Period Window Glass

A BRIEF HISTORY OF GLASS

To introduce this feature, Christopher

Salmond explains the types of glass

used through history and suggests

substitutes for those which are no

longer available

Walk slowly past the facade of a fine old

building and see how the reflections

from the windows distort, shimmer and

sparkle. The whole building comes alive

and seems to flash with colour and life.

Compare this to some of the carefully

restored buildings, which have been

reglazed with modem window glass. A

bland mirror like reflection of float glass

deadens the whole facade, robbing the

building of its original charm. Even where

a facade retains much of the original

glass, new frames or even repairs to sin-

gle broken panes that use modem glass

spoil the overall effect and can be de-

tected easily. Why is the difference so

marked and why does old glass fit so

perfectly into its surroundings? To an-

swer these questions, we need to under-

stand a little about the history of

glassmaking in this country and the par-

ticular process of manufacture.

GLASS MANUFACTURE IN THE UK -

CHRONOLOGY

Window glass was not produced in sig-

nificant quantities in this country until:

1226 BROAD SHEET was first made in

Sussex, but of poor quality, and fairly

opaque. Manufacture slowly decreased

and ceased by the early 16th century.

1330 The French glassmakers produced

CROWNGLASS for the first time at Rouen.

Some French Crown and Broad Sheet

was imported into the UK.

1620 BLOWN PLATE was produced in

London by grinding and polishing Broad

Sheet, and was used for mirrors and

Coach plates.

1678 CROWN GLASS was first produced

in London. This process predominated,

because of its finer quality until the mid-

19th century.

1688 The French produced POLISHED

PLATE in larger sizes by casting and hand

polishing.

1773 English POLISHED PLATE by the

French process was produced at

Ravenshead. By 1800 a steam engine was

used to carry out the grinding and polish-

ing of the cast glass.

1834 Robert Lucas Chance introduced

IMPROVED CYLINDER SHEET, using a

German process to produce finer quality

and larger panes. This glass was used to

glaze the Crystal Palace. The process was

used extensively until early in the 20th

century to make window glass.

From this period onwards machines

were developed to automate the

production of obscured glass and later,

window glass:

l847 James Hartley introduced a ROLLED

PLATE glass with obscured ribbed finish,

which is often found glazed in the roofs

of railway termini.

1888 Chance Bros introduced MACHlNE

ROLLED patterned glass.

1898 Pilkingtons introduced Hexagonal

Rolled WIRED CAST.

1903 MACHINE DRAWN CYLINDER

glass, invented in the USA, was manufac-

tured in the UK by Pilkingtons from 1910

to 1933.

1913 Belgium produced the first ma-

chine FLAT DRAWN SHEET glass. It was

first drawn in the UK in 1919 in Kent.

1923 First UK production of continuous

POLISHED PLATE gIass, using single grind-

ing system.

CROWN GLASS: Fig. 1 shows the glassmaker having spun the table of Crown, about to drop it

into a bed of sand (note the early version of virtual reality headgear !).

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CONTEXT 48