HENRY, WILLIAM, was the son of Mr. Thomas Henry of Man chester, who was a zealous cultivator of chemical science. Dr. Henry was born on the 12th of December 1775. His earliest instructor was the Rev, Ralph Harrison, who on the establishment of an academy io Manchester, afterwards removed to York, was chosen to fill the chair of classical literature. Immediately after leaving the academy he became an inmate in the bonne of Dr. Percival, whose character as an able and enlightened physician is well known. Here he remained for some years, and in 1795 he studied at Edinburgh, where the chair of chemistry was occupied by the venerable Dr. Black. After remaining there only one year however, he was obliged from prudential motives to quit the university. On visiting Edinburgh again in 1807 ho received the diploma of Doctor in Medicine, and although he subse quently and successfully practised as a physician in Manchester, he was compelled to retire from it on account of the state of his health, I which from an accident in early life bad always been delicate.
Though the period between his two academical residences was passed in the engrossing occupations of his profession, and the superintend epee of a chemical business established by his father, ho nevertheless both zealously and auceeaofully attended to the science of chemistry, an'd from that period until 1836, the year in which he died, he con tributed a great number of important papers to the Royal Society, the Society of Manchester, and to various philosophical journals. In 1797 he communicated to the Royal Society an experi mental memoir, the design of which was to re-establish, in opposition to the conclusions drawn by Dr. Austin, and sanctioned by the approval of Dr. Beddoes aud other eminent chemists, the title of carbon to be ranked among elementary bodies, although his proofs indeed contained a fallacy, which in a subsequent paper ho himself corrected. In 1800 ho published in the 'Philosophical Transactions ' researches on muriatio acid gas. These experiments were undertaken in the hopes of detaching the imaginary element, which, in accordance with the prevailing theory, was supposed with oxygen to constitute the acid in question. It was not till many years afterwards that the true nature of this acid was ascertained by Davy, and to the new doctrine Dr. Henry was an early
convert.
In 1803 Dr. Henry made known to the Royal Society his elaborate experiments on the quantity of gases absorbed by water at different temperatures, and he arrived at the simple law, "that water takes up of gas condensed by one, two, or more additional atmospheres, a quantity which ordinarily compressed would be equal to twice, thrice, &c., the volume absorbed under the common pressure of the atmos phere." In 1808 he published in the same work a form of apparatus adapted to the cotubuetion of larger quantities of gas than could be fired in cudiometric tubes. In the same year he was elected a Fellow of the Royal Society, aud in the year following he received, by the award of the president and council, Sir Godfrey Copley's donation, as a mark of their approbation of his valuable communications to the society. Ile published various other papers, both in the 'Manchester Memoirs' and in the 'Philosophical Transactions.' His latest com munication to the Royal Society was a paper in 1824, in which he succeeded in overcoming tho only difficulty he had not before con quered, that of 'ascertaining by chemical means the exact proportions which the gases left after the notion of chlorine on oil and coal gas bear to each other. This he effected by availiug himself of the property which had been recently discovered by Doberciner in finely divided pietism, of determining gaseous combination. All his com munications afford admirable examples of inductive research, great philosophical acumen, and almost unequalled precision in manipulating. Dr. Henry was also the author of a most valuable and useful work, entitled Elements of Experimental Chemistry,' which has reached the eleventh edition. He was a man of great general information, and considerable literary attaiomeuts and ability, as shown by the very superior style of his scientific papers. In his private character he was in every respect estimable.
Dr. Henry'e frame, originally delicate, worn out by illness and dis tracted by loss of sleep, at last gave way, and he died on the 2nd of September 1836 in his sixty-first year.