Page:The New International Encyclopædia 1st ed. v. 01.djvu/487

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ALTRICES.
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ALUMINA.

ALTRI'CES (Lat. nom. pl. of altrix, a female nourisher). A term used in ornithology (opposed to Precoces) to designate birds whose young are hatched in a helpless condition and require the care of the parent birds. Such birds usually build some sort of nest, where the young remain for some time after hatching. The young are usually naked when hatched. Nearly all land birds (except most game birds), and some water birds, as herons, pelicans, etc., are altricial. See Bird, and Nidification.


ALTRINCHAM. .nl'trini-flm. A market town of Cheshire, England, on Bowden Downs, miles southwest of Manchester (Map: England, D 3). ]t is situated on two railway lines and near the Bridgewater Canal, which has contributed greatly to its prosperity. It is a very neat and clean town, and on account of the salubrity of the air is a favorite residence of many of the merchants of Manchester. It has manufactures of artificial manures, cotton goods, and an iron foundry; but the chief employment of its inhabitants is the raising of fruits and vegetables for the market of Manchester. Altrincham was a prosperous town in the time of Edward I., from whom it received many privileges. Pop., 1891, 12,400; 1901, 16,800.


ALTRUISM, al'troo-iz'm (Ital. altrui, of, to, or for others, from Lat, alter, another). A word first coined in French by Comte (altruisme), and introduced by his Positivist followers into English as the antonym of egoism or selfishness. It signifies consideration for others and a due regard for their feelings and interests. Altruism is regarded by Positivists as the crowning virtue, in the exercise of which the perfected individual will find not only his duty but his chief pleasure. The word is now used far beyond the circle of Positivists, sometimes quite loosely in the sense of action resulting in the welfare of others, whatever might be the motive: sometimes more strictly in the sense of conduct motived by the desire for this welfare. It is only in this stricter application that the word has any significance for ethics. One of the most important problems of ethics is that concerning the relations between one's own interests and those of others, in so far as these interests enter as motives into conduct. There are two rival issues to the question. One school maintains that self-sacrifice is the supreme moral principle, the other champions self-assertion. This difference gives occasion to another use of the terms altruism and egoism. The view that altruism is the highest moral motive is itself called altruism, just as the view that acknowledges the primacy of egoism among moral motives is itself called egoism. For the criticism of these two views and for bibliography, see Ethics; Hedonism, and Utilitarianism.


ALTRUISTS, Society of. See Communistic Societies.


ALTSCHUL, alt'shool, Elias (1812-65), An Austrian physician of Jewish extraction. He was born at Prague, and studied medicine, graduating at the University of Vienna in 1832. He became professor of medicine at the University of Prague in 1848, and in 1853 founded the first homeopathic magazine in Austria, under the title of Monatsschrift für Theoretische und Praktische Homoöpathie. He introduced homeopathy at the University, His principal works are: Dictionnaire de médecine ocularire (Vienna, 1856, 2 volumes); Lehrbuch der Physiologischen Pharmacodynamik (Prague, 1850-52); Das therapeutische Polaritätsgesetz (Prague, 1852).


ALTWASSER, iilt'viis-er, A town of Silesia, Prussia, 40 miles southwest of Breslau, It has coal mining industries and manufactures of ma- chinery, porcelain, and mirrors. Pop.. lUOO, 12,700'.


ALT-ZABRZE, alt-zab'zhe. See Zabrze.


AL'UM (Lat. alumen, of unknown origin). A double salt consisting of a sulphate or selenate of the monovalent element or radicle, and a sulphate or selenate of a sesquioxide, that crystallizes in the isometric system with twenty-four molecules of water. The principal alums of commerce contain potassium, ammonium, or sodium, and the sesquioxide of aluminum.

Potassium alum is a white, astringent, saline compound, found native as kalinite. It is made by calcining carbonaceous shales, the residue from which is digested with sulphuric acid, yielding aluminum sulphate; to this potassium sulphate is then added, the resulting crystals constituting the alum. Another method consists in dissolving the alumina derived from the minerals cryolite or bauxite in sulphuric acid and treating the solution with potash or ammonia.

Ammonium alum is found native as tschermigite, and is artificially made by combining ammonium sulphate with aluminum sulphate as previously described. The low cost of ammonium sulphate, obtained as a by-product in the manufacture of illuminating gas, has led to the substitution of this alum in commerce for potassium alum. The properties of the ammonium and potassium alums are similar, though the ammonium compound is less soluble in water.

Sodium alum is found native as mendozite, and is made by the combination of sodium sulphate with aluminum sulphate.

Alum is used as mordant in dyeing, to clarify liquors of various kinds and especially water, to harden tallow, fats, and gypsum in the tanning of leather; the ammonium alum is used in the manufacture of baking powders. A potassium chromium sulphate, called chrome alum, and an iron aluminum sulphate called iron alum, are also used in the arts. Consult J. Gardner, Acetic Acid, Vinegar, Alum, Ammonia, etc. (Philadelphia, 1885).


ALU'MINA (from alum). Aluminum oxide, the most abundant of the earths. It is found native, nearly pure as corundum; with minute quantities of metallic oxides, as ruby, sapphire, Oriental amethyst, Oriental emerald, and Oriental topaz; and less pure as emery. It is also found in combination with silica, as in many of the minerals of the feldspar group, as well as in certain igneous rocks.

Alumina is known in two forms: A white, soft, pulverulent variety, and a colorless crystalline variety. It may be prepared in a pure state by heating potash alum with a solution of ammonium carbonate; the resulting aluminum hydrate is well washed, dried, and ignited, the residue being pure alumina. A comparatively pure alumina may also be obtained by heating ammonium alum until its volatile constituents are driven off. When alumina is precipitated from a solution containing some coloring matter, such as logwood, it carries down the color with the flocculent precipitate, forming colored insoluble salts called lakes. It is this property that has led to its extensive use as a mordant