Page:The New International Encyclopædia 1st ed. v. 01.djvu/674

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ANNE.
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ANNEALING.

of the throne to her brother, the new ministers had quarrels among themselves which prevented its successful prosecution; their plans and intrigues became sufficiently known to alarm the nation, and to alienate many political supporters of the Government party. A dispute between Oxford and Mrs. Masham, carried on for hours in the Queen's presence and terminating in her de- mand for his instant resignation, seems to have brought on the attack of apoplexy of which she died, August 1, 1714. The Elector of Hanover succeeded her as George I. The principal event of her reign, the union of England and Scotland, in 1707, may be mentioned in its personal re- lation to herself, as she was the last sovereign who reigned over these as separate kingdoms, and the first sovereign styled "of Great Britain." Another important event was the War of the Spanish Succession, in which the Duke of Marl- borough won brilliant victories over the armies of Louis XIV. of France. Queen Anne was of middle size and comely, though not beautiful. She was virtuous, conscientious, and affectionate, more worthy of esteem as a woman than of admiration as a queen. Her reign is often mentioned as a period rendered illustrious by some of the greatest names, both in literature and science, which her country has ever produced; but literature and science owed little to her active encouragement. Consult: Burton, Reign of Queen Anne (London, 1880); Oldmixon, Life of Queen Anne (London, 1716); Ashton, Social Life in the Reign of Queen Anne (London, 1882); and Morris, The Age of Anne (New York, 1887).


ANNE, Sister. In the story of Bluebeard (q.v.), the sister of Fatima. While Fatima is awaiting the penalty of her disobedience, Anne, on the top of the tower, watches for the coming of their brothers to save them.


ANNEAL'ING (From M. Engl, anclen, 0. F. neeler, Fr. nieller, to enamel, from Lat. nigel- lus, blackish ) . The process by which glass and certain metals are heated and then slowly cooled to make them more tenacious and less brittle. The rationale of annealing has been most studied, perhaps, in connection with steel manufacturing. Important steel castings are nearly always annealed, and it is a common re- quirement for steel forgings. In drawing steel wire, annealing is necessary at frequent inter- vals, and it is a common practice to anneal steel plates for the best marine boiler work. The hardening and tempering of steel are analogous processes to annealing, there being a close interrelation between the three phenomena. Steel is hardened by sudden cooling from a high temperature, usually at or above red heat, by plunging it into oil, water, etc. To temper steel means in its specific sense to mitigate, or to moderate, the effects of previous hardening. It is usually performed by gently reheating the previously hardened steel to a much lower temperature than red heat and then cooling it, generally suddenly, but sometimes slowly. While tempering somewhat moderates the effects of previous hardening, annealing aims nearly completely to eliminate them. Annealing of steel is usually effected by slow cooling from a temperature at or above red heat. Thus steel is in its hardest and most brittle state when hardened; in its softest and toughest when annealed; and in an intermediate condition when tempered.

In hardening, the steel articles, if small, are heated in boxes or pans filled with charcoal dust, and placed in reverberatory furnaces. Larger ar- ticles are heated in the furnace proper, which is often made of a special shape to fit the form of the article, such, for instance, as a long gun tube. In general, the more rapid the cooling, the harder and more brittle is the steel. Mer- cury is the most rapid cooling agent, and water, rapeseed oil, tallow, and coal-tar follow next in the order named. Steel castings and forgings for guns, marine engine-shafts, and armor-plate, where strength is more important than hard- ness, are usually cooled in oil; while steel for cutting-tools, where extreme hardness is the im- portant thing, is ordinarily hardened in water.

In tempering hardened steel articles, they are slowly heated by contact with hot iron bars, plates or rings, on the surface of melted lead or other fusible metal, in hot sand, in burning char- coal, or in special furnaces, to a temperature of from 428° F. to 600° F. The temperature re- quired for razors is from 446° F. to 469° F.; for shears and scissors, 491° F.; for woodwork- ing tools, 531° F.; for swords and coiled springs, 550° F.; for handsaws, 600° F. The heated ar- ticle is cooled by plunging it into a bath of water or oil.

In annealing, the article is heated imiformly in a furnace, without direct contact with the flames, to the temperature generally of bright cherry red. The common method of cooling is to withdraw the fire from the furnace and to close all apertures, allowing the furnace slowlj- to cool down. Cooling is sometimes accomplish- ed by burying the heated article in ashes, lime, or other slow conductors of heat, and allowing it to become cool by the radiation of its heat. Boiler and ship plates are often cooled by sim- ply withdrawing them from the furnace and throwing them on the mill floor to cool by ra- diation. When medals are repeatedly struck by the die-stamper, the gold or other metal, by the concussion, becomes brittle, and requires to be heated and annealed at intervals. Annealing is necessary in gold-beating and in rolling, ham- mering, and stamping sheet-metals generally. Ar- ticles of tin, lead, and zinc, which are metals with a low melting temperature, are annealed in boil- ing water, which is allowed to cool with the ar- ticle immersed. Malleable iron is cast-iron an- nealed by being covered with powdered hematite ore and heated and then slowly cooled.

In the making of glass vessels by the glass-blower (see Glass), they are of course quickly reduced in temperature while the fused glass is being molded into the desired shape. The atoms of the glass thus rapidly compelled to assume a permanent position do not seem to be properly and firmly arranged together, and the vessel is very liable to be broken, either by a slight but smart blow, or a sudden increase or decrease in temperature. This brittleness is very observable in the lacrimæ vitræ, or glass tears, known as Prince Rupert's drops, obtained by allowing molten glass to fall into water, when the glass forms pear-shaped drops, which are so brittle that if they be scratched with a file or the end be broken off the whole bursts asunder and falls down into a fine powder of glass. The same brittleness is exhibited in Bologna jars, or vials, which are small and very thick, and yet, if a minute angular fragment of any hard substance be dropped into the jar, the latter flies to pieces.

In the annealing of glass vessels, they are ar-