union of acetic acid with ammonia as its base, and consisting of 1 atom of acetic acid=51; 1 atom of ammonia=17; 7 atoms of water = 63; atomic weight, 131.-Bicarbonate of ammonia, 2 atoms of carbonic acid =54; 1 atom of ammonia = 17; 2 atoms of water = 18; atomic weight, 86.-Carbonate of ammonia, 1 atom of carbonic acid=22; 1 atom of ammonia=17; atomic weight, 39.-Mu riate of ammonia, 1 atom of muriatic acid=37; 1 atom of ammonia == 17; atomic weight, 54.-Nitrate of ammonia, I atom of nitric acid= 54; I atom of ammonia = 17; 1 atom of water=9; atomic weight, 80.Oxalic of ammonia, 1 atom of oxalic acid=36; 1 atom of ammonia = 17; 2 atoms of water=18; atomic weight, 71.-Sesquicarbonate of ammonia, 3 atoms of carbonic acid=66; 2 atoms of ammonia=34; 2 atoms of water=18; atomic weight, 118.-Sulphate of ammonia, 1 atom of sulphuric acid=40; 1 atom of ammonia =17; 2 atoms of water = 18; atomic weight, 75.

Ammoniacum, a gum resin, obtained from the Dorema ammoniacum, from which it naturally exudes. Its varieties are lapis ammoniacus, in lumps, and gutta ammoniace, in drops. Am'monites (so called from the ram's horn on the head of the Libyan deity Ammon), in paleontology, an extinct order of molluscous animals, curved like a coiled snake, which are found in great abundance and variety in the secondary strata of the earth's

crust.

Amphib'ium (Gr. amphi, and bios life), that which lives in two elements, as in air and water. Am'phicome (Gr. amphi, and kome hair), a kind of figured stone, anciently used in divination.

Amphid (Gr.), an epithet applied to compounds consisting of acids and bases, as distinguished from haloid compounds.

Amphihexahe'dral (Gr. amphi, and hexahedral six-sided), a term applied to crystals whose faces, counted in two different directions, give two hexahedral outlines.

Am'phipods (Gr. amphi, and podes feet), in zoology, an order of Crustacea, with feet for both swimming and walking. Amphipros'tyle (Gr. amphi, and stylos a column), in architecture, an edifice having a portico or equal number of columns at each end, and thus presenting two fronts, but without columns at the sides or flanks. Amphi'scians (Gr. amphi, and skia a shadow), the inhabitants of the tropics whose shadows in one part of the year extend to the north and in the other to the south. Am'phitrite (Gr.), in astronomy, the name of one of the recently-discovered planets, first observed in 1854. Its mean distance from the sun is 243,530,000 of miles, and the time of its periodical revolution is four years and thirty days.

Amphod'elite, a reddish crystallized mineral from Finland.-Dana. Amplex'us (Lat. embrace), a term applied to corals of a cylindrical shape, which are divided by transverse septa into numerous chambers that embrace each other with reflected margins.

Ampulla (Lat.), in the arts, a globularshaped bottle, with a narrow neck, chiefly used as household ornaments. -In botany, applied to a leaf in which the petiole is dilated and hollowed out in the shape of a hollow vessel, open at the upper end. Ampulla'ria (Lat.), in malacology, a genus of spiral univalve Molluscs, which are found in the ponds and rivers of S. America, Africa, and India.

Am'ula (Lat.), in architecture and sculp

ture, an ornamented vase, usually made of marble or bronze, and found in temples and public edifices. Amygdaleæ (Gr. almonds), a nat. order of polypetalous exogens, of which Amygdalus, the almond trec, is the type. It is distinguished by its producing the kind of fruit called a drupe, as in the peach, nectarine, plum, cherry, almond, apricot, prune, damson, all of which belong to this order. Another of its characteristics is, that the leaves of this species yield prussic acid; the stamens are numerous, and rise from the orifice of a tubular calyx.-Amygdala amara are the kernels of a variety of Amygdalus communis, or bitter almond.Amygdala dulcis is a variety of the Amygdalus, the sweet almond, chiefly composed of fixed oil.-Amygdala oleum is the oil extracted from the kernels of both varieties of almonds. Amyg'daline (Gr. amygdalus), in chemistry, a crystalline principle contained in the bitter almond.-Amygdalinic acid is an acid obtained from amygdaline.

Amygdaloid (Gr. like an almond), in geology, a variety of trap rock, resembling almonds, generally vesicular, with embedded round or almond-shaped minerals, such as agate, calcareous spar, calcedony, jasper, or zeolites. Amygdalite is the name of the almond-stone.

Am'ylate (Lat. starch), in chemistry, a compound of starch with a base.Amylic acid is a volatile acid obtained from starch.-Amyline is the fecula or crystallized starch of wheat.

Am'ylum (Lat. starch), in pharmacy, a preparation of starch obtained by diffusing flour through a large quantity of water, by which the saccharine and mucilaginous matters are dissolved-the fibrous parts floating on the surface, while the fecula is allowed to subside. It consists of oxygen, carbon, and hydrogen. Amyrid'e (Gr. myrrha, myrrh, the type of the order), a nat. order of ornamental trees; the leaves, bark, and fruit of which abound in odoriferous resins and gums.

Ana (Gr. again), in pharmacy, a term used by physicians, importing the like quantity, as honey and wine, ana, ii; that is, honey and wine, each two ounces.

A'nabas (Gr. to ascend), a genus of fishes belonging to the Perch family, remarkable for the power they possess of quitting their native element, and making their way on land. Anabe'næ (Gr. to ascend), a family of

Saurians, which, like the chameleon, are in the habit of climbing trees. An'ableps (Gr. to look up), a genus of fishes, of the tribe Cyprinidae, which inhabit the rivers of Guiana. Anabro'sis (Gr.corrosion), in pathology, a wasting away of any portion of the body.

Anacamp'tics (Gr. to bend back), in optics, the science of reflected light; Catoptrics. An anacamptic sound, a sound that produces an echo; an anacamptic hill, a hill that sends back an echo.

Anacan'thus (Gr. ana, and akanthus a spine), a genus of fishes, the skate, which have neither fins nor spine on the tail.

Anacardiaceae (Gr. ana, and kardia the heart), in botany, a natural order of polypetalous exogens, which contains among its genera the cashew (which produces a black caustic oil), the sumach, the mango, and the pistachia.

Anacar'dium (Gr. ana, and kardia the heart), a genus of plants to which

belongs the cashew-nut, and so called from its being heart-shaped. Anacathar'tics (Gr. ana, and katharos pure), in pharmacy, any medicine that operates upwards; a cough attended with expectoration. Anach'ronism (Gr. ana, and chronos time), any error in chronology, or the computation of time, by which historic events are misplaced. Anaclas'tic (Gr. to bend back or refract), in optics, breaking the rectilinear course of light.-Anaclastic glasses are sonorous glasses or phials, which emit a vehement noise by means of the human breath. Anaclas'tics (Gr.ana, and klao to break), that branch of optics which treats of the reflection of light; Dioptrics. Anacli'sis (Gr. ana, and klino to lie down), in pathology, the attitude of a sick person in bed, which affords important indications in various

cases.

Anacon'da, in herpetology, a species of boa or large serpent of Ceylon, and other parts of Asia. Anacyc'lus (Gr. without a circlet of flowers), a genus of composite plants, the ring-flower.

Ana'mia (Gr. ana, and haima blood), in pathology, a deficiency of blood. Anæsthe'sia (Gr. without feeling), in pathology, deprivation of the sense of touch or feeling. Anesthetic (Gr. a priv. and aisthesis feeling), tending to deprive of sensation.

Anagal'lis (Gr. dispelling grief, a genus of plants with wheel-shaped

corollas and a capsule opening in two halves, the one fitting into the other; the pimpernel, or poor man's weather-glass, which opens in the morning, and closes in the afternoon; in wet weather the petals remain closed.

An'aglyph (Gr. ana, and glypho to engrave), anything in relief; an ornamental piece of sculpture, engraving, chasing, or embossing.

An'agogy (Gr.), in pathology, the rejection of blood from the lungs. Anal'cime (Gr. weakness), in mineralogy, a variety of zeolite, occurring usually in trap rocks; when rubbed, it becomes weakly electric, whence the name; it consists of silica, alumina, soda, and water; sp. gr. 3.

Anal'cipus (Gr. weak-footed), a genus of birds, of the family Dicrurinæ, or Drongo Shrikes..

Analep'sis (Gr. a recovering), in pathology, restoration from sickness to health.-Analeptic is a medicine which tends to restore the body to health and vigour.

An'alogue (Gr. resemblance), in palæontology, applied to an animal or plant in the fossil state, which bears a strong resemblance to some recent genus or species. Analysis (Gr. unloosing), in physics,

the separation of a compound body into its several parts.-In botany, it is synonymous with dissection in zoology.-In geometry, it is the method of establishing the truth of a proposition by certain analytical pro

cesses.

Anamorpho'sis, or Anamorphosis (Gr. change of figure), the distorted representation of an object.-In botany, the degenerated appearance of a plant through excess of development. Anamp'sis, a genus of acanthopterygious fishes, with fusiform bodies. -Cuvier.

Ananchi'tes (Gr. a gem), in palæontology, a genus of helmet-shaped fossil Echinidæ.

Anapai'ma, a tree of majestic size, which abounds in the rocky districts of British Guiana; and in commerce is appreciated for its fine, closegrained wood.

Anaplero'sis (Gr. to fill up), in surgery, restoration of parts destroyed, as in the healing of a wound. Anar'richas (Gr.), the Linnæan name of a genus of acanthopterygious fishes, allied to the Blennies.-The A. lupus is the sea-cat or wolf-fish of the British seas, which attains the length of six or seven feet, and is extremely voracious.

An'as (Lat. a duck), a genus of webfooted birds, of the family Anatida (which see).

Anasar'ca (Gr. ana, and sarx flesh), in pathology, a dropsical disease.-Anasarcous, relating to the dropsy. Anastal'tic (Gr. ana, and staltikos contracting), in medicine, styptic; astringent.

Anas'tasis (Gr. a raising up), in patho. logy, recovery from sickness; the transference of humours to other parts of the body.

Anastat'ic (Gr. reproducing), in the arts, a term applied to a new scientific process, by which designs produced either by the ordinary mode of printing from types, copper, or stecì plates, wood, stone, &c., or by manual operations of writing or drawing in prepared ink or chalk, may be readily transferred to the metal plate, and an indefinite number of copies produced at a really trifling cost.-National Cycl. Suppl.

Anastat'icon (Gr. resurrection), a cruciferous plant, known as the rose of Jericho, which, however dry it may be, has the property of recovering its original form, when immersed in water; order Cruciferæ.

Anas'toma (Gr. ana, and stoma a

mouth), a genus of terrestrial Testacea, belonging to the land Volutes.

Anastomatic (Gr.), in pathology, a medicine intended to remove obstructions. by opening the mouths of vessels, and promoting circulation. Anastomo'sis (Gr.), in physiology, the joining together the organs of circulation, as of the veins and arteries; the opening of the mouths of vessels of organized bodies to discharge their fluids into other vessels.-In botany, the union of the veins of leaves.-In entomology, the union of the nervures of the wings of insects.-Anastomosing is applied in anatomy, when blood-vessels open the one into the other; and in botany, when two parts, growing in different directions, unite and grow together.

Anas'tomus (Gr.), a genus of fishes with compressed heads and vertical mouths.

Anas'trous (Gr. without stars), in astronomy, a name applied to the twelve portions of the ecliptic, formerly possessed by the signs, but which, owing to the precession of the equinoxes, have since been deserted.

An'atase (Gr. extension), in mineralogy, the octahedral oxide of titanium; octahedrite. (See Titanium.)

Anat'ida (Lat. duck family), a family of birds of the order Natatores or Swimmers, including the Anserinæ, or geese and swans; the Anatina, or river ducks; the Fuligulina, or seaducks; the Phoenicoptine, or flamingoes, and the Merganida, or Mergansers, all of which have the bill very broad and the feet webbed. Anat'ifer (Lat.), a genus of Cirripeds (Barnacles), furnished with multivalve shells, by which they are enabled to adhere to rocks, or ships' bottoms.

Anatomy (Gr. cutting up), the art of dissecting animal bodies; the science which treats of the internal structure

of the human body.-Comparative Anatomy is the science which teaches the differences in the structure and organization of the animal kingdom. -Vegetable Anatomy teaches the structure of plants.

An'bury, a kind of gall produced by insects on the roots of cabbages, turnips, hollyhocks, &c.

Anceps, (Lat.), in botany, two-edged. An'chovy (Sp. anchova), a small seafish, of the Clupea or Herring tribe, closely resembling the common sprat, and extensively used in the manufacture of sauce.-Anchovy pear is the succulent fruit of the Persea gratissima, which in commerce is highly esteemed as an edible butyraceous production of the tropics. Anchu'sa (Gr. paint), a genus of plants, the Bugloss, so called from one of the species, A. tinctoria, being used for staining the skin; order Boragineæ. Anchylo'sis (Gr. to bend), in pathology,

a stiffness of the joints, arising from inflammation of the membrane lining the joints.-Anchylotic, pertaining to anchylosis.

Ancillarin'eæ, in conchology, a subfamily of Volutes, of which the Ancillaria, a genus of spiral univalve testacea, is the type.

Ancip'ital (Lat. anceps double), in botany, double-edged, compressed so as to form two opposite angles or edges. Ancis'trum (Gr. a hook), a genus of herbaceous plants, of the order Sanguisorbeæ.

An'cones, in architecture, the name of certain ornaments which depend from the corona of Ionic doorways; a sort of shoulder pieces, or brackets, which bear up the mouldings under which they are placed; ornaments cut in the key-stone of arches, serving to support busts, &c.

An'cony, in metallurgy, a bloom wrought into the figure of a flat iron bar. Ancyloblepharon (Gr. construction of the eyelid), in pathology, a disease of

the eye, by which the eyelids are closed, and vision obstructed. Ancyl'odon (Gr. bent tooth), a genus of acanthopterygious fishes; of the

family Chaetodon, and sub-family Sciæna.

Andal'usite, a mineral of a flesh-red colour and vitreous lustre ; thus named from Andalusia, in Spain, where it was first found.

Andan'te (Ital.), in music, distinct and exact.-Andantino, in a gentle manner, and slower than andante.-Andante largo denotes that the movement must be slow, distinct, and accurate.

An'darac, red orpiment. Andrea'a, a genus of mosses, of a brown or black colour.

Andre'na, in entomology, a genus of bees, which have three-clefted tongues. Andrody'namis (Gr. male power), in botany, a name applied to those plants which have a full development of petals and stamens. Androgynous (Gr. male and female), in botany, an epithet applied to plants which grow male and female flowers on the same root; as also to flowers containing stamens and pistils within the same envelope.-In zoology, applied to animals which naturally, as in the snail, combine, in their own structure, the organs necessary for the reproduction of the species. An'droid (Gr. like a man), an automaton resembling a human being. Andromeda (Gr.), in astronomy, one of the constellations in the northern hemisphere.--In entomology, a species of butterfly. In botany, a genus of plants, of the order Ericeæ. Andropet'alous (Gr. a male petal), in botany, a term applied to double flowers, which are produced by the stamens being converted into petals. Androph'agi (Gr. man-eater), cannibals.

Androt'omy (Gr. dissecting of men),

dissection of human bodies of the male sex.

Anely'tra (Gr. without a sheath), in entomology, those insects which have two or four membraneous wings, naked or hairy.

Anemog'raphy (Gr.), description of the winds.

Anemol'ogy (Gr. treatise on wind), the

science which treats on the cause, nature, and velocity of the wind. Anemom'eter (Gr. wind measurer), an instrument for determining the velocity and force of the wind.-Anemometrograph is an instrument for indicating on paper the force of the wind. Anem'one (Gr. the wind), a beautiful flowering plant, the Pulsatilla, or

wind flower, of the order Ranunculaceæ.-Anemonin is an inflammable cystallizable substance of the nature of camphor, obtained from the anemone.

Anem'oscope (Gr. view of the wind), an instrument for indicating the direction which the wind blows. Anen'tera (Gr. without intestines), in entomology, a class of polygastric infusoria, which have several stomachs but no intestinal duct. An'eroid (Gr.), applied to a peculiar kind of barometer, which consists of a small box, from which air is exhausted.

An'eurism (Gr.dilatation), in pathology, the diseased state of an artery, or other vessel, in which it is widened at any part, so as to form a bag or pouch. There are different kinds of aneurism: A. cordis, as the dilatation of the heart; A. verum, the uniform dilatation of all the coats of an artery; A. spurium, the dilatation of an artery in one direction, through disease of its coats; A. varicosum, a disease arising from a lancet passing through a vein, and wounding the subjacent artery.

Anfrac'tuous (Lat. winding), in botany, applied to the lobes of an anther, which are folded back on themselves, and doubled and bent, as in the cucumber.

Angel'ica (Lat.), a garden herb used in medicine and confectionery; an umbelliferous plant; so called from its agreeable smell and medicinal qualities. A. archangelica is a wellknown garden herb, sometimes candied with sugar, or eaten as celery. Angeli'na, the name of one of the recently-discovered planets, first observed by Tempel, in 1861. Angel-shot, chain-shot, being two halves of a cannon-ball. fastened to the ends of a chain.

Angel-water, a perfume consisting of rose, orange-flower, and myrtlewater, scented with musk and ambergris.

Angi'na Pec'toris (Lat.), a tightening or contraction of the thorax. Angiocar'pous (Gr. fruit vessel), in botany, an epithet applied to seed vessels which are enclosed within a covering that does not form a part of the fruit itself, as the filbert, acorn,

&c.

sperma seed), in botany, applied to plants the seeds of which are enveloped in a pericarp. Angiospo'rous (Gr.), in botany, applied to fungi which have their spore enclosed in cells.

Angios'tomous (Gr.), in conchology, applied to shells which have a straight opening nearly the length of the shell.

Angiot'omy (Gr.), the science or art of dissecting the vessels of the body. -Angiotomist is one who is skilled in angiotomy.

An'gle (Lat. a corner), the inclination of two lines to each other, which meet together at a point called the vertex. In geometry, a right angle is an angle formed by one straight line falling perpendicularly upon another straight line, and containing 90 degrees, or one-fourth of the circle. -Acute angle, an angle containing less than 90 degrees.-Rectilinear angle, an angle contained between two straight lines.-Curvilinear angle, an angle formed by two curved lines.-Obtuse angle, an angle greater than a right angle, or containing more than 90 degrees.— Oblique angles are either acute or obtuse, in opposition to right angles. -Spherical angles are formed by the meeting of two arches of great circles, which mutually cut each other at the surface of the sphere.-In optics, the angle of polarization, or angle of incidence, is the angle which a ray of light, refracted, makes with a perpendicular to the surface on which it falls;-Angle of reflection is always equal to the angle of incidence ;Angle of refraction is the angle which a ray of light makes with the surface of the refracting medium;Visual angle is the angle which is formed by two straight lines passing from the eye to the extreme points of any object.-In zoology, the facial angle is the angle made by the intersection of two lines, the one drawn from the farthest projection of the frontal bone over the anterior margin of the upper jaw; the other from the external opening of the ear along the floor of the nasal cavity.-In mechanics, the angle of draught is the angle made by the line of direction with a line upon the plane, over which the body is drawn, and perpendicular to that line of direction.-In Military Architecture and Fortification, the term Angle is of very extensive application: -Angles are formed by the several lines used in fortifying a place, or making it defensible, and are either real or