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and the thread used by the Indians in sewing their birch-bark canoes is made from the roots of the white spruce.
Firdausi (fer-doo'se), Abul Kasim Man= sur, was the first and chief of modern Persian poets. The date of his birth is uncertain; he died in 1020 A. D. His great epic was the Shah Namdh or Book of Kings, upon which he worked for 35 years. The poem traces the fortunes of Iran, even from the time of the legendary kings, including the great Jamshid, who in the golden age reigned 500 years. The chronicle or, rather, epic closes with the fall of Persia before Islam. The poem was presented to Mahmud of Ghazni, but so petty was his reward that Firdausi wrote a bitter satire upon the monarch, and fled the country. A work of his old age is a poem upon Joseph and Potiphar's wife, as told in the Koran.
Fire=Damp is the miner's term applied to coal-gas when it issues from crevices in coal mines. The issue of the gas can sometimes be heard,, and it can be lighted. When it has from a quarter to a sixteenth part of air, it will explode, producing disasters that are too well-known in the history of mines. The explosion stirs up the coal-dust, and as each particle is fired the result is like the firing of grains of gunpowder,
Fire=Engine, a machine for the purpose of throwing water to extinguish fires. Machines for this purpose were employed by the Romans, as Pliny speaks of them, and so does Hero of Alexandria. There are accounts of instruments for fires being used in Augsburg in 1581 and in Nuremberg in 1657. By 1730 Newsham, in London, had made successful fire-engines; the first used in the United States (in 1731) were of his make. The simplest engine consists of a force-pump and a cistern for water. In the larger engines there is no cistern; the suction-pipe is carried directly to the water-supply. The first fire-engine in which steam was used was that of Braith-waite in 1829; Ericsson made a similar one in New York in 1840. The heaviest American engine, with water in the boiler and men on the engine, weighs over five tons. Chemical fire-engines are used to extinguish fires in small spaces; they depend on the rapid production of carbonic-acid gas, which is an enemy to all kinds of combustion. See Roper's Handbook of Modern Steam Fire-Engines.
Fire=Extinguisher, a term generally applied to a number of chemical agents, which extinguish fires by forming carbonic-acid gas. Fire-extinguishers are so made that they nlay be carried on the back and their stream directed by the hand.
Fire'fly, an insect capable of emitting light from some part of its body. These insects light marshes and wet meadows, the "banks of streams and ponds, and frequently
are very abundant. Those of tropical countries are most brilliant. In tropical America several are confined in a cage to give light. For the most part they are soft-bodied beetles of small or medium size, and fly at night. The luminous spots are yellowish in daylight. These are located on several joints of the lower side of the abdomen, and are richly provided with air-tubes. It is believed that the bright light is due to oxidation of the contents of the cells in the luminous patches. At any rate, phosphorus has nothing to do with it. In the United States they usually are called lightning-bugs. In Europe there are certain kinds in which the female is without wings, and has luminous patches on the abdomen. These and larvae that are luminous are called glow-worms.
Fire'proof ing. The word fireproofmg may mean the ways of so constructing buildings, safe-deposit vaults etc. as to make them capable of resisting the action of fire, or it may mean the coating of such combustible materials as wood and textile-fabrics, making them as fireproof as possible.
The means used to make buildings fireproof is, in general, to avoid as far as possible in their construction the use of combustible material, particularly wood; stone, brick, iron and cement being largely substituted for it. Of course most so-called fireproof constructions are only relatively so. If wood is carefully coated with a solution of silicate of soda, it will usually resist a high degree of heat without undergoing serious injury. A 20% solution of tungstite of soda is much used for making linen or cotton-materials fireproof. The textile is steeped in the solution and then dried. Different kinds of solution are used, varying with the different kinds of materials to be rendered fireproof. Some of the solutions used are apt partly to destroy the fabric. Fireproofmg of this nature is extensively used for the canvas-material from which the stage-scenery used in t eaters is constructed. If this scenery is not made fireproof, there is danger of great disaster, as theatrical contrivances are often such as easily to start a blaze. There are some
Eaints that are claimed to make wood reproof. These often contain sodium silicate and zinc chloride.
Fire'works. The art of making fireworks is called pyrotechny. They are made of some explosive material, of different colors and shapes, and used usually for amusement, though the rocket has been used for a signal in war. The powder generally used in fireworks is made on the same principle as gunpowder, and (besides the powder) niter, sulphur and charcoal are the main ingredients. Iron or steel-filings brighten the fire; zinc-filings give it a fine blue color; copper-filings give it a greenish tint. Yellow is produced by
