The dictionary of science and technical terms used in philosophy, literature, professions, commerce, arts, and trades / by W.M. Buchanan ; with supplement ; edited by James A. Smith.

Buchanan, W. M.

Date:: 1884

Credit: The dictionary of science and technical terms used in philosophy, literature, professions, commerce, arts, and trades / by W.M. Buchanan ; with supplement ; edited by James A. Smith. Source: Wellcome Collection.

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$Alu'mina, i one of the primitive Alu'mine, ) earths, which, as consti- tuting the plastic principle of all clays, loams and holes, was called argil, or the argillaceous earth, hut now being ob- tained in greatest purity from alum, it is called alumina. In its mixed state it is one of the most abundant substances in nature, but pure and unmixed it is one of the rarest. The sapphire and ruby are perhaps the purest native specimens of it: these gems are simply the clay crystal- lized and combined with small portions of colouring matter. To obtain it pure, it must be precipitated from alum by means of ammonia. Thus obtained, it is destitute of smell or taste, insoluble in water, but mixes with it readily: may be made into a ductile paste, and kneaded into regular forms. Alumina was deemed an elementary substance, till Sir H. Davy’s electro-chemical researches led to the knowledge that it is a metallic oxide, the metallic basis of which is called alu- minum, (q. v.). It consists of 52 91 alu- minum, and 47‘06 oxygen. Alu'minite, a mineral of a snow-white colour, dull, opaque, and having a fine earthy fracture. It is a native subsulpliate of alumina, and occurs chiefly in the al- luvial strata round Halle, in Saxony. Alu'minum, the metallic basis of alu- mina. It somewhat “ resembles pla- tinum in powder.” Sp. gr. 13'7. The experiments of Sir H. Davy first led to the belief that alumina is a metallic oxide, but it was Woeliler who first suc- ceeded in separating the metallic sub- stance. Alum-slate, 1 a bluish or greenish Alum-schist, j black mineral, contain- ing more or less iron pyrites mixed with coaly or bituminous matter. It occurs in the strata of brown coal, where the upper layers lie immediately under clay-beds. Prom this schist the greater portion of the alum manufactured in Britain is made. Mineralogists distinguish between com- mon and glossy alum-slate. Alum-stone, 1 Alum-stone is a mineral Alum-rock, j of a white colour, sometimes inclined to grey. It occurs in beds of a hard substance, characterised by numerous cavities, containing drusy crystallizations of basic alum. The beds in which the alum-stone occurs, is called alum-rock. Hungary yields large quan- tities. The alum-stone contains all the constituents of alum, being a siliceous subsulphate of alumina and potash: the alum-scliists contain only two of them. Clay and sulphur, convertible into sul- phate of alumina: the alkali must be added. Aluta (Lat. for tanned leather). Leather- stone ; a soft, pliable mineral, not lami- nated. Alve'ary, Lat. alvearium, of alveare, a bee-hive. The meatus auditorius externus, the hollow of the external ear, or bottom of the concha, where the wax is con- tained. Alve'olar, Lat. alveolaris. Appertaining to the alveoli or sockets of the teeth. Alve'olate, Lat. alveolatus. Having small cavities, so as to resemble a honey- comb. Alve'ole, Lat. alveolus. A little cavity. Technically : 1. A cell in a honey-comb, in a fossil, &c. 2. A socket in which a tooth is placed. 3. A marine fossil, of a conical figure, «vmposed of a number of cells like a honey-comb, joined by a tube of communication. Alve'olite, a marine fossil composed of numerous concentric beds, each formed by the union of hemispherical cells : the body itself is usually of a hemispherical shape. From alveolus, and Xi8o;- Only one spe- cies is known, and it occurs in the Port- land stone. Al'vine, Lat. alvinus. Appertaining to the belly (alvus): usually applied in rela- tion to the intestinal excretions. Al'vus (Lat.), the belly: used in ana- tomy. Alt'pon, the Globularia alypum of Lin. It is a drastic purgative. Name, from a,, not, and Xwrrv\, pain. Aly'sm, Lat. alysmus, of aXvaj, to be anxious. The inquietude which a patient exhibits under disease. Alys'sum, the generic name of the plant madivort, supposed to be a specific in cases of hydrophobia. Class tetradidynamia, order siliculosa. There are ten species, ail foreign. Name, from «, not, and Auer era, hydrophobia. A.M. stand for artium magister, master of arts, the second degree given by uni- versities and colleges, and called in some countries doctor of philosophy. Also for anno mundi, in the year of tlie world; and ante meridiem, before noon. A'ma, from Dan. aam, a vessel. Written also Hama. 1. In chxirch affairs, a vessel to contain the wine for the Eucharist. 2. A wine measure of indefinite size, as a cask, a pipe. Amaby'r, an old British word, signify- ing “ the price of virginity,” and express- ing a barbarous custom which formerly prevailed in England and Wales, being a sum of money paid to the lord when a maid was married within his lordship. Amacra'tic, 1A lens photographically Amasthe'nic. i perfect, or which unites all the chemical rays into one focus, may be called amacratic {ataa, together, and to;, power), or amasthenid (aStvoe, force). If this nomenclature be adopted, a diacratic or diasthenic medium will be one which transmits the chemical power$