Broad sheet is a type of hand-blown
glass
Glass is a non-crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling ( quenching ...
. It was first made in
Sussex in 1226.
Production
It is made by
blowing molten glass into an elongated tube shape with a
blowpipe. Then, while the glass is still hot, the ends are cut off and the resulting cylinder is split with shears and flattened on an iron plate. The quality of broad sheet glass is not good, with many imperfections and mostly
translucent
In the field of optics, transparency (also called pellucidity or diaphaneity) is the physical property of allowing light to pass through the material without appreciable scattering of light. On a macroscopic scale (one in which the dimensions ...
. Due to the relatively small sizes blown, broad sheet was typically made into
leadlights. The centerpiece was used for decoration in places where looking through the glass wasn't vital. If the piece was large, it was possible to see bubble tracks and strain lines.
Other methods for making hand-blown glass included
blown plate glass,
crown glass (introduced to England in the 17th century),
polished plate glass and
cylinder blown sheet glass Cylinder blown sheet is a type of hand- blown window glass. It is created with a similar process to broad sheet, but with the use of larger cylinders. In this manufacturing process glass is blown into a cylindrical iron mold. The ends are cut off an ...
. These methods of manufacture lasted at least until the end of the 19th century. The early 20th century marks the move away from hand-blown to machine manufactured glass such as
rolled plate glass,
machine drawn cylinder sheet glass,
flat drawn sheet glass,
single and twin ground polished plate glass and
float glass.
Broad sheet glass was first made in the UK in
Chiddingfold
Chiddingfold is a village and civil parish in the Weald in the Waverley district of Surrey, England. It lies on the A283 road between Milford and Petworth. The parish includes the hamlets of Ansteadbrook, High Street Green and Combe Common ...
, Surrey on the border with
Sussex in 1226. In 1240 an order
was placed for this glass to be used in Westminster Abbey. This glass was of poor quality and fairly opaque. Manufacture slowly decreased and ceased by the early 16th century. The choice of this location
may have been due to the availability of sand, the abundance of
bracken (the ash of which can be used to make potash for soda glass) and the significant beech forests to provide charcoal as fuel for the kiln. Examples of glass from this area can be found in
Guildford Museum.
Whilst French glass-makers and others were making broad sheet glass earlier than this
notably William Le Verrier, Schurterrers and John Alemayne.
Between 1350 and 1356 Alemayne
secured orders for glass to be used in St. Stephens Chapel, Westminster and
St Georges Chapel, Windsor.
References
Glass production
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