GLASS.–1. Venetian wine-glass. 2. Moulded glass Roman cup. 3. Portiand vase. Ground plan of tank furnace. 9. Section of tank furnace, showing reverberating ci Diagram of round furnace. 13. Evolution of a sheet of cylinder-glass 14. Venetian

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Pressing machine. 5. Venetian glass. 6. Plate-glass crucible. 7. "Monkey pot.' hambers. 10. Diagram of square furnace. II. Evolution of a table of crown-glass. mosaic pitcher. 15, 16. Lion's head, with inscription showing prenomen of Nuantef IV.

another workman with a "punty," or solid iron rod, attaches a small cup of warm glass to the bullion point, and the blower detaches his pipe by touching the neck of the flattened globe with a cold iron and quickly striking it. The punty-man carries it off with a small hole where it left the blow-pipe, and heating it in the furnace and revolving it, the opening enlarges wider and wider until it becomes the "crown," which named it, and at last whirls out into a flat disk or "table." This is kept incessantly turning till it cools enough to be laid on a support, where it is clipped by shears from the rod, and sent to the annealing oven. The diameter of such a plate varies from a few ins., like those made in colored glass for fancy windows, to 6 ft. But the square panes cut from it are always small, as the round lump in the center, the "bullion point," or "bull's-eye," must be omitted, though these have lately become decorations for artistic houses.

Plate-glass, the pride of France, Belgium, and England, has lately been made in this country in immense quantities. It is composed like sheet and crown-glass, but is melted in vast open kettles (sometimes holding 2 tons) resting upon frames behind fire-clay doors. After the long fusion is perfect the door is thrown open and the kettle is seized by an immense fork mounted on truck, and carried bodily, like a captured fiery star, to the casting-table, where it is hoisted by a crane and poured in a golden volcanic mass over the iron bed. A heavy roller passes over it, spreading the glass out in a uriform thickness determined by the height of the strips on either side of the table. Instantly it is rolled into the annealing oven for a tempering of several days. It comes out rough and dull, and in that condition is suited only to skylights and floors. To be polished it is fastened by plaster of Paris to a large rotary platform which revolves so that the entire surface is covered at each rotation by the disks of grinding machines which rub it with sand, then with emery, and last with rouge, first on one side, tlien on the other, till 40 per cent. of its thickness is removed, and it remains a shining sheet from one quarter to three-eighths of an inch thick. "Rolled plate" is cast upon an engraved table, which gives the impressions of fluted lines or fancy patterns in a translucent body of glass adapted to panels, partitions, etc. The casting-table, formerly made of bronze, is one huge piece of thick cast-iron. At Creighton, Pa., is the largest plate-glass establishment in the world, with a casting-house 65x150 ft., 4 times as large as the famous St. Gobain Halle in France, and nearly twice as large as the great British works at Ravenhead. The 2 casting-tables at Creighton are 7 ins. thick, 19 ft. long, and 14 ft. wide. They run on tracks to every furnace and oven, and produce 100,000 sq. ft. of glass every month. 3,000,000 bush. of sand dredged from the Alleghany are used every year for polishing, and natural gas takes the place of 3000 bush. of coal daily. But the largest plate ever made was from the St. Gobain company, and measured 214x134 ft.

Green-glass, or "bottle-glass," is the coarsest form, made from roughest materials, and is either green from the iron impurities or amber from the added coal dust. This is the simplest branch of glass-work. In America it is most extensively conducted near Philadelphia, as much of the sand of southern New Jersey is fine enough for this pur pose. The bottle-blower gathers the molten glass on his blow-pipe, in the quantity desired for his bottle, or jar, or demijohn, puffs a bubble into it, drops the inflated lump into an iron mold, which is closed together over it by a small boy, and blows the glass into its permanent shape with the lettering or trade-mark which was cut in the mold. The jagged mouth is then rounded in the " glory-hole," and the bottle goes to the "leer." Flint-glass broadly includes all the myriad forms of glass except window panes and dark bottles. The lead which the true flint-glass alone contains gives it a characteristic brilliancy and weight. The pure English flint is the French "crystal." It rings like metal, is heavier than any other glass, and shines as none did before its English invention. It is the choicest material for table and cut ware, for optical glass, and for the best blown and pressed ware that fills the household. An extra proportion of lead makes it "strass," from which artificial gems are made. The "lime-flint" of Bohemia and this country, substituting lime for lead, has a lighter weight and a luster approaching “lead flint," but it does not equal its royal superior. From this the ordinary utensils are made. A flint-glass establishment is the most fascinating of glass-houses, as it generally includes blowing, molding, and pressing, and is a spectacle of surprises. The heart of the building is a colossal chimney, about which are encircled from 8 to 12 "monkey pots," containing often several colors of molten " metal," as the fluid glass is called. Each glory-hole" is the center of a special kind of glass-bottles, chimneys, shades, etc., and at one side is the annealing tunnel. The apparent confusion of the silent, busy throng of men, youths, and boys is explained by their method of working. The work is entirely by the piece, and a group of 4 constitutes a "shop"-the blower, or finisher (the masterworkman), the gatherer (a young apprentice), and 2 boys. Each "shop" works independently of the rest of the establishment, under the general superintendent, and is paid by a schedule uniform throughout the trade for the number of pieces made, the blower getting the lion's share, the gatherer next, and the boys 30 cts. a day. Only by passing through these stages can the glass-makers' trade be learned. Trade-unions control the industry, severely limiting the number of apprentices admitted to their craft, dictating the scale of wages, refusing to work in July and August, operating strikes more successfully than any other tradesmen, because of the long service necessary for mastering their skill, and holding a close organization very like their trade-ancestors of old Venice. Under this system the best flint-glass workers are second only to the kings of the craft, the