This is your resource for exploring various topics in glass: delve deeper with this collection of articles, multimedia, and virtual books all about glass. Content is frequently added to the area, so check back for new items. If you have a topic you'd like to see covered, send us your suggestion. If you have a specific question, Ask a Librarian at our Rakow Research Library.
The technique of forming objects from rods and tubes of glass that, when heated in a flame, become soft and can be manipulated into the desired shape. Formerly, the source of the flame was an oil or paraffin lamp used in conjunction with foot-powered bellows; today, gas-fueled torches are used.
A separate ring of glass added to the base after the body of the vessel has been formed.
(1) The bench used by the gaffer while forming a glass object. Traditionally, this is a wide bench with arms, on which the gaffer rests the blowpipe with its parison of molten glass and rolls it backward and forward so that the parison retains its symmetrical shape during the forming process. (2)
A small cup in which a partial vacuum is created for cupping. Cupping is the technique of drawing blood to the surface of the body, usually for bloodletting.
A tool with two metal arms joined at one end by a spring. The distance between the arms is controlled by the glassworker, who uses jacks for a variety of purposes while shaping the parison (for example, to form the mouths of open vessels). This tool is also known as a borsella or pucellas.
Window glass made by inflating a large gather and swinging it until it forms a cylinder. The cylinder is then detached from the blowpipe, and both ends are removed with shears. Next, the cylinder (sometimes known as a muff) is cut lengthwise, reheated, and either tooled or allowed to slump until it
A technique adapted from metalworking. The object to be fashioned in glass is modeled in wax and encased in clay or plaster that is heated. The wax melts and is released through vents or “gates,” also made of wax, which have been attached to the object before heating. The clay or plaster dries and
A decorative effect that causes the surface of the glass to resemble cracked ice. This is achieved by repeatedly plunging a parison of hot glass into cold water and withdrawing it quickly. The thermal shock creates fissures in the surface, and these impart a frosted appearance after the parison has
A pair of bottles blown separately and then fused, usually with the two necks pointing in different directions.
(German, “gold between glass”) A type of decoration, produced in Bohemia and Austria in the 18th century, in which a design in gold or silver leaf is incorporated between two vessels that fit together precisely. Unlike Hellenistic and Roman gold glass, which is fused, Zwischengoldglas is bonded