ceded Pond as royal astronomer of the Greenwich Observatory, where he introduced or perfected numerous astronomical instruments, devised clearer and quicker methods of calculation, and instituted valuable researches in magnetism, meteorology, and photography. One of his most important achievements was the establishment of a mechanical device in the form of magnets and iron, whereby the disturbance of the compass in iron-built vessels can be rectified. It was he, also, who conducted the astronomical observations preparatory to the definition of the boundary between Canada and the United States. Among the works written by this distinguished scientist during his exceptionally long and useful career, the following are especially noteworthy: Gravitation, for the Penny Cyclopædia, also published separately (1885); Mathematical Tracts on Physical Astronomy (fourth edition, 1858); Ipswich Lectures on Astronomy (fourth edition, 1858); Treatises on Errors of Observation (1861); Sound (1869); Magnetism (1870); "Trigonometry," "Figure of the Earth," "Tide and Waves," in Encyclopædia Metropolitana.
AÏSH-KUL, ii'esh-kool'. See Ala-Kul.
AISLE, il (Fr. aile, wing, from Lat. ala, contracted from axilla). An architectural term meaning the lateral section of the interior of any building which is divided by rows of piers or columns. In such interiors the higher and broader central section is called the nave; the narrower, lower sections are the aisles, divided from the nave or from each other by the lines of supports. There are a few cases of such an arrangement in Greek temples. The development of interiors of this type came with the rise of the Christian basilica or church in the fourth century, when the smaller churches had two and the larger ones four aisles on either side of the central nave. In contemporary circular or polygonal buildings — especially baptisteries, mausoleums, and chapels — the central dome was often encircled by one or more concentric lines of arcades, forming aisles with lower ceiling or vault. When, in the Middle Ages, the upper parts of the church — transept and choir — were so much enlarged under monastic influence and the development of cathedral architecture, then the aisles were continued around the transept and the apse, thus adding great richness to the interiors. In a few cases there were as many as three aisles on each side of the church. They varied very much in height, according to schools, periods, and methods of construction: and in some schools (Lombard, Norman, Byzantine, Early Gothic. etc.), they were surmounted by open galleries, and sometimes by closed galleries (south of France); while in other cases, especially in the early vaulted Romanesque, the vaults of the aisles reached almost as high as those of the nave.
There are several improper uses of the term: in the case of hall-churches with two, three, or more naves of equal height, these divisions are sometimes incorrectly called aisles. Also, in modern usage it is wrongly applied to the passageway between two rows of seats in a building. See Church.
AISNE, fin. A tributary of the Oise, which
rises in the department of Meuse, France. It
flows northwest through the departments of
Ardennes, Aisne, and part of Oise, where it falls
into the river Oise above Compiègne ( Map:
France, K 2). Its length is 170 miles, of which 34 are navigable. It is connected with the Meuse and Marne rivers by canals.
AISNE, an. A department in the north of
France (q.v.), formed of parts of the old Picardie, Bril, and Île-de-France. Capital, Laon.
AÏ'SSÉ, iiV-sA'. Mademoiselle (1694?-1733).
A French writer, born in Circassia. She was
taken captive by a Turkish marauding expedi-
tion, and about 1698 was bought at the Constan-
tinople slave market by the Comte de Ferriol,
the French ambassador. She was educated at
Paris, where she was subsequently a prominent
figure in many salons. Her letters to Mme.
Calandrini were first published in 1787, with
notes by Voltaire. In 1847 a critical edition
was published by M. J. Ravenel, with a study by
Sainte-Beuve.
AISTULF, rs'tulf, or ASTOLF, iis'tolf (died
756). A king of the Lombards. He succeeded
Rachis, who entered a monastery in 749. In
752 he seized Ravenna, and soon after attempted
to capture Rome. The Pope, unable to get aid
from the Emperor at Constantinople, went to
implore assistance from Pepin (q.v.). The
latter, in 754. invaded Italy, defeated Aistulf,
and forced him to promise to give up the con-
quered territory. This Aistulf did not do, but
in January, 756, laid siege to Rome. Pepin again went to aid the Pope, besieged Aistulf, who had left Rome on learning of Pepin's advance, in Pavia. and forced him to surrender the Exarchate of Ravenna. (See Donation of Pepin.) The dates, which were disputed, are discussed and fixed in Gregorovius, City of Rome in the Middle Ages, Volume II. (London, 1896).
AITKEN, at'ken, Robert (1734-1802). A
Scotch-American printer and bookseller. He was publisher of the Pennsylvania Magazine, or American Monthly Museum, in 1775 and 1776, and in 1777 was imprisoned as a sympathizer with the Patriot cause. At a considerable loss, he printed the first American edition of the Bible (1782). He is supposed to have written An Inquiry Concerning the Principles of a Commercial System for the United States (1787).
AITKEN, William Hay Macdowall Hunter
(1841 — ). A Church of England preacher, born
in Liverpool, September 21, 1841, B.A., Oxford.
1865, M.A., 1867. Since 1877 he has been gen-
eral superintendent of the Church of England
Parochial Mission Society, which he founded in
1876. He is one of the most eminent and suc-
cessful of revival preachers. His publications
consist of sermons. In 1900 he was appointed
canon of Norwich.
AIT'KENITES. In the Church of England, the partisans of Robert Aitken (1800-73), a clergyman who had been for a time a Wesleyan, and who, after 1840, having returned to the Established Church, desired to combine with its ecclesiastical practice certain views of the Methodists, especially in regard to conversion.
AITON, ii'ton, William (1731-93) . A Scotch
botanist. He was trained as a gardener, and in 1754 became assistant to Philip Miller, superintendent of the garden at Chelsea. In 1759, he was made director of the royal botanical gardens at Kew, which he rendered the richest in existence, and held the place until his death. In 1793, he published his excellent work, Hortus Kewensis, or a Catalogue of the Plants Culti-
