96 HUTTON of the Product and Powers of Numbers " (Lon- don, 1781); "Mathematical Tables" (1785); "Course of Mathematics" (3 vols., 1793); and " Mathematical and Philosophical Dictionary " (2 vols. 4to, 1795). He was also for many years editor of the "Ladies' Diary." BUTTON, James, a British natural philoso- pher, born in Edinburgh, June 3, 1726, died March 26, 1797. He entered the university of Edinburgh in 1740, and began the study of law, which he subsequently abandoned for medicine, taking the degree of M. D. at Ley- den in 1749. He engaged in the manufacture of sal ammoniac from coal soot, inherited from his father a small estate in Berwickshire, be- took himself to agriculture, finally removed to his native city in 1768, devoting himself es- pecially to the study of geology, and made sev- eral important discoveries. In 1795 he pub- lished the results of 30 years' study in his " Theory of the Earth," assuming that heat is the principal agent of nature. HUXLEY, Thomas Henry, an English natural- ist, bora in Baling, Middlesex, May 4, 1825. He spent two and a half years at Baling school, in which his father was one of the masters, but with this exception his education was carried on chiefly at home. In 1842 he entered the medical school of Charing Cross hospital, and in 1845 received the degree of M. B. from the university of London, being placed second in the list of honors for anatomy and physiology. He began his literary career while yet a student by contributing to the " Medical Times and Gazette" a paper on that layer in the root sheath of hair which has since borne his name. In 1846 he joined the medical service of the royal navy, and was stationed at Haslar hospi- tal, whence he was selected the same year to accompany Capt. Stanley, as assistant surgeon of the Rattlesnake, in his expedition to the South Pacific. After a four years' voyage of circumnavigation, during which surveys of the east coasts. of Australia and Papua were made, the ship returned to England in November, 1850. While absent Mr. Huxley, who made extensive observations on the natural history of the seas traversed, sent home a number of communications, the first of which, read before the royal society in 1849, is " On the Anatomy and Affinities of the Family of the Medusae." On his return some of these papers were elab- orated by him and published in the "Philo- sophical Transactions" of the royal society, of which, in June, 1851, he was elected a fellow. In 1853 he resigned his position in the navy, and in the following year he succeeded Prof. Edward Forbes as professor of natural history in the royal school of mines, an office which he still holds (1874). He has since resided in London, where he has devoted himself to constant scientific labor and research. In ad- dition to his annual course of lectures on gen- eral natural history, he has delivered many lectures on kindred subjects to mixed audi- ences, and has done much to popularize sci- HUXLEY
ence. He was Hunterian professor in the royal college of surgeons from 1863 to 1869, and was twice chosen Fullerian professor of physiology in the royal institution. In 1869 and 1870 he was president both of the geologi- cal and the ethnological society ; in 1870 he was president of the British association for the advancement of science ; and in 1872 he be- came secretary of the royal society. Since 1870 he has been a member of the royal com- mission on scientific instruction and the ad- vancement of science. From 1870 to 1872 he served on the London school board, where he was chairman of the committee which drew up the scheme of education adopted in the board schools. During this time he took an active part in its deliberations, and became conspicu- ous by his opposition to denominational teach- ing, and particularly by his denunciation of the doctrines of the Roman Catholic church. In 1872 he was elected lord rector of the univer- sity of Aberdeen. Prof. Huxley has done as much probably as any living investigator to advance the science of zoology, and the world is indebted to him for many important discov- eries in each of the larger divisions of the ani- mal kingdom. His earlier labors were devoted chiefly to the lower marine animals, with which he formed a most thorough empirical acquaint- ance during his Pacific voyage, and he has described many which previously had been either unknown or very imperfectly studied. During the past ten years he has devoted him- self assiduously to the comparative anatomy and the classification of the vertebrata, and has embodied the results of his more important researches in numerous monographs. In his first published work, on the medusa?, he called attention to the fact that the body of these animals is formed of two cell layers, which may be compared to the two germinal layers of the higher animals ; an idea which has since found its complete expression in the gastraaa theory of Haeckel. To him also is due the vertebral theory of the skull, which has since been de- monstrated so clearly by Gegenbaur ; and he was the first to extend to man Darwin's theory of natural selection. In his three lectures on " Man's Place in Nature," delivered in 1863, he made an elaborate exposition of the doctrine of evolution as applied to man, asserting that the anatomical differences between man and the highest apes are of less value than those between the highest and the lowest apes. Among his many popular lectures, that " On the Physical Basis of Life," delivered in 1868, has attracted much attention. In it he ad- vances the idea that there is some one kind of matter common to all living beings ; that this matter, which he designates as protoplasm, depends on the preexistence of certain com- pounds, carbonic acid, water, and ammonia, which when brought together under certain conditions give rise to it ; that this protoplasm is the formal basis of all life, and therefore all living powers are cognate, and all living forms,
