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.

ACOEMETAE, 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 “Faerie 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 Ptolemais.

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 Caesar 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.

ACTAEON, 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.