Page images
PDF
EPUB

ACCIPITRIDE-ACENAPHTHENE

signature, i.e., in the course of a composition, and altering the pitch of the notes before which they are placed. They are the sharp (), which raises such a note a semi-tone; the doublesharp (x), which raises the note a whole tone; the flat (b), which depresses the note a semi-tone; the double-flat (bb), which depresses the note a whole tone; and the natural (). which cancels the changes effected by the other symbols. There is no uniformity in the use of accidentals in reference to the duration of their validity, though generally their effect is limited to the measures in which they occur.

Accipitridæ (Falconidae). Family of raptatorial birds, having feathered heads, and eyes more or less sunken and furnished with eyebrows. Metatarsus is sometimes feathered. Here belong Aquila, the eagle: Milvus, the kite; Buteo, the

A. nisus, Eur. Sparrow-Hawk. buzzard; Astur, the goshawk, the falcons and harriers. The bald eagle (Haliaëtus leucocephalus) has the head, neck and tail white after the third year. It lives on fish robbed from the Osprey.

Accius, or Attius, LUCIUS, ab. 170-86 B.C. Latin tragic poet, praised for vigor and sublimity of thought. He also wrote Annals in verse, and several prose works. Acclimatization. Process of adaptation an organism undergoes to fit it for new conditions of life.

Accolade. Act of salutation which accompanied the bestowing of knighthood; originally an embrace or kiss, later a light blow with the flat of a sword. In French Gothic architecture, the meeting and curving upward at the center of the moldings decorating the edge of a lintel or a flat arch.

Accommodation. Term used in psychology, physiology and opthalmology, to denote the alteration in the eye which is necessary in order that one may see distinctly when one looks from distant to near objects, or the reverse. tinct vision there must be a sharp image on the retina, and For disfor the normal eye at rest only rays from distant objects are brought to a focus there. When we look at objects near by the rays are brought to a focus by an increase in the curvature of the lens, which is felt to involve an effort. Some eyes cannot accommodate for distant objects, being myopic or short-sighted. Others cannot for near objects, being hypermetropic or far-sighted.-In theology, the exceptionable doctrine that Christian teachers, for essential ends, may speak as if accepting incidental beliefs which they do not hold.

Accommodation Note. Indorsed by one or more parties, given and discounted for money advanced and not for payment of debt.

Accommodation of the Eye. Function or property of the eye by which near and distant objects can be seen clearly. This is accomplished by the contraction or relaxation of a circular muscle (celiary muscle), which lies behind the crystalline lens, thus increasing or decreasing its convexity and accommodating it to near or remote vision. The natural changes which occur as the age increases render the lens less elastic, and its convexity cannot be increased sufficiently to

allow of near vision.

Accompaniment, IN MUSIC. Speaking generally, all the elements in a composition are subsidiary to the principal part. In primitive music the accompaniment is chiefly rhythmical, hand-clapping or drumming; with the development of the

melodic capacity of instruments it becomes melodic and, later, melody. In the European music of to-day, the accompaniment harmonic. In a sense all harmony is an accompaniment to is generally a subsidiary instrumental part, added either to support the principal voice or voices, or to lend fullness, richness or color to a composition. Additional accompaniments musicians to pieces composed at a time when it was customary are the parts, generally orchestral, contributed by modern to leave to the accompanist at the organ or harpsichord the task of filling in harmonic parts contemplated and suggested by the composer but not written down; also to compositions, the original effect of which can no longer be reproduced because of the disuse of certain instruments.

Accomplice. One who is associated with others in the commission of a crime, whether as principal or accessory. A special signification of the term is one who gives evidence against his associates.

Accord and Satisfaction. Agreement whereby the claim of A against B is discharged, upon A's acquisition of a new right against B, or of new rights against B and others, in place of the original claim. If A accepts B's offer to perform something new in satisfaction of an old claim, there is an accord, but there is no satisfaction until full performance is made.

Accordion. Musical instrument, invented in Vienna 1829; a mechanical extension of the principle underlying the mouthorgan. The tones are produced by metallic reeds vibrating freely in a slot and governed by keys placed on one side of a pair of bellows operated by both hands of the performer.

Account. Statement of a fiduciary's receipts and expenses, or of the mutual dealings of merchants. If running or unsettled, it is called an account current; if adjusted and a balance struck, either by express or implied agreement, it is an account stated. The liability to account is sometimes enforced by a common law action, but generally by a suit in equity.

Accretion. Title acquired by the owner of land to the gradual accumulation of soil along a river-bank or seashore. Accumulation of Wealth. Saving of utilities produced by human effort, distinguished from their consumption or waste by neglect. To this is due all wealth, whether in capacities. the improvements of property, money, or human industrial

cal energy in the form of potential energy of chemical sepaAccumulator, ELECTRIC. Apparatus for storing electriration. Plante's consisted essentially of two lead plates immersed in dilute sulphuric acid, the surface of one of these plates being converted into peroxide and that of the other into spongy lead by the action of the current. Faure and lead oxide. At present the plates are cast with perforations Brush modified this by covering both plates with a layer of passed through a cell made of such plates the lead oxide on into which the active material is pressed. If a current be the negative electrode is converted into spongy lead, while

[graphic]
[ocr errors][merged small][merged small]

that on the positive electrode is oxidized to lead peroxide. action takes place and the stored energy again appears in When the two electrodes are joined by a conductor a reverse the form of an inverse electric current. A number of such cells joined together is called a "storage" or "secondary battery." The Plante type, modified by greatly increasing the surface of the plate to be corroded, seems to give the best jar is sometimes called an accumulator. results in practice. An electric condenser such as a Leyden

Accumulator, HYDRAULIC. Cylinder fitted with a piston upon which is a weight. Water is pumped into the cylinder under very great pressure, and the apparatus thus becomes the source of a large amount of potential energy, which may be distributed by pipes for the various operations of hydraulic engineering.

Aceldama (FIELD OF BLOOD"). Near Jerusalem; so called as having been bought with the blood-money paid to

Judas.

95°C. White crystalline solid hydrocarbon found in coal-tar. Acenaphthene, or ETHYLENE-NAPHTHALENE. C,,H,,.Mpt.

ACEPHALA-ACETYLENE

It is a combination of ethylene and naphthalene, and is formed by heating them together.

Acephala. Group including those dendrocolous worms whose anterior end is not specialized into a distinct head. Polycladus is an example. The term is also applied to the Lamellibranchs.

Acephali (HEADLESS). Epithet applied to bishops or heretics who were under no proper ecclesiastical jurisdiction, or who, as the Eutychians in 452, revolted from it.

Acephalocyst. Sterile cyst of an Echinococcus or Cysticercus (q.v.).

Acer campestre. Maple tree of family Aceraceae, valua

11

Acetate of Chromium. Cr, (C,H,O,). Found in trade in the form of a green liquor and prepared from chromium hydroxide and acetic acid, or from chrome alum and acetate of lime. Used in textile coloring.

Acetate of Copper. Cu(C,H,O,), Dark green crystals containing water; combining readily with arsenic salts of copper to form brilliant greens, as Paris green. See VERDIGRIS. Acetate of Iron. Fe(C,H,O,). The aqueous solution of this salt is known in commerce as iron liquor," also "black liquor." It is prepared by the action of acetic acid on scrap iron; or, more commonly, from copperas and acetate of lime. Used in dyeing and calico printing.

66

Acetate of Lead. Pb(C,H,O,). Known also as "sugar of lead." White crystals, containing water of crystallization; made by the action of acetic acid upon lead; it is the most important soluble lead salt.

Acetic Acid. CH,COOH. Bpt. 119° C. The acid of vinegar, and made from alcohol by oxidation; also obtained, together with methyl alcohol and tar, by the dry distillation of wood in iron stills connected with copper condensing worms. The acid is neutralized with lime, forming gray acetate of lime, which is decomposed in bronze stills with sulphuric acid,

[graphic][merged small]

ble for timber, shade and ornament. Sap of Acer saccharum or sugar maple is source of maple sugar.

Aceraceæ. Natural family of trees and shrubs, including all the maples. Commonly known as the Maple Family. Acerra. In Roman Antiquities, a small box used to hold incense, borne in processions; also a small altar for burning incense beside a dead person before the last rites.

Acestes. Sicilian, son of a river-god and a Trojan, whose arrow was shot with such force as to take fire amid the clouds. Eneid, V., 525.

Acetabulum. (1) One of the lobes of the placenta of ruminants. (2) One of the sucking cups of the cuttle-fish. (3) The depression in the epimerum of an insect's segment which receives the coxa of the leg. (4) In anatomy it is the socket of a ball and socket joint, as at the hip.

Acetacetic Ether. CH,.CO.CH,.COOC,H,. Ethyl acetacetate. This salt of acetacetic acid (CH,.CO.CH,.COOH) is obtained in the form of a sodium compound by the action of sodium upon ethyl acetate. Liquid, much used in syntheses in organic chemistry.

The

Acetal. CH, CH(OC,H,). Bpt. 104° C. Liquid formed by heating ordinary aldehyde with common alcohol. term "acetals" is sometimes applied to the class of compounds formed by heating aldehydes and alcohols. These compounds are in reality ethers.

Acetaldehyde. CH,.CHO. Bpt. 21° C. Called also aldehyde and ethyl aldehyde. Liquid formed by the gentle oxidation of ordinary alcohol. It has a characteristic pungent odor and is easily changed to its polymer, para-aldehyde. Found in the first runnings from the alcohol still.

Acetates. Salts of acetic acid.

Acetamide. C,H,O.NH,. An ammonia in which one atom of hydrogen has been replaced by an acetyl group. Made by heating ammonium acetate. A white crystalline solid, very weakly basic in character.

Acetanilide, or PHENYLACETAMIDE. C,H,.NH.C,H,O, generally known by the copyrighted name of Antifebrin; produced when aniline and acetic acid are heated together. It is a white, shining, micaceous crystalline powder, used in medicine as an antipyretic in fevers; also in rheumatism, neuralgia and headaches. Dose, 2 to 10 grains. In some cases it has produced faintness, palpitation and cyanosis. Discovered by Gerhardt, 1853, applied by Kussmaul, 1886.

Stills for Distilling Wood.

the acetic acid being set free and condensed in a copper worm. 1000 parts of oak wood yield 20 parts of acetic acid. It is largely used in the arts, in the manufacture of white lead, and, in combination with bases, forms acetates; it is also used in medicine.

Acetic Anhydride. CH,.CO.O.OC.CH,. Bpt. 137° C. A liquid of acid character, equivalent to two molecules of acetic acid less one molecule of water. Forms acetic acid with water. Made by the action of acetyl chloride upon sodium acetate. Used extensively in organic chemistry as à reagent.

Acetic Ether. CH,.COOC,H,. Bpt. 75° C. ETHYL ACETATE. Liquid of pleasant odor, produced from ordinary alcohol and acetic acid by means of a water absorbent. Used as a solvent and in the preparation of perfumes and flavors.

Acetines. Compounds produced by the action of glycerine upon acetic acid. Heavy liquids used as solvents for colors in calico printing. See TRI-ACETINE.

Acetoluide. CH,.C,H,.NH.C,H,O. Known in three forms: para-, meta- and ortho-acetoluide of different molecular forms. The compounds are prepared by heating the toluidines with acetic acid or acetic anhydride.

Acetone. CH,.CO.CH,. Bpt. 56° C. Dimethyl ketone. Liquid of ethereal odor, present among the products of the dry distillation of wood, but produced usually by heating dry acetate of lime. Used as a solvent and in the nianufacture of chloroform.

Aceto-Nitrile. CH,.CN. Methyl cyanide. The nitrile corresponding to acetic acid. Prepared by the action of methyl iodide upon cyanide of potash. Liquid with characteristic odor resembling oil of bitter almonds.

Aceto-Phenone. CH.CO.CH,. Phenyl-methyl ketone. Liquid of pleasant odor. Easily solidifies. Prepared by heating a mixture of benzoate and acetate of calcium.

Acetoxime. CH,C.NOH.CH,. White crystalline solid, produced by the action of nitrous acid upon acetone.

Acetyl. CH,.CO-. This group enters into combination with hydroxyl (OH) to form acetic acid, and into a vast number of organic compounds as a constituent.

Acetyl Chloride. CH,.COCI. Combination of the acetyl group with chlorine. Colorless, fuming liquid, changed by water into acetic acid and hydrochloric acid. Prepared by the action of the phosphorus chlorides upon acetates and acetic acid. Very much used for introducing acetyl into compounds.

Acetylene. CH: CH. Gaseous hydrocarbon formed by the imperfect combustion of illuminating gas. It has an unpleasant, characteristic odor. Combines with chlorine and bromine. The hydrogen can be replaced with certain metals, as copper and silver. These compounds are very explosive.

12

ACETYLENE COPPER-ACID FUCHSINE

Acetylene Copper. Dark red powder formed by the union of acetylene with cuprous salts. Very explosive when heated or struck.

Acetylene Series. Series of hydrocarbons in which a triple bonding between carbon atoms is conceived to exist. For example, acetylene HC:CH; allylene CH2-C÷CH.

Achæan League. Coalition at first of four, soon of nearly all the towns in Achaia, ab. 280 B.C., afterward increased by Sicyon, Corinth and others; in 191 B.C. it included Athens and Sparta. It maintained Greek independence against Rome for 50 years preceding the fall of Corinth, 146 B.C.

Achæmenidæ. Family of Persian kings, ruling ab. 730

430 B.C.

Achæta (SIPUNCULOIDEA or INERMES). Gephyrean worms with terminal mouth, dorsal anus, no setæ, and with the anterior region of the body retractile. There is no proboscis, but sometimes (Sipunculus) a circle of tentacles about the mouth, and all traces of metamerism is lost. The Priapulidæ have no tentacles and the intestine is straight (coiled in Sipunculida), and there are pharyngeal teeth.

Achaia. District of Peloponnesus, n. of Arcadia and Elis; after 146 B.C. the name of the Roman province including all Greece s. of Thessaly and e. of Ætolia.

Acharius, ERIK, 1757-1819. Swedish lichenologist. Methodus qua omnes delectos Lichenes, 1803; Lichenographia universalis, 1810; Synopsis methodica Lichenum, 1814.

Achates. Friend and companion of ENEAS (q.v.). His loyalty to his chief has made fidus Achates a synonym for a devoted follower.

Achenbach, ANDREAS, b. 1815. pupil of the Düsseldorf Academy. Achenbach, OSWALD, b. 1827. brother and pupil of ANDREAS.

German landscape painter;

German landscape painter;

[blocks in formation]

Acherusia. Lake in Epirus into which the Acheron flows; also, a cavern in Bithynia, regarded as an entrance to the lower world. Through it Hercules is said to have dragged Cerberus up to the daylight.

Achilles. Chief hero of the Iliad; son of Peleus, king of the Myrmidons, and the Nereid Thetis, who sought to make him immortal by dipping him in the Styx, all but his heel. When nine years old, disguised as a maiden, but detected by Ulysses, he joined the Greek army. He sulked and refused to fight, because Agamemnon took Briseis from him; avenged the death of his friend Patroclus by slaying Hector and dragging his body behind his car; slain at the Scaan gate of Troy.

Achilles Tatius. Rhetorician of 5th century. He wrote the romance of Cleitophon and Leucippe, one of the best of Greek love stories.

Achlorophylleæ. Division of the Protophyta, including all the forms in which chlorophyll is wanting and comprising yeast and bacteria.

Achmed III. Sultan of Turkish empire, 1703–30. In a war with Russia, Peter the Great was forced to surrender at Hush, 1711. Morea was recovered 1715, Belgrade lost 1719. Achmed Pasha. See DJEZZAR.

Achocon. In Peru, a large tree of the Violet Family, Leonia glycycarpa, producing a large pulpy edible fruit.

Achromatic Object Glass. One which brings all the rays of light to a common focus. It consists of a combination of two or more lenses made of different kinds of glass, the curves being so adjusted that the dispersion caused by one shall be corrected by the other or others.

Achromatin. Substance occurring in the nucleolus of vegetable cells, which does not stain when treated with ordinary coloring reagents. It constitutes the nuclear sap and the spindle or the reticulum, which is supposed to be metamorphosed into the spindle during cell division.

tions might be constructed which would give achromatic (colorless) images. The principle is now applied to nearly all optical instruments.

Achromatopsy. Affection of the eye which renders us incapable of correctly distinguishing colors. It is commonly known as color-blindness. The commonest form is that of red

blindness, in which case red appears black or bluish green. Dalton was peculiarly afflicted in this regard, and from the fact that he carefully described it the disease is often called "Daltonism."

Achroot. East Indian dye plant, Morinda tinctoria, of the natural family Rubiacea.

Acid. Substance containing hydrogen which may be replaced, either wholly or in part, by a metal, when the acid is brought in contact with either a metal, a metallic oxide, or a metallic hydroxide. Acids usually possess a corrosive action, a sour taste, and the power to change certain vegetable colors from blue to red. When treated with a base (q.v.) acids form a salt and water.

Acids are divided into two classes: those containing oxygen are called oxy-acids; those containing no oxygen are called bydracids. They are further divided according to the number of replaceable hydrogen atoms which they contain. An acid having one replaceable hydrogen atom is a monobasic acid; atoms of replaceable hydrogen; as H,SO,. Similarly there are for example, HCI. Dibasic acids are those containing two tribasic, tetrabasic, pentabasic acids, etc.

If the proportion of oxygen varies, then that one containing the larger proportion of oxygen is given a name ending in ic; to the one having the smaller proportion of oxygen, a name ending in ous. If there is a third, with a still smaller with the descriptive term. proportion of oxygen, the prefix hypo is used in connection Thus the compound H,SO, is called sulphuric acid; H,SO,, sulphurous acid; H2SO,, hyposulphurous acid. An acid containing the same elements, but a larger proportion of oxygen than H,SO,, is designated persulphuric. In designating hydracids the names of the eleeither hydrochloric or chlorhydric acid. ments in the compound are generally used: thus HCl is

An organic acid is a combination of one or more carboxyl (COOH) groups, or one or more acid groupings derived from a mineral acid with any organic grouping, but this union is directly with a carbon atom. Examples: acetic acid, CH,. COOH., benzene-sulphonic acid, CH ̧.SÓ,.OH.

Both mineral and vegetable acids enter largely into human food, usually in combination as salts.

From a medical standpoint these bodies are divided into the elements from which they are derived, as, for example, three classes: one including those whose action depend upon phosphoric acid; another embracing those, such as carbolic third which takes in those used principally as neutralizers of acid, which have properties peculiar to themselves; and a alkalies and as corrosives, and is the class most commonly termed acids. It includes the mineral acids, nitric, muriatic and sulphuric; and the organic acids, acetic, citric and tartaric.

too

destroy unhealthy and morbid growths, while the organic are The mineral acids are highly corrosive and are used to but feebly so, with the exception of acetic. Both classes when freely diluted relieve thirst, and when taken before eating. increase the acidity of the stomach, but have the opposite effect when taken after meals. When administered in large quantities and for too long a time, they give rise to a condition resembling scurvy. They have been used to a considerable extent to purify water containing disease germs, especially those of Asiatic cholera, and with considerable success. The salts of the organic acids are as a rule soluble, alkaline and increase the amount of the urine. and when of the alkaline bases render all the fluids of the body

Acidic. When applied to the crystalline rocks, having a large percentage of silica, especially in a free state, as in most granites and gneises.

Acid Aromatic. Combination of carboxyl (-COOH) or the group HOSO, with a nucleus of carbon atoms combined with each other in a ring form, as in benzene. The acids of the aromatic or benzene hydrocarbons.

Acid Colors. Those capable of fixation upon wool in a bath acidified with sulphuric or acetic acid. As found in trade, they are mainly sodium salts of organic acids or phenols.

Achromatism. As all refracting media are also dispersing media, it is clear that images formed by lenses will in general be colored at the edges. Newton supposed that in all cases the amount of dispersion was proportional to that of refraction, and thus that refraction without dispersion was impossible. It was found, however, by Hall in 1733, and subsequently by Dollond, that such is not the case, but that by Acid Fuchsine. Mixture of the sodium salts of trisulusing two or more optically different media, lens combina-phonic acids, prepared by the action of sulphuric acid upon

They are monobasic, and those of low molecular weight are Acid, Fatty. Organic acids combined in the ordinary fats. liquids, while those of high molecular weight are solids.

ACID GREEN-ACREDULA CAUDATA

13

para-rosaniline and rosaniline. It dyes wool magenta in an acid bath; known also as acid magenta and fuchsine S.

Acid Green. C,,H,,N,O,,S,Na,. Sodium salt of diethyldibenzyl-diamido-triphenylcarbinol-trisulphonic acid. Green powder soluble in water; it dyes wool green in an acid bath. Acid Magenta. See ACID FUCHSINE.

Acid Tartrate of Potassium. See CREAM OF TARTAR. Acid Violet, 6 B. CH,O,SNa. Mainly sodium salt of penta-methyl-benzyl-para-rosaniline sulphonic acid, which is prepared from Methyl Violet 6 B by the action of sulphuric acid upon the base. Violet powder.

Acid Yellow S. C,,H,N,OS Na,. Sodium salt of the sulpho acid, prepared from dinitro-a-naphthol, by the action of sulphuric acid upon it. Orange yellow powder, easily soluble in water; it dyes wool yellow.-Acid Yellow. An impure sodium salt of amido-azo-benzene disulphonic acid. Yellow powder, soluble in water; called also Acid Yellow G. Acid Yellow R is the salt of the corresponding toluene compound.

Acidimetry. Process of determining the strength of a given solution of acid by means of a standard solution of an alkali.

Acidum Phosphoricum Glaciale. See PHOSPHORIC ACID, GLACIAL.

Acinetaria. Class of Infusoria including two orders, Suctoria and Non-Suctoria, according as whether sucking tentacles are present or not. The young are ciliated, while the adults are sessile, and even form stolons that branch, the nucleus passing continuously into all the branches. Sporefruit is formed at the ends or sides of the branches. Acineta is an example.

Acipenser. See CHONDROSTEI. Acknowledgment. Declaration before an authorized person, by one who has executed an instrument, that it is his deed; also the certificate of this fact. The persons authorized to take acknowledgments, and the forms to be observed, are generally regulated by statute.

Acorus Calamus (SWEET FLAG). Genus of aromatic plants, family Araceae.

[graphic]

Acosta, GABRIEL, or URIEL, 1594-1647. Apostate, of Jewish descent, but educated as a Christian. He went from Portugal to Holland, became a Jew, and for certain heresies was excommunicated by the rabbis.

Acoustics. That branch of physics which treats of the production, transmission and comparison of sounds. See SOUND.

Acrania. Division of
Vertebrata characterized
by the absence of a cra-
nium. A simple brain is
present. Amphioxus is
the only representative.
See LEPTOCARDII.

Acraniate. Said of
Chordate animals like
Amphioxus, which lacks a
cranium.

Acrasiaceæ. Family
of Myxomycetes or slime-
moulds.

Acorus Calamus.

Acraspeda, or ACRASPEDOTA. The coveredeyed" Medusæ include those jelly-fish whose eyes are sunk in special pits in the edge of the umbrella-shaped body. They form the group Scyphomedusa, also sometimes termed Discomedusce and Lucernarida.

Acre. Unit of superficial measure of land, 160 sq. rods, or 43,560 sq. ft. A square acre will measure a little less than 209 ft. on each side. The acre of the U. S. is the same as the statute

Aclidian, or ACLEIDAN. Having no clavicles; e.g., the or "English" acre of Great Britain. ungulates and dogs. Cats have rudimentary clavicles.

Aclinic Line. See INCLINATION.

Acmite. Silicate of sodium and iron, named from the pointed form of its crystals; first found in Norway. Acœla. Same as Acoelomata: includes Sponges and Coelenterata, these groups lacking a true body cavity distinct from the digestive canal.

Acolyte. Attendant; highest of the four minor orders of R. C. Ch.

Aconcagua. Peak of the Andes, in Chili, highest on the American continent, so far as known. Altitude 23,910 feet. Acone Eye of Insects. One composed of retinulæ of six visual cells, surrounding a central cell, each containing a rhabdomere. Aconite.

Plants of the genus Aconitum, especially A.

Monk's-hood (Aconitum napellus).

napellus and A. ferox, na-
tives of the old world. Known
also as Wolf's-bane and
Monk's-hood. There is scarce-
ly any drug which is so effect-
ive in lowering elevated tem-
peratures of the body as this;
but, on account of its de-

pressing action upon the

heart, considerable caution is
necessary in its use. Both
the tuberous root and leaves
are used in medicine in cases
of rheumatism, neuralgia,etc.
Aconitic Acid. C,H,.
(COOH),. Mpt. 186° C. A tri-
basic acid found in aconite,
sugar cane, beet root and oth-
er plants. It is a white crys-
talline solid, easily soluble

in water.

[blocks in formation]

Acre, or AKKA. Anciently Ptolemais; important city on coast of Syria, the "key of Palestine," taken by Saracens 638, by Crusaders 1110, retaken by Saladin 1187, recovered by Crusaders 1191, after two years' siege, with loss of 100,000 soldiers, and named St. Jean d'Acre; regained by Saracens 1291, when 60,000 Christians perished; fell into hands of Turks 1517. Bonaparte failed to take it by a two months' siege 1799. Mostly destroyed in siege of nearly six months by Ibrahim Pasha 1831-32; stormed and taken by English Nov. 3, 1840, and handed over to Turks 1841. Pop. ab. 8,000.

Acredula caudata. Genus Titmouse, family Paridæ, characterized by length of tail.

[graphic]
[graphic]

Acredula caudata.

14

ACRIDIIDE-ACTINOTROCHA

Acridiidæ (GRASSHOPPERS). Saltatorial Orthoptera. The posterior pair of legs are very strongly developed. The antennæ are short, the anterior wings are stiff and fold vertically over the membranous wings. The ears are on each side of the metathorax. The chirping sound of these insects is made by the male, by rubbing the femora of the jumping legs against the nervures of the wing covers. They are gregarious and feed on plants.

Acridine. C,,H,N. Aromatic base with intensely irritating action upon the mucous membrane. Present in the crude anthracene obtained from coal-tar. Combines with mineral acids.

Acrocarpi. Division of mosses characterized by bearing the sporophyte at the ends of the stem or branches.

Acrocephalus. Reed-warblers, sub-family Sylviince, char

acterized by relatively large bill. Found in northern hemisphere; also in India and Australia.

Acrodont. Group of fishes, chiefly Liassic, whose oblong pavement-like teeth contain one single rounded tubercle.

Acrodont Dentition. Teeth on margin of the jaw in Reptiles. Such teeth are not sunk in sockets in the jaw-bone, but stand on the top of its edge.

Acrogens. See PTERIDOPHYTA.

Acroleine. CH,: CH.CHO. Bpt. 58° C. Acrylic aldehyde; allyl aldehyde. An aldehyde produced by the oxidation of allyl alcohol and in the decomposition by heat of fats and glycerine. A liquid of pungent odor and violent action upon the eyes. The smell of burning fat is due to its presence.

Acrolith. Ancient form of Greek religious statuary, in which the main figure was made of wood, while the hands, arms and feet were of stone. These figures were clothed in garments which were plaited in zigzag folds, and the first entirely stone figures of Greek art show, if draped, an imitation of these zigzag lines. The art of the period which produced these figures was wholly rudimentary and unscientific, the form being no more than a puppet; but such figures of the gods were still venerated in the period of superior art, and the most sacred Athenian statue, an Athene kept in the Erechtheum, was of this class. The famous Panathenaic festival and procession was celebrated in order to give this figure a new garment at stated intervals. The period of the Acroliths must have lasted as late as the seventh century B. C., for stone sculpture of entire figures was certainly not largely practiced before this time. Although there are no remains of such figures, there is a Greek vase in Naples which furnishes a faithful picture of one in its shrine.

Acrophalli. Group of nematode worms in which the male reproductive organ is terminal. It includes Dochmius, Trichina, Trichocephalus, etc.

Acropolis. Citadel hill. Such fortresses were the natural centers of the earliest civilized settlements of Greece and Italy, and in Greece they are especially prominent. On the fortressed hill were built the first and therefore the most sacred shrines and temples of the future city. Here was, in still later days, after the city had grown up around the hill, the place of refuge and the last resort of desperate defense. Especially noted citadels were those of Argos, Mycenæ, Thebes, Corinth and Athens.

Acropolita, GEORGIUS, 1220-1282. Byzantine diplomatist and historical writer.

Acrostichaceæ. Order of Filices, including a great many tropical species.

Acroteria. In classic architecture, pedestals placed at the angles of the pediments of temples for the reception of statues or ornaments of any kind; also the ornaments themselves.

Acrylic Acid. CH2:CH.COOH. Monobasic, unsaturated acid, combines therefore readily with active chemical agents, forming dibrompropionic acid with bromine. White crystalline solid prepared from acroleine by oxidation.

Acrylic Aldehyde. See ACROLEINE.

Act of War. Act of violence or attack by a main army, equivalent to a declaration of war by the nation sanctioning it, to the rupture of a treaty, or the ending of an armistice. Acta Consistorii. Edicts of the council of state under the Roman emperors.

Acta Diurna. Species of official gazette issued daily in ancient Rome, which chronicled all important events and the proceedings of the Senate; this last was not usual before Julius Cæsar.

Acta Sanctorum, or ACTA MARTYRUM. By the Bollandist Jesuits: biographies of the saints of the Roman calendar, according to their days; continued for 250 years, still going on. Vol. I. appeared 1643, Vol. LXV. 1892.

Actæon. Huntsman who, because he once saw Artemis (Diana) bathing, was changed by her into a stag, and torn in pieces by his own dogs.

Actheres. See SIPHONOSTOMATA.

Actian Games. Celebrated at Actium, in honor of Apollo; revived by Augustus to commemorate his victory there.

Actinal Surface. Region which bears the mouth in Echinoderms. In star-fishes it is the flat side, that on which the animal crawls. Also called the ambulacral surface.

Actinaria. Group of Zoantharia, which includes the Actinia (sea anemone). It secretes no hard parts. See MALACO

[graphic]

DERMATA.

Actinic Rays.

See RADIATION.

Actinidæ. Family of Actinarian corals, including Actinia the sea anemone. This is a sack or cylinder-shaped organism composed of soft. often brightly colored, tissues. It is fastened by one end to some object and on the other bears a crown of tentacles that, when expanded, resemble the corolla of a flower. In the center is the mouth, with a short oesophagus leading into a space that communicates in all radii with the spaces between the mesenteries. The latter are vertical partitions that project from the body wall toward the center.

[merged small][merged small][merged small][merged small][graphic][merged small][merged small][merged small][merged small][merged small][merged small]
« PreviousContinue »