Acacia, a large group of trees with astringent and gum-yielding properties, natives of tropical Africa and Australia.
Academy, a public shady park or place of groves near Athens, where Plato taught his philosophy and whence his school derived its name, of which there are three branches, the Old, the Middle, and the New, represented respectively by Plato himself, Arcesilaos, and Carneades. The French Academy, of forty members, was founded by Richelieu in 1635, and is charged with the interests of the French language and literature, and in particular with the duty of compiling an authoritative dictionary of the French language. Besides these, there are in France other four with a like limited membership in the interest of other departments of science and art, all now associated in the Institute of France, which consists in all of 229 members. There are similar institutions in other states of Europe, all of greater or less note.
Acadia, the French name for Nova Scotia and New Brunswick.
Acanthus, a leaf-like ornament on the capitals of the columns of certain orders of architecture.
Acapul`co, a Mexican port in the Pacific, harbour commodious, but climate unhealthy.
Acarna`nia, a province of Greece N. of Gulf of Corinth; its pop. once addicted to piracy.
Acca`dians, a dark, thick-lipped, short-statured Mongol race in Central Asia, displaced by the Babylonians and Assyrians, who were Semitic.
Acca-Laurentia, the wife of Faustulus, shepherd of Numitor, who saved the lives of Romulus and Remus.
Acciaioli, a Florentine family of 15th century, illustrious in scholarship and war.
Accolade, a gentle blow with a sword on the shoulder in conferring knighthood.
Accol`ti, a Tuscan family, of 15th century, famous for their learning.
Accor`so, the name of a Florentine family, of 12th and 13th centuries, great in jurisprudence.
Accra (16), capital and chief port in British Gold Coast colony.
Accrington (39), a manufacturing town 22 m. N. of Manchester.
Accum, Friedrich, a German chemist, the first promoter of gas-lighting (1769-1838).
Accumulator, a hydraulic press for storing up water at a high pressure; also a device for storing up electric energy.
Acerra (14), an ancient city 9 m. NE. of Naples; is in an unhealthy district.
Acetic acid, the pure acid of vinegar; the salts are called acetates.
Acetone, a highly inflammable liquid obtained generally by the dry distillation of acetates.
Acet`ylene, a malodorous gaseous substance from the incomplete combustion of hydro-carbons.
Achæan League, a confederation of 12 towns in the Peloponnesus, formed especially against the influence of the Macedonians.
Achæ`ans, the common name of the Greeks in the heroic or Homeric period.
Achai`a, the N. district of the Peloponnesus, eventually the whole of it.
Achard, a Prussian chemist, one of the first to manufacture sugar from beetroot (1753-1821).
Achard`, Louis Amédée, a prolific French novelist (1814-1876).
Acha`tes, the attendant of Æneas in his wandering after the fall of Troy, remarkable for, and a perennial type of, fidelity.
Achelo`üs, a river in Greece, which rises in Mt. Pindus, and falls into the Ionian Sea; also the god of the river, the oldest of the sons of Oceanus, and the father of the Sirens.
Achen, an eminent German painter (1556-1621).
Achenwall, a German economist, the founder of statistic science (1719-1772).
Ach`eron, a river in the underworld; the name of several rivers in Greece more or less suggestive of it.
Ach`ery, a learned French Benedictine of St. Maur (1609-1685).
Ach`ill, a rocky, boggy island, sparsely inhabited, off W. coast of Ireland, co. Mayo, with a bold headland 2222 ft. high.
Achille`id, an unfinished poem of Statius.
Achil`les, the son of Peleus and Thetis, king of the Myrmidons, the most famous of the Greek heroes in the Trojan war, and whose wrath with the consequences of it forms the subject of the Iliad of Homer. He was invulnerable except in the heel, at the point where his mother held him as she dipt his body in the Styx to render him invulnerable.
Achilles of Germany, Albert, third elector of Brandenburg, "fiery, tough old gentleman, of formidable talent for fighting in his day; a very blazing, far-seen character," says Carlyle (1414-1486).
Achilles tendon, the great tendon of the heel, where Achilles was vulnerable.
Achmed Pasha, a French adventurer, served in French army, condemned to death, fled, and served Austria; condemned to death a second time, pardoned, served under the sultan, was banished to the shores of the Black Sea (1675-1747).
Ach`met I., sultan of Turkey from 1603 to 1617; A. II., from 1691 to 1695; A. III., from 1703 to 1730, who gave asylum to Charles XII. of Sweden after his defeat by the Czar at Pultowa.
Achit`ophel, name given by Dryden to the Earl of Shaftesbury of his time.
Achromatism, transmission of light, undecomposed and free from colour, by means of a combination of dissimilar lenses of crown and flint glass, or by a single glass carefully prepared.
Acierage, coating a copper-plate with steel by voltaic electricity.
A`ci-Rea`lë (38), a seaport town in Sicily, at the foot of Mount Etna, in NE. of Catania, with mineral waters.
A`cis, a Sicilian shepherd enamoured of Galatea, whom the Cyclops Polyphemus, out of jealousy, overwhelmed under a rock, from under which his blood has since flowed as a river.
Ack`ermann, R., an enterprising publisher of illustrated works in the Strand, a native of Saxony (1764-1834).
Acland, Sir Henry, regius professor of medicine in Oxford, accompanied the Prince of Wales to America in 1860, the author of several works on medicine and educational subjects, one of Ruskin's old and tried friends (1815).
Aclinic Line, the magnetic equator, along which the needle always remains horizontal.
Acne, a skin disease showing hard reddish pimples; Acne rosacea, a congestion of the skin of the nose and parts adjoining.
Acoemetæ, an order of monks in the 5th century who by turns kept up a divine service day and night.
Aconca`gua, the highest peak of the Andes, about 100 m. NE. of Valparaiso, 22,867 ft. high; recently ascended by a Swiss and a Scotchman, attendants of Fitzgerald's party.
Aconite, monk's-hood, a poisonous plant of the ranunculus order with a tapering root.
Aconitine, a most virulent poison from aconite, and owing to the very small quantity sufficient to cause death, is very difficult of detection when employed in taking away life.
Acorn-shells, a crustacean attached to rocks on the sea-shore, described by Huxley as "fixed by its head," and "kicking its food into its mouth with its legs."
Acoustics, the science of sound as it affects the ear, specially of the laws to be observed in the construction of halls so that people may distinctly hear in them.
Acrasia, an impersonation in Spenser's "Faërie Queen," of intemperance in the guise of a beautiful sorceress.
Acre, St. Jean d' (7), a strong place and seaport in Syria, at the foot of Mount Carmel, taken, at an enormous sacrifice of life, by Philip Augustus and Richard Coeur de Lion in 1191, held out against Bonaparte in 1799; its ancient name Ptolemaïs.
Acres, Bob, a coward in the "Rivals" whose "courage always oozed out at his finger ends."
Acroamatics, esoteric lectures, i. e. lectures to the initiated.
Acrolein, a light volatile limpid liquid obtained by the destructive distillation of fats.
Acroliths, statues of which only the extremities are of stone.
Acrop`olis, a fortified citadel commanding a city, and generally the nucleus of it, specially the rocky eminence dominating Athens.
Acrote`ria, pedestals placed at the middle and the extremities of a pediment to support a statue or other ornament, or the statue or ornament itself.
Acta diurna, a kind of gazette recording in a summary way daily events, established at Rome in 131 B.C., and rendered official by Cæsar in 50 B.C.
Acta Sanctorum, the lives of the saints in 62 vols. folio, begun in the 17th century by the Jesuits, and carried on by the Bollandists.
Actæon, a hunter changed into a stag for surprising Diana when bathing, and afterwards devoured by his own dogs.
Actinic rays, "non-luminous rays of higher frequency than the luminous rays."
Actinism, the chemical action of sunlight.
Actinomycosis, a disease of a fungous nature on the mouth and lower jaw of cows.
Actium, a town and promontory at the entrance of the Ambracian Gulf (Arta), in Greece, where Augustus gained his naval victory over Antony and Cleopatra, Sept. 2, 31 B.C.
Acton, an adventurer of English birth, who became prime minister of Naples, but was driven from the helm of affairs on account of his inveterate antipathy to the French (1737-1808).
Acton, Lord, a descendant of the former, who became a leader of the Liberal Catholics in England, M.P. for Carlow, and made a peer in 1869; a man of wide learning, and the projector of a universal history by experts in different departments of the field; b. 1834.
Acts of the Apostles, a narrative account in the New Testament of the founding of the Christian Church chiefly through the ministry of Peter and Paul, written by Luke, commencing with the year 33, and concluding with the imprisonment of Paul in Rome in 62.
Acun`ha, Tristram d', a Portuguese navigator, companion of Albuquerque; Nuna d', his son, viceroy of the Indies from 1528 to 1539; Rodrique d', archbishop of Lisbon, who in 1640 freed Portugal from the Spanish domination, and established the house of Braganza on the throne.
Acupressure, checking hemorrhage in arteries during an operation by compressing their orifices with a needle.
Acupuncture, the operation of pricking an affected part with a needle, and leaving it for a short time in it, sometimes for as long as an hour.