the field, but he was reputed to be a smart regimental officer, and to possess considerable abilities, which indeed he displayed whilst engaged at the Horse Guards previous to the war with Russia. As brigadier, he exhibited activity and intelligence in Bulgaria; and just at the moment that the expedition was about to sail to the Crimea, he was appointed to succeed Lord de Ros, in the responsible post of quartermaster-general to the forces. In that capacity he remained with the army in the East till he was called home after the fall of Sebastopol, and soon after his arrival in England he was nominated to the high military office which he now holds. The conduct of this officer whilst acting as quartermaster-general in the Crimea has been much canvassed, and grave charges have been brought against the department over which he presided, by two commissioners sent out by the government to report on certain matters connected with the commissariat of the army. He defended himself in an elaborate speech before the Chelsea commissioners; and whatever may be the opinions entertained by the public respecting the merits of his defence, or the validity of the accusations against him, it should be in fairness recollected, that he was appointed to the post of quartermaster-general under circumstances of great difficulty, and that the onerous nature of his duties was much increased by the death of Major Wellesley, who had conducted much of the details of the department. His health in the winter of 1854 was indifferent—his eyesight was imperfect, and he was unable to take that active personal superintendence of the army which an effective quartermaster-general may be expected to exercise; but he on all occasions displayed great zeal for the service, and the rewards, promotion, and honours he has received, testify to the sense entertained by the authorities of the value of his exertions.—W. H. R.
* AIRY, George Biddell, one of the first mathematicians, astronomers, and physicists now living (1859). Having entered Trinity college, Cambridge, in 1819, he gained, in 1823, the honour of senior wrangler. In 1824 he was elected a fellow of his college,—in 1826, Lucasian professor in the university,—in 1828, Plumian professor, and astronomer of the Cambridge observatory. In 1835 he was appointed by the crown to the office of astronomer-royal, which he now holds. Mr. Airy is a fellow of the Royal Society, and of various other scientific bodies, vice-president of the Astronomical Society, and a corresponding member of the Institute of France. In 1851 he enjoyed the well-deserved honour of holding the office of president of the British Association for the Advancement of Science, which in that year met at Ipswich. The following are a few amongst the many scientific achievements by which he has been distinguished:—The establishment, first at Cambridge, and afterwards at Greenwich, of an improved system of recording astronomical observations; the discovery of the "Long Inequality of Venus and the Earth," for which, in 1833, he received the gold medal of the Astronomical Society; the discovery of important principles relative to the effect of the magnetism of ships on the compass, and the means of correcting it; the investigation of the wave-theory of the tides; the determination of the laws of the circular and elliptic polarization of light in doubly-refracting crystals; the investigation of the density of the earth, by comparing the rates of a pendulum in a deep mine and at the earth's surface, &c., &c. To explain fully the nature of Mr. Airy's long series of scientific labours, and to do justice to their importance, would require an article far exceeding the limits which can reasonably be afforded in a biographical dictionary; and even were such an article now published, it would require a supplement for each additional year of the life of its subject. The following brief remarks have reference merely to a few points of general interest, in connection with those of Mr. Airy's researches which have been enumerated above. One of the distinguishing features of the system of recording astronomical observations which he introduced, is the publishing, not only of the reduced observations, corrected for refraction, for instrumental and personal errors, and for other sources of inaccuracy, but also of the original observations exactly as made, together with the various corrections applied to them. This enables every astronomer, by inspection of the published records of an observatory, to judge for himself how far the exactness of the observations, and the soundness of the methods of correcting their results, are worthy of confidence. It has further this advantage: that in the event of any new discovery being made respecting the operation of causes of errors of observation, and the methods of allowing for such errors, the benefit of that discovery can be extended to former observations, by reducing them anew. With respect to the wave-theory of the tides, it may be remarked, that Newton gave the outlines of two theories of the tides, and left it to subsequent inquirers to investigate their details, and to determine which was right. By the first theory, the ocean was considered as revolving (as it really does) round the axis of the earth once in a sidereal day, and it was proposed to determine, by the principles of dynamics, what would be the disturbing effect of the sun and moon on that motion. This may be called the dynamical theory, and is the sound one. By the second theory, well known as the "equilibrium theory," it was proposed to investigate, what form the ocean would assume by reason of the attraction of the sun or of the moon, supposing it always to present the same face towards the disturbing body. This theory is essentially unsound; but unfortunately it received the preference of Newton's immediate successors, and was developed by eminent mathematicians in very voluminous researches; and although its unsoundness has now been known to scientific men for half a century, it still holds its ground in popular manuals. Laplace was the first fully to investigate the dynamical or true theory of the tides. He arrived at the complete solution of the problem of the disturbing action of the sun and moon on the ocean, revolving in a day, as it really does; but his results were in a form too intricate and abstruse for ordinary use; and a theory was still wanting to explain the phenomena of the tides as modified by the interference of the land with the motions of the sea, especially in narrow seas, estuaries, and channels, where the motion of the waters is rather the effect of impulse transmitted from the ocean, than of the direct action of the sun and moon. Mr. Airy very much simplified the theory of the tides of the ocean, and produced a most satisfactory theory of the tides in narrow and shallow waters, by first investigating the theory of waves in water, and then applying its results to the phenomena of the tides, considered as great waves. The wave-theory of the tides is not only scientifically interesting, but of great practical utility, and well worthy of study by those concerned in the designing and execution of harbours and sea-works. Besides the papers relating to his original discoveries, Mr. Airy is the author of various treatises for the purposes of instruction in physico-mathematical science. One of the most remarkable of these is the article "Gravitation" in the Penny Cyclopædia, in which the general nature of the theory of astronomy is made clear to persons of limited mathematical knowledge, and which may be of service even to expert mathematicians, by leading them to attach clear ideas to the symbols with which they work.
AIROLA or AIROLI, Francesca, an Italian canoness and distinguished painter, of the 17th century, at Genoa. She executed several historical and sacred pictures for her native town.
AIROLDI, Paul, a Dominican of Maryland, who flourished at the beginning of the 17th century, was a popular teacher and preacher, published lectures on the Lord's Prayer, and on the seven penitential Psalms.
AISSE´, Mademoiselle, a Circassian, carried off in childhood by Turkish marauders, purchased, when four years of age, in the slave market of Constantinople by the French ambassador, and carefully educated in France, was born in 1693, and died in Paris in 1733. The romance of her life, her beauty and intelligence, her generosity of character, her high position in French society, her misfortunes, together with her letters published with notes by Voltaire, have procured her celebrity.—E. M.
AITKEN, John, lecturer on anatomy, surgery, and chemistry in Edinburgh, inventor of various important surgical instruments, and author of numerous medical works, was admitted member of the College of Surgeons in 1770, and died in 1790.
AITON, William, an eminent horticulturist, was born at a village near Hamilton, Lanarkshire, in 1731. He was educated as a gardener, and in 1754 he went to England, and became assistant to Miller (author of "The Gardener's Dictionary "), at that time superintendent of the Chelsea physic garden. In 1759 he was appointed curator of the garden at Kew, and made great improvements in it, both as regards its arrangement and the construction of conservatories. In 1789 he published a work, entitled "Hortus Kewensis," or a catalogue of the plants cultivated in the Royal Botanical Garden at Kew. In the first edition, from 5000 to 6000 plants were enumerated. They were arranged according to the Linnæan system. He secured the friendship of many eminent patrons of science, such as the Earl of Bute, Sir Joseph Banks, and Dr. Solander. He died from
