this file - ICOM-CC

The Use of Glass Bricks in Architecture
in the 19th and 20th Centuries: A Case Study
Kristel De Vis,1 * Patric Jacobs,2
Joost Caen,1 and Koen Janssens3
kristel.devis@artesis.be
Conservation Studies
Artesis University College of Antwerp
Antwerp, Belgium
1 Department of Geology
and Soil Science
Ghent University
Ghent, Belgium
2 Abstract
Nineteenth- and 20th-century glass was used in buildings
in a variety of surprising and innovative ways. Engineers
(e.g., Gustave Falconnier), architects, and designers (e.g.,
Frank Lloyd Wright) applied known theories of light refraction to guarantee maximum light while guarding privacy in an environment in which growing cities required
radical solutions to the problem of lighting storefronts and
sidewalks. The idea of using light refraction was translated
into the use of glass prisms and glass bricks, which refract
light into previously unlightable spaces, particularly those
in deep courts and wells or on narrow streets bordered by
tall buildings. The light refracted through the application
of these glass elements brings natural light into factories,
homes, and offices.
These glass elements are now over a century old, and
they are disappearing evidence of a time in which these
architectural glass elements were more often used and
more varied than similar elements are today. The diversity
of materials applied (e.g., concrete, mortar, cast iron, and
blown and semi-industrial glasses) will present future
conservators with a serious dilemma.
194
MiTAC
Department of Chemistry
University of Antwerp
Wilrijk, Belgium
3 This paper focuses on a case in which semi-industrial
glass bricks were applied in an old paper factory in Huy,
Belgium. Patent history, material, and initial analysis results will be discussed.
Keywords: glass bricks, Falconnier, Papeterie Godin,
degradation
Introduction
At the dawn of the Industrial Revolution, the distribution
of light into previously unlightable spaces such as deep
courts and wells, narrow streets bordered by tall buildings, and factories was a primary issue.
The basic concept of light refraction to introduce more
light in an inferior (or interior) space, using various forms
of glass, had already resulted in a patent for E. Wyndus
(GB no. 232, Glass and Lamps for Ships, Mines &c.) in 1684,
as it did later in more extended—but Wyndus-based—
projects such as those by R. Cole (GB no. 372, Forming
Glass into Conical Figures and Lamps, 1704), A. Pellatt (GB
no. 3,058, Lighting in the Interior of Ships, Buildings, etc.,
1807), and G. Preston (GB no. 4,222, Deck Glass Rim,
Safety Grate for Ships, 1818). These inventions were primarily intended to improve 17th-century street lighting
Figure 1
Falconnier briques are sealed
with a pastille of molten glass.
(Photo: K. De Vis)
in London and other cities, and they eventually developed
into deck lights that were used on ships to illuminate
deeper spaces.
In the 19th century, the basements of commercial
build­ings often extended into the space beneath the sidewalk and occasionally even under the street. To make this
possible, heavy cast-iron columns supported the sidewalk
and the roof of the vault. Allowing daylight into the cellars or vaults required imaginative engineering because
lighting with gas or kerosene presented hazards in these
enclosed spaces, where ventilation was limited and the
possibility of fire was ever present. The ingenious invention of the “vault light” allowed natural light to be filtered
through the sidewalk into the basement while providing
a surface rigid enough to support pedestrian traffic (Gayle,
Waite, and Look 1998, p. 51). Theodore Hyatt’s patent
(U.S. no. 4,266, Illuminating Vault Cover, 1845) is a variation of E. Rockwell’s patented vault light (U.S. no. 8,058X,
1834), which was extensively described in the 1834 Mechanic’s Magazine: “Every citizen is aware that the common vault light[s], or grating, which may be seen on our
sidewalks at every few steps, are not only unsightly to the
eye, but often positively dangerous. Very frequently they
are found loose, often broken, with a bar or two out and in
winter so slippery as to render it hazardous to step upon
them” (Knight 1834). This confirms the presence and
common knowledge of vault lights in pavements. The new
vault lights of Hyatt and Rockwell were implemented with
convex glass in the center to afford light that entered and
radiated on all sides (ibid.). Some of the applications introduced by these two inventors are still visible on streets
in New York City (Stuart 2003).
Prism glass was further developed by James G. Pennycuick, a British inventor, who filed a U.S. patent application (no. 312,290, Window Glass) in 1882. This became
the basis of the Radiation Light Company of Chicago
(1896) and, one year later, the Luxfer Company (Neumann 1995a).1 Hollow glass blocks, invented as an alternative means of providing light, have been used in ceilings, walls, and floor panels. Unlike prism glass, they are
still employed in architectural applications.
In this paper, the initial results of a case study on Falconnier blocks will be discussed. The study focuses on
the glass block and dalle de verre technology that is found
in western European architecture.
A Western European Application:
Brique de verre (Glass Block/Brick)
When Gustave Falconnier (1845–1913) of Nyon,
Swit­zerland, presented his briques en verre soufflé at the
meeting of French civil engineers in Paris in 1895 (Anon.
1895, pp. 573–574), he could not have anticipated the im­
pact of his invention on 20th- and 21st-century architecture. His glass blocks were produced by mold blowing.
The glassblowers, who perspired freely and thus drank
considerable quantities of water, breathed out a moistureladen air that ultimately condensed. This detracted from
the appearance of the blocks, which were sealed with a
marked pastille of molten glass (Fig. 1). The sides of the
bricks were recessed to take mortar, and the bricks were
laid up like masonry bricks, with or without an embedded metal reinforcement. The construction of these glass
1. Glass prisms are a type of architectural glass element designed to
bring more daylight into the dark interiors of factories and densely built
urban centers. The Luxfer Company was studied by Dietrich Neumann of
Brown University, and the results of his research can be found in Neumann 1995a and 1995b.
195
Figure 2
Glass bricks at the entrance to a private building (Villa Andreae, Kollum,
the Neth­erlands). (Photo: L. A. E. Lutz)
blocks, as well as the formation of complete walls or even
conservatories (Fig. 2), is well described and illustrated
in patents dating from 1886 to 1907.
Describing the improved technology of his glass bricks
in his second patent (CH no. 212, Briques en verre soufflé
avec cachets de verre fermant l’ouverture ayant servi à la soufflure, 1888), Falconnier compared his first bricks (FR no.
179595, title unknown, 1886) with “les bouteilles ordinaires.” These were bricks that were open on one side, and
they were closed on-site, during the assembly of the wall,
with paper, cloth, mastic, or ciment de bois. Despite careful
construction and frequent maintenance, it was not possible to prevent all intrusions into the glass block because
of the effects of condensation. It is not clear whether this
kind of glass brick can still be found on-site. After 1888,
Falconnier presented bricks that were closed with a pastille of molten glass and marked with the trademark and/
or license number. He also introduced several variations
on his basic patents, such as briquetage légers et écono­
miques (lightweight and economical bricks) with a less
complicated construction method (CH no. 48, 1888) and
196
De Vis AND others
briques de verre pour réflecteurs (bricks that could be used
as reflectors; CH no. 7754, 1893). These bricks, with bigger glass surfaces, were coated with a metallic layer and
covered with a preserving varnish. When light rays fell
upon the glass brick, they penetrated into the brick and
were radiated by the several coated surfaces so that the
reflected light was of a higher intensity. Falconnier’s two
last improvements of the glass brick were patented in 1904
(CH no. 28315, Construction perfectionnée en briques creuses
en verre) and 1907 (CH no. 41374, Construction en briques
soufflées en verre).
Several European companies were allowed to make
the patented Falconnier bricks, including Adlerhütten G.
Mayer & Co. in Penzig, Germany (Sommer 2003, p. 156);
Glashütte Gerresheim in Düsseldorf, Germany; and the
Haywards Company in London (Winterton 1953, p. 9;
Hermans 2009). In addition, these bricks were quite
popular with architects such as Hector Guimard, Auguste
Perret, Le Corbusier (Charles-Edouard Jeanneret-Gris)
(Schittich, Debord, and Drey 2001, p. 11), Eduard Cuypers, and Hendrik Petrus Berlage (Stokroos 1994, p. 37).
A Case Study: The Old Paper Factory Godin Frères
in Huy, Belgium
Papeterie Godin is located in the French-speaking part
of Belgium, near Liège, between Marchin and Huy. Between 1840 and 1967, the Godin family produced all
kinds of paper. The company had various technical installations, including a pulverizer, a continuous-feed paper
machine, gluing units, and washing and bleaching quarters. On several occasions, especially during the 19th century, the company was praised as a model organization
for its technological advancement from windmill-powered energy to hydraulic wheels driven by steam, and for
its ability to offer employment to 1,500 skilled workers
(Didot 1854, p. 115; Scheler 1865, p. 186). After the com­
pany closed in 1967, the site was abandoned. In 2005,
when the village of Marchin decided to build a new commercial area there, the original semi-industrial Falconnier
bricks were discovered. Fortunately, developers were able
to save the bricks in the summer of 2009, before the razing of the original building, which was thought to have
been contaminated. These bricks are the only known patented Falconnier bricks that survive in Belgium.
General Description of the Assembly
In the summer of 2009, only the washing and bleaching
quarters of the Godin factory remained to be demolished
(Fig. 3). The windows on the upper floors were decorated
with translucent bricks of various colors, while only transparent bricks were found on the floors below. Each window consisting of translucent glass had one glass brick
colored amber, green, or red. All of the bricks were colored throughout, except for the red ones, which were
made by flashing (red on white). The technique of flashing
glass is well known in the manufacture of vessel glass as
well as sheet glass. In both processes, a semimolten bubble of colorless glass is dipped into a pot of red glass, with
the colored glass forming a thin coating on the surface.
Afterward, the flashed bubble could be formed into a sheet
of glass (by the cylindrical or spinning method) or pressed
in a mold to form bottles or a Falconnier brick (Wigginton
2004, p. 26).
The glass bricks were laid up like masonry bricks, with
a layer of mortar 0.8–1.2 centimeters thick. Although the
windows had been constructed more than 80 years earlier,
they were stable and would have been able to last much
longer. The bricks were removed from the window openings with a hammer and chisel. Unfortunately, during this
process, some of the bricks were broken. The damaged
bricks were numbered, cleaned, rejoined with tape, and
stored in plastic bags.
One of the red bricks was examined with a microscope.
It was cracked from the bottom to the top, which permitted observers to study the construction and thickness of
the glass layers and the glass seal, and to form a better idea
of the internal degradation of the brick. Primary analysis
of the glass composition was accomplished using SEMEDS.
General Description of the Red Falconnier Brick
Only a few types of Falconnier bricks are known: square
(no. 6), watch with band (no. 8), squashed hexagon (no.
9), and four regular hexagons (nos. 7, 7½, 10, and 11). All
Figure 3
The old Godin paper factory in Huy,
Belgium, June 2009. (Photo: K. De Vis)
the use of glass bricks in architecture in the 19th and 20th centuries: a case study
197
Figure 4
Falconnier bricks nos. 6, 7, 8, and 9 (patent scans).
of these bricks are rare today, but no. 8 is the most common kind, and it was found at the Huy site (Fig. 4).
The brick made in flashed red glass was sealed with a
pastille of molten glass marked with the inscription “Falconnier [ ] 774 D.R.P.,” which probably refers to patent
number 41774 of 1887 as a German patent (Deutsches
Reich Patent). Unlike the brick, the pastille was made of
transparent glass. The side of the brick, to the left of the
pastille, is embossed with “Falconnier,” and the poorly preserved embossing on the right side reads “[ ] France [ ]
ique + [ ],” which may refer to the inscription “FALCONNIER / DEP FRANCE BELGIQUE + nnn / FRANCE”
that can be found on a similar brick in the Museum of
Modern Art in New York City (2308.2001.1-3). In the
inscription, “nnn” refers to the style number, which is
most often 8. In addition to the complete brick, half- and
quarter-size bricks for squaring up the window were found
on the site. The red brick measures 13.9 by 19.7 centimeters, and it weighs 0.82 kilograms (Fig. 5).
In modern glass bricks, which are produced by pressing two halves together at 600°–700°C, redeposits of evap­
orated alkali oxides can be found on the interior front
surfaces. These surfaces can react with H2O and CO2 from
the residual brick atmosphere, leading to the formation of
an alkali-rich silicate hydrate layer; this layer, in turn, can
produce corrosion where NaHCO3 crystals finally grow
(De Moraes and others 2008). Preliminary traces of corrosion can be seen on the inside of the Falconnier brick,
which are indicated by the iridescence of the glass layer.
The surface shows a rainbowlike effect without flaking
or any other form of active degradation, but on a microscopic scale a progressive breakdown of the siliceous layer
may already have occurred (Newton and Davison 1997,
198
De Vis AND others
p. 157). The interior surface of the brick, which remains
pristine from its formation in the mold and its sealing
with the glass pastille, may react with the residual gas
mixture enclosed in the brick. These bricks are thought to
enclose air that is more or less rarefied because, as was
noted earlier, the glassblower, who was obliged to drink
water, exhaled a moisture-laden air that ultimately condensed into the brick (McGrath and Frost 1961, p. 64).
Because the Falconnier patents provide no information on the composition of the glass, SEM-EDS measurements were performed on the red brick, using a JEOL
6300 scanning electron microscope equipped with an
energy-dispersive X-ray detector (Reed 2005, p. 76). The
spectra were collected for 100 seconds by using a 2 nA
electron beam current, an accelerating voltage of 20 kV,
Figure 5
Red Falconnier brick no. 8. (Photo: K. De Vis)
Huy - Red Glass Brick
100000
White Glass Layer
Red Glass Layer
Si
10000
Pb
Na
Ca
1000
K
Ca
Pb
100
10
1
0.1
0
2
4
6
8
10
12
14
16
18
20
keV
Figure 6
XRF spectrum of the bulk layer and the red surface layer.
and a magnification of 500X. These parameters were
found to be suitable for quantitative analysis of glass
without significant diffusion of sodium during the irra­
diation (Schalm 2000, pp. 45–71). The net intensities
were calculated with the AXIL (Analysis of X-Rays by
Itera­tive Least Squares) program and were quantified
by means of a standardless ZAF program (Schalm and
Janssens 2003).
The red and white/transparent layers were measured
and quantified. The basic composition of the transpar­ent layer of the brick corresponds to that of a multicomponent soda-lime-silica glass, which was the most
common type of glass in the 20th century. It contains
about 75.5% SiO2, but it has a reduced amount of Na2O
(10.6%; 12%–18% is usual). The amount of K2O (6.5%)
is within the normal standards of 5%–12%. The red layer
is also a soda-lime glass, but its levels of SiO2 and Na2O
decrease significantly, to 57.9% and 1.4% respectively;
its K2O level (8.0%) remains within the standard range.
Meanwhile, a new material was added to the batch. A
quantity of 30.5% PbO makes the glass relatively soft,
and it produces a brilliant refractive index. This optical
character may be the reason for applying the lead glass on
the exterior of the brick: so as to achieve a wider range of
diffraction (Fig. 6). Because of the limits of SEM-EDS,
the coloring agent for the red glass could not be detected.
A study of the coloring agent will be part of further research.
Conclusion
The glass bricks of the old Godin paper factory shed new
light on the history of early modern architecture and the
development of its glass elements. The complex general
conditions of architectural production have received far
less attention than they deserve. Although patents can be
discovered and studied, it is important to determine how
the materials were invented, promoted, and eventually incorporated into the architecture of that time. The bricks
from Huy are the only ones known in Belgium that confirm the descriptions in the patents.
The fact that the glass contains various batch materials
with different amounts of metal oxides will lead to more
extensive analytical research on both the physical and the
chemical properties of the glass.
the use of glass bricks in architecture in the 19th and 20th centuries: a case study
199
Acknowledgments
This research is part of Kristel De Vis’s Ph.D. dissertation
“The Application of Tiles, Bricks, and Blocks of Glass in
an Architectural Context Applied in the 19th and 20th
Centuries: Materials, Degradation Phenomena, and First
Conservation/Restoration Approach” at Artesis University College of Antwerp, the University of Antwerp, and
Ghent University, Belgium.
References
Anon. 1895
Mémoires et compte rendu des travaux de la Société des
Ingénieurs Civils de France, fondée le 4 mars 1848, v. 2, Paris,
1895.
Neumann 1995a
Dietrich Neumann, “‘The Century’s Triumph in Lighting’: The Luxfer Prism Companies and Their Contribution to Early Modern Architecture,” Journal of the Society
of Architectural Historians, v. 54, no. 1, March 1995, pp.
24–53.
Neumann 1995b
Dietrich Neumann, “Prismatic Glass,” in 20th-Century
Building Materials, ed. Thomas C. Jester, Washington,
D.C.: National Park Service, 1995, pp. 188–199.
Newton and Davison 1997
Roy Newton and Sandra Davison, Conservation of Glass,
London: Butterworth-Heinemann, 1997.
De Moraes and others 2008
Flavia de Moraes and others, “Corrosion and Crystallization at the Inner Surfaces of Glass Bricks,” Journal of
Non-Crystalline Solids, no. 354, 2008, pp. 284–289.
Reed 2005
S. J. B. Reed, Electron Microprobe Analysis and Scanning
Electron Microscopy in Geology, 2nd ed., Cambridge: Cambridge University Press, 2005.
Didot 1854
Ambroise Firmin Didot, L’Imprimerie: La Librairie et
la papeterie à l’exposition universelle de 1851. Rapport du
XVII e jury, Paris: Imprimerie Impériale, 1854.
Schalm 2000
O. Schalm, “Characterization of Paint Layers in Stained
Glass Windows,” Ph.D. diss., University of Antwerp, 2000.
Gayle, Waite, and Look 1998
Margot Gayle, John G. Waite, and David W. Look,
Metals in America’s Historic Buildings, New York and London: Norton & Company, 1998.
Hermans 2009
T. Hermans, adviser, Rijksdienst voor het cultureel Erf­
goed, the Netherlands, conversation with Kristel De Vis
on Falconnier brick producers, February 22, 2009.
Knight 1834
J. Knight, ed., “Rockwell’s Patent Vault Light,” Mechanic’s Magazine, Register of Inventions and Improvements, v. 4,
July–December 1834, pp. 91–92.
McGrath and Frost 1961
Raymond McGrath and A. C. Frost, Glass in Architecture and Decoration, London: Architectural Press, 1961.
200
De Vis AND others
Schalm and Janssens 2003
O. Schalm and K. Janssens, “A Flexible and Accurate
Quantification Algorithm for Electron Probe X-Ray Microanalysis Based on Thin-Film Element Yields,” Spectrochimica Acta, Part B, 58, 2003, pp. 669–680.
Scheler 1865
Aug. Scheler, Annuaire statistique et historique belge,
Brus­sels: Brussels Imprimerie, 1865.
Schittich, Debord, and Drey 2001
Christian Schittich, Didier Debord, and Sabine Drey,
Construire en verre, Paris: Presses Polytechniques, 2001.
Sommer 2003
Siegfried Sommer, “Glasbauten,” in Technik-Wissen,
1900–1915.14, ed. Reinhard Welz, Mannheim: Vermitt­
ler Verlag e.K., 2003.
Stokroos 1994
Meindert Stokroos, Bouwglas in Nederland: Het gebruik
van glas in de bouwnijverheid tot 1940, Amsterdam: Stadsdrukkerij Amsterdam, 1994.
Stuart 2003
Diana Stuart, Designs Underfoot: The Art of Manhole
Covers in New York City, Sharon, Connecticut: Lyons
Press, 2003.
Wigginton 2004
Michael Wigginton, Glass in Architecture, London:
Phai­don Press, 2004.
Winterton 1953
L. C. Winterton, Years of Reflection, 1783–1953: The
Story of Haywards of the Borough, London: Harley Publishing Co. Ltd., 1953.
the use of glass bricks in architecture in the 19th and 20th centuries: a case study
201
Glass and Ceramics Conservation 2010
Interim Meeting of the ICOM-CC Working Group
October 3–6, 2010
Corning, New York, U.S.A.
Hannelore Roemich, Editorial Coordinator
ICOM Committee for Conservation
in association with The Corning Museum of Glass
© 2010 International Council of Museums
ICOM-CC Glass and Ceramics Working Group Committee:
Gerhard Eggert
Coordinator
Hannelore Roemich
Editorial Coordinator
Review Panel for Papers
Renske Dooijes, Leiden, The Netherlands
Gerhard Eggert, Stuttgart, Germany
Agnès Gall-Ortlik, Barcelona, Spain
Isabelle Garachon, Amsterdam, The Netherlands
Stephen P. Koob, Corning, New York, U.S.A.
Laurianne Robinet, Gif-sur-Yvette, France
Kate van Lookeren Campagne, Amsterdam, The Netherlands
For The Corning Museum of Glass:
Editor: Richard W. Price
Design and Typography: Jacolyn S. Saunders
Editorial Adviser: David Whitehouse
Proofreader: Monica S. Rumsey
Reference Librarian: Gail P. Bardhan
ISBN: 978-0-87290-182-7
Library of Congress Control Number: 2010931220
All rights reserved. No part of this publication may be reproduced,
stored in a retrieval system, or transmitted in any form or by any
means, whether electronic or mechanical, including photocopying,
recording, or otherwise, without the prior permission in writing of
the publisher.
Cover Image:
Cire perdue figure made by Frederick Carder
in the 1930s or 1940s, with a repair in which
the epoxy is badly yellowed. The Corning
Museum of Glass (59.4.426).