JACKSON" 495 1833 Dr. Jackson settled in Boston, and entered upon the practice of medicine, but in a few- years he abandoned it to devote himself to chemistry, mineralogy, and geology. In 1836 he was appointed geologist of Maine, and di- rected to survey that state ; and at the same time he was commissioned by Massachusetts surveyor of her public lands in Maine. In 1839 he was appointed geologist of Rhode Island, and in 1840 of New Hampshire. His surveys of these three states occupied respectively three, one, and three years, and his reports to the legislatures were published by them, with plates. Meanwhile he drew up a plan for a geological survey of the state of New York, which was adopted. In 1844 he explored the then unbroken wilderness on the southern shore of Lake Superior, and made known its mineral resources. In 1845 he again visited Lake Superior and opened mines of copper and discovered mountains of iron ore, which were explored by his assistants, and are now ex- tensively wrought. In 1847 Dr. Jackson was appointed to superintend a geological survey of the mineral lands of the United States in Michigan, and he was thus engaged for two years, when, on a change of administration at Washington, the superintendence was trans- ferred to another. His report of these labors was published in 1850, in 1 vol. 8vo. Dr. Jackson is one of the claimants of the discov- ery of anaesthetics. His claims are substantial- ly as follows : In 1834 he discovered that an alcoholic solution of chloroform, when made to act locally on a nerve, renders it insensible to pain ; and that if a piece of lint saturated with a mixture of one part of chloroform and three parts of alcohol is inserted into the cav- ity of a painful tooth, it allays the pain at once, and by repeated applications completely de- stroys the sensibility of the nerves. Having long before experimented with exhilarating gas or protoxide of nitrogen, he resumed in 1837 his experiments with that gas in order to test the comparative effects of different modes of administering it ; but the only new result he obtained was to satisfy himself that the tempo- rary insensibility which it sometimes produces is due in a greater or less degree to partial as- phyxia. Subsequently, but previous to the win- ter of 1841-'2, having received some perfectly pure sulphuric ether, he tried its effects upon himself, administering it with a mixture of at- mospheric air, and inhaled it to such an extent as to lose all consciousness, without suffering any of the dangerous or disagreeable conse- quences that had hitherto attended the inhala- tion of impure sulphuric ether unmingled with atmospheric air. In the winter of 1841-'2 he inhaled ether vapor for relief from the very se- vere pain occasioned by the accidental inhala- tion of chlorine. The relief he experienced led him to infer " that a surgical operation could be performed on a patient under the full influ- ence of sulphuric ether, without giving him any pain." Dr. Jackson's claims to the discovery 445 VOL. ix. 32 of anaesthetics, disputed by Dr. W. T. G. Mor- ton and Dr. Horace Wells, gave rise to a long controversy. In 1852 a memorial was present- ed to congress, signed by 143 physicians of Boston and its vicinity, ascribing the discovery exclusively to Dr. Jackson. About the same time the question was investigated by a com- mittee of the French academy of sciences, and on their report the academy decreed a prize of 2,500 francs to Dr. Jackson, and another of 2,500 francs to Dr. Morton. M. Elie de Beau- mont remarked in a letter to Dr. Jackson, dated May 17, 1852: "In point of fact, the academy of sciences decreed one of the Mon- tyon prizes of 2,500 francs to you for the dis- covery of etherization, and it has decreed a prize of 2,500 francs to M. Morton for the ap- plication of this discovery to surgical opera- tions." Dr. Jackson has received orders and decorations from the governments of France, Sweden, Prussia, Turkey, and Sardinia. His scientific discoveries have been very numerous. Besides the geological reports above mentioned, he has furnished many scientific communica- tions to the " American Journal of Science and Arts," to the French Comptea renchis, and to the Bulletin de la societe geologicale de France. He has also published the results of chemical researches on the cotton plant, the tobacco plant, on Indian corn, and on 38 varieties of American grapes in the United States patent office reports, and a " Manual of Etherization, with a History of the Discovery " (1863). JACKSON, John, an English painter, born at Lastingham, Yorkshire, in 1778, died in Lon- don, June 1, 1831. He was assisted in his youth by Sir George Beaumont, and acquired reputation as a portrait painter. He was re- markable for rapidity, having on one occasion for a wager painted the portraits of five gen- tlemen in a single day, for each of which he received 25 guineas. He was a royal academi- cian, and painted many of his associates. JACKSON, Samuel, an American physician, born in Philadelphia in 1787, died there, April 5, 1872. He was for 28 years professor of the institutes of medicine in the university of Pennsylvania, and occupied for a long time a leading position as a physician and surgeon. He was also popular as a lecturer, and distin- guished as a writer. His most important work is " The Principles of Medicine " (Phil- adelphia, 1832). JACKSON, Thomas, an English clergyman, born at Sancton, Yorkshire, Dec. 12, 1783, died in Richmond, March 11, 1873. He was early ap- prenticed to a carpenter, but entered the itine- rant ministry of the Wesleyan connection in 1804. After 20 years of labor in this profes- sion in Lincolnshire, Lancashire, Yorkshire, and London, in 1824 he was chosen by the British conference " connectional editor" of the Wesleyan church. He continued his edito- rial service for 19 years, when he was appoint- ed tutor in the Richmond theological institu- tion. This post he held till 1861, when he re-
