Glass
Glass names 2 different subjects across the 6 encyclopedias on this shelf. Each is set out below. 1 of them is described by more than one encyclopedia.
Glass a well known hard
Described by 2 of the 6 encyclopedias.
Aiton's Encyclopedia (1910)
a well known hard, brittle, transparent material. The substances used in making glass vary considerably, but the essentials are three: first, silicon in the shape of pure, clean sand, crushed quartz, or flint; secondly, an alkali in the shape of a soda or a potash; and thirdly, lime in the form of chalk or limestone, or else one of the lead ores. It is not difficult to find materials quite satisfactory for beer bottles, pop bottles, and other articles that may be made of coarse or colored glass, but for clear white glass, it is important to use sand free from iron, lest it give a green or yellow tinge. In the manufacture of window glass, the materials are mixed together in a crucible or furnace, and put over an intense flame, until they are melted together. After a thorough mixing and refining, the liquid is allowed to cool until it becomes pasty. The glassblower then dips one end of a long tube into the pot and gathers a lump of the sticky metal which he proceeds to blow into a huge bubble, just as a boy would blow a soap bubble. By twirling his tube, and by swinging it in a vertical direction like the spoke of a wagon wheel, he draws his bubble out into a large, long, hollow cylinder. If at any time his glass becomes too hard to shape, the workman thrusts it for a moment into a fiery furnace called a " glory hole ." In order to have room to swing his pipe the blower stands on a plank laid across a deep pit. When the cylinder has taken the required form it is allowed to cool. The ends are opened and trimmed while yet plastic. The hardened cylinder is then slit along one side with a diamond and placed in an oven, slit uppermost. As the glass heats up the crack widens, and the cylinder opens up, settling finally on the floor of the oven in the shape of a flat sheet of glass. This sheet is then sent through an annealing furnace to harden. It is then laid on a table and cut into window panes of marketable sizes. A glassblower needs to be a man of strong muscles and powerful lungs. He is expected to blow about eighteen pounds of metal into a cylinder about a yard long and a foot in diameter, much larger than an ordinary joint of stovepipe. A skillful blower can form a great variety of glass articles with his pipe and other tools. Heavy tumblers, delicate wine glasses, lamp chimneys, and bottles are entirely within the limits of his art. A great many cheap glass articles are made of glass pressed into molds. An experienced eye can detect the difference readily. In cut glass the general form is given by blowing or pressing. The design is cut by workmen who hold the object against a swiftly revolving wheel of soft steel, copper, or sandstone, the cutting edge of which is fed with emery and water. The polishing is done on a wooden wheel fed with a polishing powder. Plate glass is made in a different way. The liquid glass is poured out on a flat iron casting table as large as the pane is desired to be, and provided with adjustable rims around its edge, which are raised or lowered to give the desired degree of thickness. A long, heavy roller resting on the rim is passed back and forth to prevent any unevenness in the surface. After the glass has cooled and the plate has been annealed in a fiery furnace, a process which seems necessary to prevent glass from snapping apart without apparent excuse, the plate is fastened to a horizontal table and ground off by iron rubbers fed with sand until it has lost nearly half its thickness. The sheet is then polished with leather or felt buffers fed with fine emery powder and putty powder. Plate glass does not have as hard a surface as the blown and annealed window glass; but larger, heavier panes are possible. It is used chiefly for show windows and mirrors. Rough plate, unground, is used for large skylights. The heavy glass used for flooring is also cast in this way. Colored glass is made by the addition of coloring material. The motley dark brown and black glassware lately on the market is made from iron slag. Green is produced by adding copperas or iron filings; yellow, by sulphur, charred horn, or silver; blue, by cobalt or copper; ruby, by copper or gold; milky glass, by tin or zinc. An idle story runs that glass making was discovered by Phoenician sailors who found that the seashore became coated with glass beneath their campfires. Glass articles have been found in the excavations of Nineveh, made perhaps in Tyre and Sidon in the early days of trade by caravan. Glass beads have been found in Egyptian mummy cases, certainly 3,000 years old. Rome acquired the art of glass making from the Egyptians and carried it to Constantinople. Venetian glassblowers were long celebrated, and are noted still, for the beauty and delicacy of their glass work. At the present day Bohemian glass work leads in quality, fineness, and delicacy. Pure glass is not acted upon by ordinary acids and chemicals. For this reason, workers in laboratories use test tubes, retorts, beakers, and thermometers of Bohemian glass almost exclusively. Extensive beds of sand suitable for glass are found near Aix-la-Chapelle, Germany, and Fontainbleau, France. Belgium, England, and Australia have excellent sand for the purpose. At present the glass sands of the United States are found chiefly in Berkshire County, Massachusetts, and in the Juanita Valley of Pennsylvania. Cheap, clean fuel of great heating power, free from smoke and soot, is found in Pennsylvania in the form of gas, oil, and coke, an advantage which has made Pittsburg and vicinity the chief glass-making center of the United States. There are extensive glass works at New Albany and Alexandria, Indiana. Natural gas is used for fuel. The largest gas furnace in the world is said to be in use at the latter city. It accommodates fifty pots or crucibles, and gives employment to 750 men. Mr. Irving Colburn of Franklin, Pennsylvania, has expended $200,000 in perfecting a glass-rolling machine to take the place of the gatherers, blowers, and flatteners. By means of this machine, put into operation in 1908, one man and two boys are able to accomplish the work of thirteen skilled mechanics. The device is 120 feet long. The bystander sees the cooling surface of a molten tank of glass drawn off between rollers. A sheet of glass of the required width and thickness may be seen traveling like a sheet of paper and falling continuously on a table at the rear where it is cut into six-foot lengths on a rotary cutting table. According to the last census the statistics of glass making in the United States are: Glass factories 399 Capital employed $89,389,151 Wage earners 63,969 Annual wages $37,288,148 Cost of materials $26,145,522 Annual production $79,607,998 See Mirrors; Windows; Sand
Collier's New Encyclopedia (1921)
a hard, brittle, transparent substance, formed by fusing fusing together together mixtures of the silicates of potash, soda, lime, magnesia, alumina, and lead in various proportions, according to the quality or kind of glass required. Flint glass is used in making table ware and many articles of domestic furniture and fittings. Crown and flint glass are combined in the manufacture of achromatic lenses. Plate glass is made by pouring it upon a table which has a marginal edge of a height equal to that designed for the thickness of the glass. A roller travels over the table, on the ledges, and flattening out the glass, which is thus made of equal thickness throughout. Toughened glass is made by heating till it is about to soften, and then plunging it into a bath of oil at a greatly lower temperature. Usually, a mixture temperaturstuallych chiefly of oily substances, tallow, wax, resin, and the like, is put in the bath; and some manufacturers who worked the process for a time dropped the newly made glass vessels, while still hot, into the oleaginous mixture, by which plan neither reheating nor anneal ing by the ordinary process is required. After the articles acquire the temperai ture of the bath, they are removed. Painted or stained glass is of two styles, enamel and mosaic glass. In enamel glass proper, certain fusible pigments are painted on a sheet of white glass, which is then fired, and the result is a picture the tints of which even in the high lights are not wholly transparent. A modification of this method produces its picture partly by enameling on white glass partly by the use of potmetal glass, the color of which is heightened or modified by the use of enamels. Mosaic glass is made from a design wherein the drawing is given and the colors indicated, which is the working drawing of the glass painted. From this working drawing a kind of map is made which gives the various pieces of the mosaic. The glazier cuts these pieces out from sheets of glass of various colors, and hands them back to the painter, who proceeds first to paint the leading lines with a solid opaque enamel, the coloring matter of which is an oxide of iron. This being done the pieces of glass stuck together temporarily (by are means of wax) on a glass easel, and the painter slightly shades his bold traced lines with the same opaque color; using sometimes washes, and sometimes hatching of lightly laid-on lines, as in a black and white drawing on paper. Sometimes both washes and hatching are used, and the washed shadows are stippled. In any case the object of the method of shading is to keep the shadows as clear, and to dull the glass as little as the explanation or expression of the subject will admit of. Two or three or more firings are necessary during the process of this painting. This being done, the glass goes back to the glazier's bench again, and he leads it up, and the window, after having been solidified by a stiff cement or putty rubbed into the leaf of the leads, has then only to be put in its place and strengthened by the due iron stay bars. Of the origin of glass manufacture nothing is known, but according to Egyptologists, the Egyptians made sham jewels of glass at least 5000 or 6000 b. c. In some of the most ancient tombs scarabs of glass have been found imitating rubies, emeralds, sapphires, and other precious stones. It is probable that the great center of the glass industry of medieval and more recent times, Venice, received its early impulse and lessons from Constantinople. The art began there with the beginning of the city in the 7th century A. D., and there was a marked improvement after the conquest of Constantinople in 1204, and in 1291 the establishments were removed to the island of Murano, the manufacturers forming a guild with a register of nobility and guarding their secret with the greatest jealousy. In 1436 their color glass came into note, and continued so till the close of the century; and in the 16th century lace patterns and mirrors were introduced. In the 15th and 16th centuries plain glass with tasteful ornaments in gilt and enamel; in the 16th, crackled lace and reticulated glass; and in the 17th century, variegated or marbled glasses were produced. The Venetian glass enjoyed for a long time the monopoly of commerce, and within recent years there has been a marked revival of the skill and enterprise of Venetian craftsmen. In Germany the oldest glass dates from the 16th century, and consists of goblets and tankards of white color, enameled with colored coats of arms and other devices, millefiori, and schmeltz glass. Engraved glass was first introduced by Casper Lehmann, at Prague, in 1609, under imperial protection, and continued by his pupil Schwanhard; and ruby glass by Kunckel in 1679. Glass is said to have been made in 1294 at Quinquengrone, in Normandy, and a common kind was made later in Dauphiné and Provence. In 1665 20 Venetian glass workers were brought by Colbert to Paris, where they set up the blowing of glass and the silvering of mirrors, the famous mirror hall in Versailles having been furnished by them. In 1688 an exclusive privilege of making large plates of glass by casting was conferred on Abraham Thevart. The name Thevart was assumed by a syndicate of capitalists formed to develop and work the invention of Louis Lucas de Nehon, who was the real inventor of plate glass and the founder of the Gobain works, one of the most extensive plate glass works in the world. In France oxide of lead flint glass was made at St. Cloud in 1784; another manufactory was subsequently established at St. Louis in 1790; and the St. Cloud establishment was removed to the vicinity of Mont Cenis, where it flourished till 1827. It is uncertain whether glass was made in England before the 16th century, as that mentioned may have been imported from Flanders or Venice. In 644 Benedict Biscop introduced makers of glass windows into Northumbria; but window glass was not in general use for windows till the 15th century. Attempts were made to establish glass works at Jamestown, Va., in 1608-1622; at Salem, Mass., in 1639-1640; in New York City before 1664; and in Pennsylvania before 1683. Subsequently works were established in 1780 at Temple, N. H.; in 1792 at Boston; and in 1797 at Pittsburgh. Plate glass was first made there in 1853, and it is also made at Baltimore and New York. Pressed glass was invented in the United States.
Glass CARTER, an American public official
Collier's New Encyclopedia (1921)
CARTER, an American public official; born at Lynchburg, Va., Jan. 4, 1858. He received his education in public and private schools in Lynchburg; mastered the printing trade, and entered CARTER GLASS the field of journalism through the road of the printing office, becoming owner of the "Daily News" and the "Daily Advance," morning and evening papers of Lynchburg, after eight years as a printer. In 1899 he entered politics as a member of the Virginia Senate; served successively in that office until 1902 when he became a member of the 57th Congress for the unexpired term of P. J. Otey. Re-elected to the 58th Congress, he continued to serve in C Congress until, in 1920, he was elected U. S. Senator from Virginia, having previously been appointed to the unexpired term of Thomas S. Martin, deceased. His most conspicuous public services include his connection with the national banking legislation, as co-sponsor of the Owen- Glass Bill which became law in 1912. He was Secretary of the Treasury from Dec. 1918-Nov. 1919, and was elected U. S. Senator for the term 1919-1925.
What Has Changed in the Last Century
When Aiton's wrote this in 1910 the making of window glass still turned on a man with "strong muscles and powerful lungs" blowing eighteen pounds of molten metal into a cylinder, and plate glass had to be ground and polished away to nearly half its thickness. Both trades are gone: machine drawing of sheet glass spread in the 1910s and 1920s, and Alastair Pilkington's float process, developed at Pilkington in the 1950s and in commercial production from 1959, now makes almost all the world's flat glass by floating the ribbon on molten tin, so that it emerges flat and needs no grinding at all. Bottles went the same way after Michael Owens's automatic bottle machine of 1903. The three essentials the entry lists — silica, alkali and lime — are still the basis of ordinary glass, but the borosilicate glass sold as Pyrex from 1915 displaced the Bohemian glassware the entry recommends for laboratories, and glass has since become a communications material: the low-loss optical fibre demonstrated at Corning in 1970 underlies the internet.
Written for this edition, 2026.