngth that one c ,e , corresponds to ten ~illiBrams of soditun' chloride" . (b) A solution of potassium chromate. (1:20). (c) oxidation mt xt ur'e (3 })artslX.ctf. of dry potassi1.un nitrate - one r;art of dry sodium carbonat e , ) \d) Powdered calcium carbonateo >e) 011.eburette complete wi th float and stand. \f) one pipet te 110ee ) e (g) Two porcelain crucibles with covers. Place in crucible about 4 grams of oxidation mixture and measure 10 c c , of urine into each. Evaporate over the water-bath to dryness , and he at very carefully over a free ~rame, be 6innine at the top and working gr-adua l Ly t o var d ·the bottom of the crucible,until the material has become whiteAllow to cool, add a little vater, heat on the waterbath and transfer the material to beakersAcidif~r faintl~T with nitric acid and warm Geiltly to expell the carbon dioxide.. Neutralize the slight excess of ncitric acid wi t h a small quantity of calcium carbonate, add a few drops of 11ota~sium chromate and titrate to a faint red color with silver nitrateo Q Read off the number of cubic centimeters of silver I.titrate used and mu.ltiply 'by QI~X 0 01" This gives the amount of chlorine as sodium chloride contained in 10 cc of urine» From this number can. be reck .... one d t h e amount of sodium chloride in the total quantity of ur me vo Ide d , AJ.b.umi:;~~ and sugar, .if present, shou.Ld be removed before the urine is add9d to the oxidation 'mixture, so as to obviate losses from frothing Which wou.Ld c t her-w I se oc cur" 0 0 DETERHINATION -----.-·-·~_ .. ~ 0;;' SULPHATEs" .. .,.,..~"'""O*_,..-'-'- ......... ,-..--·". ...... ·"Il"',.£4'C·,"'"_I... Re.age n t s and apparatus _ necessary (Re ag en t s are prepared): ~ la.) Al.ka Li ne bar-I um chloride mixture (2 vo Lumes of a saturated solut ion of ba.rium hydr at e and 1 volume of a saturated solution of bar-Ium chloride) " {b) Saturated solution of barium chloride" ~c) 'I'"lVQ a sh'Le s s filter pape rs , d~.Two p.orDelain crucibles with cOVRrso e) A measuring flask 100 cco f) a pipestem triabgle. 10 S:ctal Sulphates.·· To 100 c c , of clear ur ine (in case it is c.onH i--,"'~ ~ c erit r a t e d % GOcc to which GOcc of water is added) contained in a beake r , add 10ce or hydrochloric acid and heat over a free f' Lame to gentle boiling ~ Aft er b o i 1 I ng a bout ten rri nu t 8$, add a p inch or' two of pOWdered. potassinm pe r'manganat e and continue to bo I L, I:f after this addition and subsequent boiling a light amber colored fluid does not repultJ add ano t he r pinch of pe rrnang ana t e and cont Inue tohoil (u sua.LLy 1/2 gram of permanganate is sufficient to brine about this result) Continue to boil until the solution is perfectly cleara Remove the flame and add about lO·~l5> cc .. of barium chloflide solution that has be en prt:~vir)usly heated to boiling" Stir the liquid with 2: class red, and &.ll()v/ to stand on a bo i Li ng wat e r--bat h for ten rnf.nut e s , At the end of t.h.i s time the b ar Lum su Lphat.e has for the most part fallen to the be t tom of' the breaker and t he supernatant liquid has bec orne c Le ar '" }l':it an as h i e s s filter Lnt o a suitable funnel; moisten it "lith a very dilute so Luti on of hydrochloric acid and transfer the barium su.Lphat e t o the fi .Lt e r (1'he fi 1 tr at e should be perfe c t ly c Lear ) Wash with hot water until the filtrate no loneer gives a cloudiness with s.t Lvor n i tr-at e-. Wash once with alcohol and then with ether~ Allow the ether to evap,)rate and transfer the filter paper and. barium sulphate to a weighed crucible Place the crucible en a pepestem tri-. angle and hoat carefull:r unt.il the filter is' carbonized then i~cline the cruGi"ble ar..d 810';1 l!.1:~i I the re sidue is whi ts ... Allow the erGC i ble to cool ir.:. ,a de'sicatc.\J' and weigh" The ·:mi.ght of the barium sulphate multipl:l.ed b:T 0,4206 gives the al:'1(Hmtof 81.11phuric acid and by 0,,34335, the quan.ti ty cf 8n1.plmr trioxide in the amount of urine used for the a.nalysisr, 2,:,. Con,jiJgate f1ulphates·~ lUx 100cc of clear urine with an equal colu~iie-·c~J"---2-1l~-2]j{EL'T:rli8-soiution of barium chloride., Stir the mixture thol~out:;hly an.c1 after allowi;:lg to stand a few Plimltes; filter' through a dr·y f'ilt:~:cs collecting lOOeR" of t he filtrate in a d:sy IOOcc ~ measuring flasJ'~c T'ransfer' the lOOcc" of ciltrate to a beaker, acidjf~T with lOcco 01' hyd.:-c(;chl·:)rjc 8r:id boil ten l'1inutes and heat over a boiling vrater .... ~ bath UTJ.t:Ll. sup2rnatant liflUid is clear c 1'he precj.pitated barium sulphate' is removed to an ashless fUter, wash'ed, dried., i!)cin.erati3d; weighed~ etc. exactly as X under "TOrl'AL SULPHATES"o I - ~" - "-,.. ~ ".:.>. -':!' "">c.-" .""'~ __.' _._-~_._.- ... y No. 160 DETERMINATION OF URIC ACID. FOlin's; modification of Hopkin's Method. Apparatus and reagents required. A burette graduated in tenths. Amr;oniumsulphate. 10/,S'; Solution of ammoniumsulphate. n 20 potassium permanganate solution. 1. In normal urine without deposit. to 100 c c , 'of the urine in a beaker, add 10 gr-ams ammon tum sulphate; stir until COMpletely dissolved, and add anmond.a water, until the react ion is ver-y faintly alkaline. Allow the mixture to stand 2 hour s , Filter and wash the precipitate with IO}:; solution of ammonium sulphate, unt il the waahfng s are free' :rrom chlorides, Rinse the precipitate i!lto a 200 c.c. beaker, and dilute the mixture to 100 c.c. then add 15 c.c. concentrated sulphuric acid, and b.:itrate while hot. One e oC. n/20 potassium parmangauat s so Lut ion is equivalent to .00375 Uric acid,.OOl must be added, as a correction to the result obtained. In acid urine with -de po sLt , If the deposit be'onlYl1ric acid or urates, there is but little clancer in neglecting ,it. Add the ammon tum chloride to bring down the uric acid that rema ins in solution, and treat the entire precipitate as directed above. The deposit most likely to lead to error wou l d be on of 'e yst in- If this be suspe cted a few drops of ammon i a s hou Ld be added and the urine warmed. The chloride of ammcnf um should be added while the sample is still warm. 3. In Alkaline Urines. If the---dElrJo-sIT-of-'-l)hosphatesbe very Lar-ge , it may be well to filter it off, and wash with hot water: otherwise it May be neglected. The anmo n t un urate comes down on saturation with ammonf.um chloride nuc h __ more rapidly in alkaline urine. The only objection to adding a few a!''l(lonia in all cases is the precipitation of the phosphates and the fact that the urate precipitate appear-s to absorb mor-e pLgmen t from the alkaline urine., Continue the process as in 1. Ll" In Highly P!ernel?-ted Drines. Sc\metimes though very rarely the uric acid crystals ':lay be so much pigmented as to suCgest that an error in titration might result. In such vc a se s the original urate precipitate may be deaoznpose d in the presence of alcohol. After washinc the precipitate off the filter, 95% alcohol equal in ~lount to the water present is-added, and after acidifying , the liquid is cautiously heated to boiling in the usual ways ' and then, wit h a watch crystal placed over the beaker, it is digested for sone time over the water-bath - The separated crystals should be well washedIn the urines that contain bile, the biliary pigments may come down in considerable quantity,but, in spite of this., the Ultimate errorar1pears to be small. 2. DETER:,IINATION OF UR.8A. If albuy~in is present it m11stfirst be removed hy boiling (after acidifyine with acetic acid if necessary) and :rilterine off ,the flakes of c08clulated proteid. No , 17 0 / A.pparatus and reagents required. Doremus Uremeter. Alkaline Qll solution of sodium h~Tporbromite (10 gr-ams sodium hydroxide 25 c c water, to which 2.5 c.c. Brownine and 10 c.c. ¥ water have een added. 1% Solution of urea. he solution should be freshly made. Titltine the meometer, pour in enough hypobromite solution to completely fill the long arm, and pass the bend. Draw the urine into the pipette to the gradnation. Pass the into the me ome t e r- as f'a r- as the bend, and c ompr-ess the The nitrogen liberated, will colle ct. of the tube. Each division indicates .001 gram,of urea, in c. ur in.e. IiIake in the upper , a check de t erminat ion, wi th the connect the r~sult accordingly. 1/1 urea solution, and