Part 61

Ar`gen*ta"li*um (?), n. [NL.; L. argentum silver + E. aluminium.] A (patented) alloy of aluminium and silver, with a density of about 2.9.

{ Ar*gen"ta*mine (?), n. Also - min }. [L. argentum silver + E. amine.] (Med.) A solution of silver phosphate in an aqueous solution of ethylene diamine, used as an antiseptic astringent and as a disinfectant.

Ar"gon (?), n. [NL., fr. Gr. &?;, neut. of &?; inactive; &?; priv. + &?; work.] (Chem.) A colorless, odorless gas occurring in the air (of which it constitutes 0.93 per cent by volume), in volcanic gases, etc.; -- so named on account of its inertness by Rayleigh and Ramsay, who prepared and examined it in 1894-95. Symbol, A; at. wt., 39.9. Argon is condensible to a colorless liquid boiling at -186.1° C. and to a solid melting at -189.6° C. It has a characteristic spectrum. No compounds of it are known, but there is physical evidence that its molecule is monatomic. Weight of one liter at 0° C. and 760 mm., 1.7828 g.

Ar"go*naut (?), n. One of those who went to California in search of gold shortly after it was discovered there in 1848. [U. S.] Bret Harte.

The "Argonauts of '49" were a strong, self- reliant, generous body of men.

D. S. Jordan.

A"ri*el (?), n. [Heb. ariël, perh. confused with E. aërial.] In the Cabala, a water spirit; in later folklore, a light and graceful spirit of the air.

In zoölogy, ariel is used adjectively of certain birds noted for their graceful flight; as, the ariel toucan; the ariel petrel.

Ar"il*lode (?), n. [Arillus + Gr. &?; form.] (Bot.) A false aril; an aril originating from the micropyle instead of from the funicle or chalaza of the ovule. The mace of the nutmeg is an arillode.

A*ris"to*type` (?), n. [Gr. &?; best + -type.] (Photog.) Orig., a printing-out process using paper coated with silver chloride in gelatin; now, any such process using silver salts in either collodion or gelatin; also, a print so made.

Ar*kose" (?), n. (Petrog) A sandstone derived from the disintegration of granite or gneiss, and characterized by feldspar fragments. -- Ar*kos"ic (#), a.

Ar"ma*ture (?), n. (Elec.) That part of a dynamo or electric generator or of an electric motor in which a current is induced by a relatively moving magnetic field. The armature usually consists of a series of coils or groups of insulated conductors surrounding a core of iron.

Ar"mored cruis"er. (Nav.) A man-of-war carrying a large coal supply, and more or less protected from the enemy's shot by iron or steel armor. There is no distinct and accepted classification distinguishing armored and protected cruisers from each other, except that the first have more or heavier armor than the second.

Army organization. The system by which a country raises, classifies, arranges, and equips its armed land forces. The usual divisions are: (1) A regular or active army, in which soldiers serve continuously with the colors and live in barracks or cantonments when not in the field; (2) the reserves of this army, in which the soldiers, while remaining constantly subject to a call to the colors, live at their homes, being summoned more or less frequently to report for instruction, drill, or maneuvers; and (3) one or more classes of soldiers organized largely for territorial defense, living at home and having only occasional periods of drill and instraction, who are variously called home reserves (as in the table below), second, third, etc., line of defense (the regular army and its reserves ordinarily constituting the first line of defense), territorial forces, or the like. In countries where conscription prevails a soldier is supposed to serve a given number of years. He is usually enrolled first in the regular army, then passes to its reserve, then into the home reserves, to serve until he reaches the age limit. It for any reason he is not enrolled in the regular army, he may begin his service in the army reserves or even the home reserves, but then serves the full number of years or up to the age limit. In equipment the organization of the army is into the three great arms of infantry, cavalry, and artillery, together with more or less numerous other branches, such as engineers, medical corps, etc., besides the staff organizations such as those of the pay and subsistence departments.

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{ ||Ar*naut" ||Ar*naout" } (?), n. [Turk. Arnaut, fr. NGr. &?;, for &?;.] An inhabitant of Albania and neighboring mountainous regions, specif. one serving as a soldier in the Turkish army.

Ar"oid (?), n. [Arum + - oid.] (Bot.) Any plant of the Arum family (Araceæ).

A*rol"la (*rl"l), n. [F. arolle.] (Bot.) The stone pine (Pinus Cembra).

||Ar"rha (?), n.; pl. Arrhæ (#). [L. Cf. Earnest.] (Law) Money or other valuable thing given to evidence a contract; a pledge or earnest.

||Ar*te`ri*o*scle*ro"sis (är*t`r**skl*r"ss), n. [Gr. 'arthri`a artery + sclerosis.] (Med.) Abnormal thickening and hardening of the walls of the arteries, esp. of the intima, occurring mostly in old age. -- Ar*te`ri*o*scle*rot"ic (#), a.

||Ar`thro*chon*dri"tis (?), n. [NL.] (Med.) Chondritis of a joint.

||Ar*throd"e*sis (?), n. [NL., fr. Gr. &?; joint + &?; a binding together.] (Surg.) Surgical fixation of joints.

Ar*throp"a*thy (?), n. [Gr. &?; joint + &?;, &?;, to suffer.] (Med.) Any disease of the joints.

Ar"thro*spore (?), n. [Gr. &?; joint + E. spore.] (Bacteriol.) A bacterial resting cell, - - formerly considered a spore, but now known to occur even in endosporous bacteria. -- Ar`thro*spor"ic (#), Ar*thros"po*rous (#), a.

Ar"thro*tome (?), n. [Gr. &?; joint + &?; to cut.] (Surg.) A strong scalpel used in the dissection of joints.

Ar*thu"ri*an (?), a. Of or pertaining to King Arthur or his knights. J. R. Symonds.

In magnitude, in interest, and as a literary origin, the Arthurian invention dwarfs all other things in the book.

Saintsbury.