Cathedral glass is the name given commercially to monochromatic sheet glass. It is thin by comparison with ''slab glass'', may be coloured, and is textured on one side. The name draws from the fact that windows of

stained glass Stained glass is coloured glass as a material or works created from it. Throughout its thousand-year history, the term has been applied almost exclusively to the windows of churches and other significant religious buildings. Although tradition ...

were a feature of medieval European cathedrals from the 10th century onwards. The term ''cathedral glass'' is sometimes applied erroneously to the windows of

cathedral A cathedral is a church that contains the ''cathedra'' () of a bishop, thus serving as the central church of a diocese, conference, or episcopate. Churches with the function of "cathedral" are usually specific to those Christian denominations ...

s as an alternative to the term ''stained glass''. Stained glass is the material and the art form of making coloured windows of elaborate or pictorial design.

Manufacture

Traditional methods of making coloured glass

Very early architectural glass, like that sometimes found in excavations of Roman baths, was cast. The molten glass was poured into a mold of wood or stone to make a sheet of glass. The texture of the mold material would be picked up by the glass. By the time

was being made, the glassblowing pipe was in common use, so hand-blown (or mouth-blown) sheets were made by the

cylinder 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 a ...

and/or crown glass method. Casting came back as a common technique when

rolled glass Rolling is a type of motion that combines rotation (commonly, of an axially symmetric object) and translation of that object with respect to a surface (either one or the other moves), such that, if ideal conditions exist, the two are in conta ...

began to be manufactured in the mid-1830s and as glass jewels (also used for architectural glass) became popular. Rolled glass is not as rich and translucent as hand-blown glass, but it is much cheaper and is made in a variety of colors and textures, making it a useful decorative material. Chapel glass ca1900 a

Modern methods of making cathedral glass

This type of rolled glass is produced by pouring molten glass onto a metal or graphite table and immediately rolling it into a sheet using a large metal cylinder, similar to rolling out a pie crust. The rolling can be done by hand or machine. Glass can be "double rolled", which means it is passed through two cylinders at once to yield glass of a certain thickness (approximately 3/16" or 5 mm.) Glass made this way is never fully transparent, but it does not necessarily have much texture. It can be pushed and tugged while molten to achieve certain effects. For more distinct textures the metal cylinder is imprinted with a pattern that is pressed into the molten glass as it passes through the rollers. The glass is then annealed. Rolled glass was first commercially produced around the 1830s and is widely used today. It is often called cathedral glass, but this has nothing to do with medieval cathedrals, where the glass used was hand-blown. Cathedral glass comes in a very wide variety of colors and surface textures including hammered, rippled, seedy, and marine textures. It is made in the US, England, Germany, and China.

Uses

Cathedral glass has been used extensively in churches (often for non-pictorial windows) and for decorative glass in domestic and commercial buildings, both leaded and not, often in conjunction with drawn sheet glass and sometimes with decorative sections of beveled glass. It lets in light while reducing visibility and is an inexpensive, but useful and decorative material. While it does not have the richness and versatility of hand-blown glass, it has been used successfully for the creation of modern stained-glass windows in which the texture of the glass is treated, with the color, as a significant design element. File:Torun witraz piast 5 01.jpg, 19th-century domestic lead light with cathedral glass and bull's eyes File:Cerveny kostel okno adj straight.JPG, Church window with pale colours typical of early 20th century, Czechoslovakia

References

* Sarah Brown, ''Stained Glass, an Illustrated History'' 1995, Bracken Books, * Ben Sinclair, ''Plain Glazing'', 2001, the Building Conservation Directory

{{DEFAULTSORT:Cathedral Glass Windows Glass architecture Glass art Church architecture