I contrived heretofore, a perspective by Reflexion.       —Sir Isaac Newton, c. 1668 The refracting telescope gave astronomers their first up-close glimpses of the heavens. Then, it began to frustrate them. At higher magnifications, the instrument’s glass lenses produced distorted images.

Why did such an important discovery occur so late in the … history of glass, and why was an accident necessary to bring it about?      – Donald Stookey, 1977 Crystals are usually a glassmaker’s enemy. When they form in glass, crystals can change the properties of the material in unwanted ways.

"If necessity is the mother of invention, then for the glass fiber industry, adversity is the father."     -William Boeschenstein, Owens-Corning Fiberglas, 1995 The world’s largest bottle plant stood empty. Prohibition and the Depression had crushed the demand for bottles. American bottle

Otto Schott, the pioneering German glass chemist, made a glass that could reliably do something that didn’t seem possible: endure sudden, uneven temperature shifts without shattering. The key, Schott discovered in 1882, was to have a critical amount of the element boron in the glass recipe. Schott

A late 17th- and 18th-century English drinking vessel engraved with a toast, a symbol (an orange tree, for example), or a motto supporting William of Orange (King William III, r. 1689-1702), or with his portrait. William III was a Protestant, and his political opponents were the Roman Catholic

A decanter with matching wineglasses, sometimes with a matching tray. wine sets wine-set Decanter set with 6 glasses

A type of goblet with the stem in the form of vertical, winglike flanges composed of trails arranged in a complex design that may include dragons, sea horses, and other creatures. The German term for a winged goblet is Flügelglas. winged goblets winged-goblet winged-goblets Flügelglas Winged Goblet

A glass globe intended to be hung in a prominent place to ward off the evil eye. witch balls witches balls witches ball witch-ball Witch ball

A type of English ale glass with a trumpet-shaped mouth, a long and narrow neck, and a small globular body. These glasses were often one yard (three feet) long. They contained about one pint and functioned like trick glasses. The yard-of-ale came into use in the 1680s and continued into the 19th

(Italian) A type of polychrome cane made by assembling a bundle of rods of different colors, and heating it until it is soft. The bundle is then attached to two pontils and elongated by drawing. At the same time, the bundle is twisted to produce a spiral pattern. Zanfirico, which is a synonym for

(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

Glass marbled with brown, blue, green, and yellow swirls in imitation of chalcedony and other banded semiprecious stones. Calcedonio Agate Vase with Cranes Flying Over the Sea

A type of decoration in the stems of 18th-century and later drinking glasses made by twisting columns of air.

When I hear music, it translates into color.—Toots Zynsky Toots Zynsky’s distinctive heat-formed  filet de verre  (glass thread) vessels enjoy a widespread popularity and deserved acclaim for their often extraordinary and always unique explorations in color. Defying categorization, her pieces

(Italian, “glass with threads”) A type of blown glass made with canes that form a pattern of parallel lines. vetro a filis vetro a file Wineglass

(Italian, “glass with a small network”) A type of blown glass made with canes organized in a crisscross pattern to form a fine net, which may contain tiny air traps. vetro a reticelo Reticellos Reticelo Retichello Reticello Goblet

(Italian, “glass with twists”) A type of blown glass made with canes that have been twisted to form spiral patterns. vetro a retortis retortolis retortole retortoles retortis retortie retorte Retortoli Retorti Footed Dish (vetro a retortoli)

(Italian, “lace glass”) A term loosely applied to various types of vetro a reticello. Vetro a reticello Dish (vetro a reticello)

A first-century A.D. Roman mold-blown drinking vessel inscribed in Greek with words meaning “Take the victory.” victory beakers victory-beaker victory-beakers Victory

(German, “wart beaker”) A heavy glass tumbler made of forest glass and decorated with prunts. It was produced in Germany in the 16th and 17th centuries. warzenbechers warzenbecker warzenbeckers Warzen becher Prunted Beaker

A defective object discarded during manufacture. Wasters are routinely recycled as cullet. wasters

A pitcher with matching tumblers, sometimes with a matching tray. water sets water-set 7-piece Toy Water Set

Changes on the surface of glass caused by chemical reaction with the environment. Weathering usually involves the leaching of alkali from the glass by water, leaving behind siliceous weathering products that are often laminar. whethering weathered Statuette of Venus

A process of decorating the surface of glass by the grinding action of a wheel, using disks of various sizes and materials (usually copper, but sometimes stone), and an abrasive in a grease or slurry applied to a wheel, as the engraver holds the object against the underside of the rotating wheel.

The technique of decorating glass in high relief by cutting or carving away part of the glass between the body of an object and its decoration (e.g., on a cage cup). undercut undercuts Cage Cup

(from Latin), pl. unguentaria. A term commonly applied to ancient Roman toilet bottles. It appears, however, that the term was “invented” in the 19th century, on analogy with unguentarius (perfume seller) and similar Latin words that the Romans used in connection with perfumes. unguentaria Toilet

Glass colored with uranium oxide. The earliest reference to uranium glass appears to date from 1817. It was made popular by Josef Riedel in and after 1834. See also Annagelb (which is yellow) and Annagrün (which is green). uranium glasses uranium-glass Cut Uranium Glass Vase

(French, “vermiculate”) design: A convoluted ground pattern resembling worm tracks. vermiculées vermiculee vermiculé vermicule

(French) A decorative technique in which gold or silver leaf is applied to the back side of a piece of glass, engraved, and protected by varnish, metal foil, or another piece of glass. The name is derived from the French mirror and picture framer Jean-Baptiste Glomy (d. 1786). Decoration of this

The process of applying trails of glass as decoration on the body, handle, or foot of a vessel. It is done by laying or winding softened threads on a glass object during manufacture. Combed decoration Cosmetic Bottle (Amphoriskos)