Part 52

=AT'TAR.= See OTTO and VOLATILE OILS.

=ATTELETTES= (-l[)e]ts'). [Fr.] In _cookery_, small skewers, generally of silver, with ornamental heads. The term is also applied to small dishes (ENTRÉES, &c.) in which the articles are mounted on attelettes. Small fish, as smelts, are often served in this way. See AIGUILLETTE.

=ATTEN'UANT= (-[=u]-[)a]nt). _Syn._ ATTEN'UANS, L.; ATTÉNUANT, Fr.; VERDÜNNEND, Ger. That makes thin, or less dense or viscid; diluting. In _medicine_, applied to remedies (ATTEN'UANTS, SPANÆM'ICS) which are supposed to act by thinning, diluting, or impoverishing the blood.

=ATTENUA'TION.= _Syn._ ATTENUA'TIO, L.; ATTÉNUATION, Fr.; VERDÜNNUNG, Ger. A thinning or diminishing; a reducing in consistence. In _medicine_, see the adj. (_above_); in _brewing_, the decrease of the density of worts during fermentation, arising from the gradual conversion of their 'saccharine' (sugar) into alcohol. See BREWING, DISTILLATION, WORTS, &c.

=ATTRAC'TION.= [Eng., Fr.] _Syn._ ATTRAC'TIO, L.; ANZIEHUNG, Ger. The power that draws together matter and resists its separation. That force which attracts bodies towards the centre of the earth, and which keeps on its surface those that are movable, is called GRAVITY, or the attraction of gravitation. It is exerted at sensible, often at immense, distances, and determines the figure and motions of the planets and comets, and causes the descent of heavy bodies to the ground. This force it is which confers the property of weight upon matter.

That force which unites particles of the same kind of matter, so as to cause them to assume the condition of solid or liquid masses, _e.g._ particles of chalk to form a mass of chalk, particles of water to form a mass of water, is called COHESION, or the ATTRACTION OF COHESION. That force which binds together different substances without changing their properties, as when paint sticks to wood, ink to paper, &c., is called ADHESION, or the ATTRACTION OF ADHESION. CAPILLARY ATTRACTION is a modification of adhesion, and is characterised by being exerted between liquids and the internal surfaces of tubes and pervious bodies. The absorption of water by a sponge, the ascent of oil in the wick of a lamp, are examples of this power. The CHEMICAL FORCE or AFFINITY differs from all other kinds of attraction in being exerted between definite and constant quantities (atoms) of matter, usually of dissimilar natures, and producing combinations possessing properties different from those of their components. (See AFFINITY.) This force, as well as cohesion and adhesion, is exerted at distances so small as to be immeasurable.

The terms ELEC'TRIC ATTRACTION and MAGNET'IC ATTRACTION are employed in _physics_ to denote phenomena which we imperfectly understand, and which operate between bodies at sensible distances, and simulate those of the attraction of gravitation.

=ATTRI''TION= (tr[)i]sh'-[)u]n). [Eng., Fr.] _Syn._ ATTRI''TIO, L.; ABREIBUNG, AUFREIBUNG, Ger. In _mechanics_, the wearing away of parts by friction. In _medicine_, a graze, abrasion, or solution of continuity of the cuticle, or the act which causes it. In _surgery_, the crushing or tearing away of any exterior portion of the body by violence. See ABRASION, ANTI-ATTRITION, FRICTION, &c.

=AURANTIA'CEÆ= (-she-[=e]). [Lat.; DC.] The orange tribe. In _botany_, an extensive and important natural order of exogenous trees and shrubs, found exclusively in the temperate and tropical parts of the Old World, and unknown in a wild state in America. The fruit is pulpy, succulent, sub-acid, and eatable, and separated into cells by membranous partitions, and is covered with a leathery aromatic skin or rind. Some of the genera embrace plants of great beauty and utility. A few of the Indian species are climbers. The genus CIT'RUS, which includes the orange, lemon, citron, lime, bergamot, and shaddock, is that best known in Europe.

=AURAN''TIIN= (-she-[)i]n). _Syn._ HESPERIDIN; AURAN'TINE* (-t[)i]n), Eng., Fr.; AURANTII'NA, &c., L. The bitter principle of the peel of oranges and lemons.

_Prep._ The exterior or yellow peel of the Seville orange (carefully separated from the white matter, and air-dried) is steeped in hot water, and the filtered liquor gently evaporated to dryness.

_Prop._, _&c._ It possesses the bitter properties of the peel without any of its glutinosity or fragrance, and is said to agree better with delicate stomachs. It may be taken in water either with or without the addition of a little sugar or capillaire, or dissolved in wine.

=AU''RIC= (aw'- or awr'-). _Syn._ AURI'CUS, L. Of or relating to gold, or containing it, or formed from it.

=AURIF'EROUS.= _Syn._ AU''RIFER, AURIF'ERUS, L.; AURIFÈRE, Fr.; GOLDHALTIG, Ger. In, _mineralogy_, that yields or contains gold; as auriferous sand, a. quartz, &c.

=AURIPIGMEN'TUM[dagger].= [L.] Literally, paint of gold; appr., native orpiment. See ARSENIC.

=AURO-CHLO''RIDES= (kl[=o]re'-[=i]dz). Compounds of terchloride of gold with chlorides of other bases. They may be prepared by mixing the terchloride of gold with the chloride of the base, in atomic proportions, and setting aside the solution to crystallise.

_Prop._, _&c._ Most of the auro-chlorides crystallise in prisms, dissolve in both alcohol and water, have an orange or yellow colour, and are decomposed at a red heat.

=AURO-CY'ANIDES= ([)i]dz). In _chemistry_, compounds of cyanide of gold with cyanides of other bases. They may be formed in a similar manner to the auro-chlorides. Auro-cyanide of potassium is much used in electro-gilding.

=AURORA BOREALIS.= This luminous phenomenon, which is occasionally seen in our own country on clear frosty nights, and much more frequently and vividly by the dwellers in more northern latitudes, has been supposed to have an electrical origin, and to be occasioned by the passage of electricity through the rarefied strata of the upper regions of the atmosphere from the poles towards the equator. But physicists look upon this explanation as unsatisfactory, and inadequate to account for the effects produced. The hypothesis, however, seems to derive some support from the following fact:--

If one of Gassiot's vacuum tubes be brought near to a powerful electrical machine, both while the machine is in motion and for some time after, flashes of light may be seen passing from the wire at one end of the tube to the other extremity, which flashes bear a great resemblance to the auroral rays. The great doubt, however, is whether the conditions necessary to the production of the aurora are similar to those prevailing during this experiment, a doubt not lessened by the difficulty of satisfactorily accounting for the rarefied state of the atmosphere which is assumed to exist.

The forms which the aurora assumes are very varied and of great beauty; there appears, however, to be some general similarity in its aspect at the same locality. Its appearance is briefly as follows:--A dingy aspect in the heavens in a northernly direction is usually the precursor of the aurora; and this gradually becomes darker in colour, and assumes the form of a circular segment surrounded by a luminous arch, and resting at each end on the horizon. This dark segment presents the appearance of a thick cloud, and is frequently seen as such in the fading twilight, before the auroral light manifests itself. The density of this segment must, however, be very inconsiderable, as stars may sometimes be seen shining brightly through it.

This dark segment is bounded by a luminous arch of a blueish-white colour, which varies in breadth from 1 to 6 diameters of the moon, having the lower edge sharply defined, and the upper edge only when the breadth of the arch is small. This arch may be considered to be a part of a luminous ring, elevated at a considerable distance above the earth's surface and having its centre corresponding with some point near the north pole. The preceding description indicates the general features of the appearance of the aurora borealis; but several auroras have been described which presented striking peculiarities. Sometimes the phenomenon assumed the form of one or more curtains of light, depending from dingy clouds whose folds were agitated to and fro as if by the wind. Sometimes this curtain appeared to consist of separate ribbons of light, arranged side by side in groups of different lengths, and attaining their greatest brilliancy at the lower edges. In this country the aurora borealis seldom assumes the distinctness and brilliancy which characterise its appearance in northern latitudes, but the description thus given indicates the type to which such appearance of the meteor more or less approaches. During the winter that prevails in the northern hemispheres the inhabitants of the arctic zone are deprived for months together of the sun's light, and their long dreary night is relieved by the light emanating from this beautiful meteor, which shines with great frequency and brilliancy in those regions.

A remarkable connection has been observed between the aurora and the earth's magnetism, the magnetic needle showing great disturbance during a display of the aurora. The arches of the aurora most commonly traverse the sky at right angles to the magnetic meridian, though deviations from this direction are not rare. Sir J. Franklin found that the disturbance of the needle was not always proportionate to the agitation of the aurora, but was always greater when the quick motion and vivid light were observed to take place in a hazy atmosphere. The aurora is most frequent and vivid in high latitudes, towards either pole, but the meteor is not confined to these parts, as Dr Hooker states that one of the most brilliant displays he ever witnessed was under the tropical sky of India; and other observers have recorded instances of its appearance in the equatorial districts of the globe.

The attitude of the aurora varies considerably; there appears to be little doubt, however, that it frequently occurs at small elevations. Both Franklin and Parry record instances where it appeared below the level of the clouds, which they describe as having been hidden behind the masses of its light, and as reappearing when the meteor vanished. It would seem that there are two distinct kinds of aurora one dependent upon local causes, as in the cases last given, while in the other causes are probably cosmical, and the auroral effects are seen at very distant points of the earth's surface.

=AURORA POMADE.= For promoting the action of the skin. Cocoa butter with orris.

=AUTOG'ENOUS= (t[)o]j'-). _Syn._ AUTOGE''NEAL; AUTOG'ENUS (t[)o]j'). L. Self-generating or affecting; acting without the aid of foreign matter. In _anatomy_, &c., developed from distinct and independent centres; as parts or processes. Among _metallists_, it denotes a method of joining metals by fusing the parts in contact, by means of a flame of hydrogen, or of a mixture of hydrogen and common air, without the intervention of a fusible alloy or solder. Lead, and even ordinary hard solders, are, however, sometimes so employed, and the name, though improperly, retained.

=AUTOMAT'IC.= _Syn._ AUTOMATI'CUS, AUTOM'ATUS, L.; AUTOMATIQUE, Fr.; AUTOMATISCHE, Ger. Self-acting or self-moving, or that seems to be so; mechanical; of or resembling an automaton. In _physiology_, involuntary, applied to functions which are performed without the operation of the will; as the movements in respiration, the contractions and dilations of the heart, the persistent contraction of the sphincters, &c. In _mechanics_, &c., moving and acting from concealed machinery; also, as applied to _machinery_, self-regulating and directing, within the limits prescribed by its author, though moved by external power. To the last class belongs the self-acting machinery of our flax and cotton mills, our engineering establishments, &c.; in which the elemental powers are made to animate, as it were, millions of complex organs, infusing into forms of wood, iron, and brass, an agency resembling that of intelligent beings. The manufactures in which such machinery is employed are termed the AUTOMATIC ARTS.

=AUTOPSY.= Literally, personal observation or examination; ocular view. The term, however, is now applied, rather loosely, to a post-mortem investigation. A post-mortem may be performed with the object of endeavouring to ascertain the cause of death in a medico-legal inquiry, or in the furtherance of the study of pathology. It is also a preliminary to embalmment, and is sometimes had recourse to as a means of saving the child when a woman dies in full pregnancy.

In France no post-mortem examination is permitted to take place until at least 24 hours after death, this delay being enforced as a safeguard against the possibility of the body operated upon being still alive. In England no post-mortem can be made without the consent of the friends of the deceased, unless by warrant from a coroner; although in many public institutions this consent is dispensed with. Whenever, however, a prisoner dies in gaol an inquest and post-mortem are held on the body.

An autopsy is to be discouraged in cases where a person has died from infectious disease; but should the law require it to be undertaken, disinfectants both during and after the operation should be liberally had recourse to.

=AUTUMNAL FEVER.= This term is chiefly employed by American medical writers to designate typhoid fever, because of its prevalence in the autumn.

=AUXILION.= A packet of small plasters for the painless and radical cure of corns. Each plaster is to be worn for about a week, and then the horny pustule is to be removed with a sharp knife. The plaster is a compound of 1 part of resin plaster and 2 parts of lead plaster, and is likely to promote the removal and solution of the thick skin of the corns. (Hager.)

=AVA.= _Syn._ KAVA-KAVA. The native names of the root, a species of piper, the _piper methysticum_, cultivated in Tahiti, Hawaii, the Society and Tongan Islands, the natives of which make it into an intoxicating drink. It is said to have been used in France with excellent effect in gonorrh[oe]a; and a tincture of it has been strongly recommended both for external and internal administration in gout. "For medicinal purposes it is used in the form of infusion," a drachm of the scraped root being macerated in a quart of water for five minutes. Its action appears to vary with the amount taken; in small doses it is generally stated to act as a stimulant and tonic, but when taken in large doses it produces an intoxication which differs from that caused by alcohol, in being of a silent and drowsy nature accompanied by incoherent dreams" ('Pharmaceutical Journal,' August 19th, 1876, which consult for further information.')

=AVE'NA.= [L.] The oat; oats.

=AVE'NIN= (-n[)i]n). _Syn._ AVENA'INE* ([)a]v-e-) AVENI'NA, &c., L.; AVÉNINE, &c., Fr. A nitrogenous compound, analogous to, and probably identical with, casein, obtained from oats, and on which its nutritiveness chiefly depends.

_Prep._ The grain, reduced to the state of powder or meal, is washed on a sieve, and the milky liquid, after being allowed to deposit its starch, is heated to about 200° Fahr., to coagulate the albumen; when cold, acetic acid is added as long as a white powder falls, which is AVENIN; this is collected on a filter, drained, and dried by a gentle heat.

=AVEN'TURIN, Avant'urin= (-[=u]-r[)i]n; -v[)o]_ng_-t[=o][=o]--Knowles and Smart). [Eng. Fr.] A beautiful iridescent variety of rock crystal, minutely spangled throughout with yellow scales of mica (AVENTURIN, A. QUARTZ). A variety of felspar (A. FELSPAR) of somewhat similar appearance is found in the Continent and the Peninsula, of which the finer kinds are called A. ORIENTALE and PIERRE DE SOLEIL by the lapidaries. Both varieties are now imitated by the glass and porcelain manufacturers. See GLASS, GLAZE, PASTE, &c.

=A'VIARY= (-ve-). _Syn._ AVIA''RIUM, L.; VOLIÈRE, Fr.; VOGELHAUS, VOGELHECKE, Ger. A place for keeping birds; generally applied to an enclosed space or building in which birds are kept, or bred, on account of their rarity, plumage, or song; and not for food.

_Situa., &c._ For exotic birds, a place should be selected where the temperature can be maintained at a proper degree throughout the year, and which is well protected from the weather. This is commonly done by choosing a space attached to the summerhouse or hot-house. When the aviary is only intended for birds of climates similar to our own, any part of the open garden may be chosen, and a portion closed in, either with trellis-work or wire-work, or netting; care being taken to provide, in some easily accessible portion of it, full protection from vicissitudes of weather and season. Nor must cleanliness, and due ventilation and protection from foul air or noxious fumes, be left unattended to.

=AVIGNON' BERRIES= ([)a]v-veen-yo_ng_). French berries.

=AV'OIRDUPOIS'= ([)a]v-[)e]r-du-pois'). The common weight of 16 oz. or 7000 gr. to the lb., used in these realms for all kinds of goods, except jewelry and the precious metals, and medicines in dispensing, or as ordered in the 'British Pharmacop[oe]ia' of 1867.

=AX'IS.= [L., Eng., Fr.] _Syn._ AXE, Fr.; ACHSE, Ger. Primarily, that on or around which anything acts or performs; an axle or axle-tree. In _anatomy_, that on or around which any organ or part rests, gravitates, or centres. In _astronomy_, the diameter on or about which a celestial body revolves. In _botany_, part or parts about which particular organs are arranged; an imaginary line passing from the base to the apex of a pericarp &c. In _crystallography_, imaginary lines passing through the central points of a crystal, and about which the molecules or particles of matter composing it may be conceived to be symmetrically built up. In _geology_, the centre of a mountain-group. In _mechanics_, the straight line, real or imaginary, about which any body oscillates or revolves. See CRYSTAL, &c.

=AX'LE, Ax'le-tree= ([)a]ks'l). _Syn._ ESSIEU, Fr.; AXE (am rade), &c., Ger. In _mechanics_, the pin, rod, or material line, on which a wheel, &c., turns. See ANTI-ATTRITION, FRICTION, &c.

=AX'UNGE= (-[)u]nje). _Syn._ AXUN'GIA, L. _Primarily_, 'wheel-grease,' the lard or fat of an animal; restricted in _pharmacy_ to hog's lard.--AXUNGIA CURA'TA, A. PREPARA'TA, is prepared or washed hog's lard (which _see_).

=AYER'S PILLS.= Sold in long wooden boxes, each containing 25 pills, covered with sugar and starch, and composed of pepper, colocynth, gamboge, and aloes. (Hager.)

=AZADIRACHTA INDICA.= (Ind. Ph.) Nim or Margosa Tree. (Ind. Ph.) _Habitat._ Common throughout India; often cultivated in gardens. _Officinal parts._--1. The bark (_Azadirachtæ cortex_, Nim bark). It varies much in appearance, according to the size and age of the tree producing it. The bark from the trunk of a tree above three or four years of age is covered with a thick scaly epidermis, and varies in thickness from 1/4 to 1/2 inch. That from the smaller branches is smooth, of a dullish purple colour, marked by longitudinal lines of ash-coloured epidermis, from 1/8th to 1/12th of an inch apart. The inner layer of the bark, of a whitish colour in the fresh state, is powerfully bitter, far more so than the outer dark-coloured layer, which, however, possesses a greater amount of astringency. It contains a crystallisable principle (margosine) and an astringent principle (catechin).--2. The fresh leaves (_Azadirachtæ folia_, Nim leaves).--_Properties._ Bark astringent tonic and antiperiodic; leaves stimulant.--_Therapeutic uses._ In intermittent and other paroxysmal fevers, in general debility, and convalescence after febrile and other diseases, the bark has been employed with success. The leaves form a useful application to ulcers and skin diseases when a mild stimulant is required.--_Dose._ Of the powdered bark, a drachm three or four times a day.

_Preparations._ DECOCTION OF NIM BARK (Decoctum Azadirachtæ). Take of the inner layer of nim bark, bruised, 2 _oz._; water, a pint and a half. Boil for 15 minutes, and strain whilst hot.--_Dose._ As an antiperiodic, from 1-1/2 to 3 _fl. oz._, every second hour previous to an expected paroxysm. As a tonic, 1 or 2 _fl. oz._ twice or thrice daily. As this decoction soon decomposes in hot weather, it should be prepared fresh for use when required.

TINCTURE OF NIM BARK (_Tinctura Azadirachtæ_). Take of the inner layer of nim bark, bruised, 2-1/2 _oz._; proof spirit, 1 pint. Macerate for seven days in a closed vessel, with occasional agitation; strain, press, filter, and add sufficient proof spirit to make 1 pint. It may also be prepared by percolation in the same manner as Tincture of Calumba, q. v.--_Dose._ From 1/2 to 2 _fl. dr._ as a tonic.

POLTICE OF NIM LEAVES (Cataplasma Azadirachtæ). Take of fresh nim leaves a sufficiency; bruise and moisten with tepid water. A good stimulant application to indolent and ill-conditioned ulcers. Should it cause pain and irritation, as it sometimes does, equal parts of rice-flour and linseed-meal may be added. The bitter oil of the seeds is held in high repute by the natives as an anthelmintic, and as an external application in rheumatism. It is also said to be an insecticide.

=AZOERYTH'RYN= (-r[)i]th'-r[)i]n). A substance obtained, by Kane, from archil. It is insoluble in alcohol, ether, and water; but is very soluble in alkaline lyes, to which it imparts a port-wine colour.

=AZO'IC.= _Syn._ AZÖOT'IC; AZO'ICUS, AZÖOT'ICUS, &c., L. Lifeless; wholly destitute of organic life. In _geology_, &c., applied to strata which do not contain organic remains.

=AZOLIT'MIN= ([)a]z-o-l[)i]t'-m[)i]n). A dark-red substance obtained, by Kane, from litmus, of which it forms a large portion of the colouring matter. It is insoluble in alcohol, and in water unless alkalised.

=AZ'OTE*= ([)a]z'[=o]te; a'-z[=o]te). [Eng., Fr.] _Syn._ AZO'TUM*, L.; AZOT*, Ger. Nitrogen (because it is unfit for respiration, _i.e._ destroys life).

=AZOT'IC.= _Syn._ AZOT'ICUM, L.; AZOTIQUE, Fr.; AZOTISCH, Ger. Of or like azote, or containing it or formed from it; irrespirable; destructive to life.--AZOTIC ACID[dagger] is nitric acid; A. GAS[dagger], nitrogen.--AZO'TOUS ACID[dagger] was nitrous acid.

=AZ'OTISED= (-t[=i]zd). _Syn._ NITROGENISED, Containing azote or nitrogen; a common epithet of nitrogenous substances used as food.

=AZ'URE= ([)a]zh'-[=u]re; [=a]'zhure--Knowles, Smart, Walker). _Syn._ CÆRU'LEUM, L.; AZUR, Fr.; HELLBLAU, HIMMELBLAU, Ger. In _dyeing_ and _painting_, sky-blue; also the name of one or more pigments which possess this colour. See BLUE DYES, BLUE PIGMENTS, SMALTS, ULTRAMARINE, &c.

=AZ'URE-STONE.= Lapis lazuli.

=AZ'URITE= (-[=i]te). In _mineralogy_, lazulite; blue malachite; sometimes, lapis lazuli (the name being, unfortunately, very loosely applied by different writers).

=AZ'YMOUS[dagger]= (-e-m[)u]s). _Syn._ AZ'YMUS, L. Unleavened; unfermented; as sea-biscuit. Unleavened bread was formerly termed AZ'YME[dagger] (-e-me) and AZ'YMUS[dagger] by theologists.

=BAB'LAH.= The rind or shell of the fruit of _mimosa cineraria_. According to Dr Ure, it contains a considerable quantity of gallic acid, some tannin, a red colouring principle, and an azotised substance, and is the article imported from the East Indies and Senegal under the name of NEB-NEB.--Used as a cheap dye-stuff for various shades of drab and grey.

=BAC'CA= (b[)a]k'-[)a]). [L.; pl., bac'cæ, b[)a]k'-s[=e].] A berry.

=BACK.= [D., bak, a bowl or cistern.] _Syn._ BAC. In _brewing_, a large, open, flat reservoir or cistern; commonly that in which wort is cooled. In _distillation_, the vessel into which the wort is pumped from the coolers, in order to be 'worked' with yeast. The LIQUOR-BACK in a brewery, distillery, or rectifying house is the water reservoir or cistern.

=BACKS.= In the _leather trade_, the thickest and stoutest portion of the hide, used for sole-leather.