DAVY, SIR HUMPHRY, was born at Penzance, in Cornwall, on the 17th of December 1778. His ancestors had long possessed a small estate at Varfell, in the pariah of Ludgvan. His father was a carver in wood. At the time of his father's death Humphry was sixteen years old, but his mother lived to witness the rapid progress made by her son in the various departments of chemical science. In his early youth be appears to have had a vivid and fertile imagination, and his brother bee preserved several favourable specimens of his poetic talent ; other wise he showed no great precocity of talent. Under Dr. Cardew, whose school he quitted in 1793, he appears to have made considerable progress in learning, but certainly not such as gave any indication of his future eminence. In the beginning of 1795 he was apprenticed to Mr. Borlase, u surgeon and apothecary of where he appears to have laid down an extensive plan of study, not merely of the sciences which related to his profession, but the learned languages, mathematics, history, &e. Dr. Davy states that he is not able to give a precise account of the nature and extent of his medical studies ; but in the fourth year after he had commenced them he was considered competent by Dr. Beddoes to take charge of an establishment which he had founded at Bristol under the name of the Pneumatic Institution ; this was in 1798, when he was scarcely twenty years old. In the fol lowing year Dr. Beddoes published a work, entitled Contributions to Physical end Medical Ku owledge principally from the West of England.' Among these were contained 'Essays on Heat, Light, and the Combine Hone of Light, with a new Theory of Respiration; on the Generation of Oxygen Gas, and the Causes of the Colours of Organic Bodice. By liumphry Davy. Most of the peculiar views developed in thee° essays were speedily abandoned by the author; indeed his brother admits that many of the speculations, he might perhaps have said most, were wild and visionary ; and adds, what will be readily admitted, "that the wildest of them are most natural to a young mind just entering on the twilight of physical science, gifted with-high powers and a vivid imagination." His next recorded experiments relate to the existence of silica in various plants, especially in the epidermis of cane; and in 1800 be published in 1 vol. 8vo a work entitled Researches, Chemical and Philosophical, chiefly concerning Nitrous Oxide and its Respiration.' In this work, which contained the details of numerous highly-interesting experiments, he has minutely detailed the extraordinary effects pro duced both upon himself and others by respiring nitrous oxide, a gas till then deemed irrespirable. This work also contains an account of rem° extremely hazardous experiments which he made upon himself in breathing carburetted hydrogen, carbonic acid gas, emzote, hydrogen, and nitric oxide : in these dangerous trials his life was more than once nearly sacrificed.
In 1801 Davy came to London, and on the 25th of April he gave his first lecture at the Royal Institution. He began with the history of
galvanism, detailed the successive discoveries, and described the different methods of accumulating it ; and on the 31st of May 1802 he was appointed professor. From 1800 to 1807 a great variety of subjects attracted his attention, especially galvanism and electro chemical science ; the examination of astringent vegetable matter in connection with the art of tanning, and the analysis of locks and minerals with rotation to geology and to agricultural chemistry. In November 1307 his second Bakerian lecture was read, in which he announced the moat important and unexpected discovery of the decomposition of the fixed alkalis by galvanism, and of the metallic nature of their bases, to which he gave the names of potassium and sodium. Dr. Paris has well observed that "Since the account given by Newton of his first discoveries in optics, it may be questioned whether so happy and successful an instance of philosophical induction has ever beeu afforded as that by which Davy discovered the compo sition of the fixed alkalis." From the year 1S08 to 1814 the following pipers by Davy were read before the Royal Society, and published in their ' Transactions Eleetro-Chemical Researches on the position of the Earths; with Observations on the Metals obtained from the Alkaline Earths, and ou the Amalgam procured from Ammonia,' read Juno 30th,1803. ' An Account of some New Analytical Researches on the Nature of certain Bodies, the Alkalis, Phosphorus, Sulphur, Carbonaceous Matter, and the Acids hitherto uncomponnded; with some general Observations on Chemical Theory,' December 13th, 1108. ' New Analytical Remarks on the Nature of certain Bodies ; being an Appendix to the Bakerian Lecture for 1808; February 1809. Bakerian Lecture for 1809; on some New Electro-Chemical Researches on various Objects, particularly the Metallic Bodies, from the Alkalis and Earths, and on some Combinations of Hydrogen,' November 16th; 1809. ' Researches on the Oxymuriatio Acid, its Nature and Combinations, and on the Elements of Muriatic Acid; with some Experiments on Sulphur and Phosphorus,' July 12th, 1810. ' Tho Bakerian Lecture fur 1b10; on some of the Combinations of Oxymuriatio Acid Gas and Oxygen, and on the Chemical Relations of those l'riuciplee to Inflammable Bodies,' November 15th, 1810. 'On a Combination of Oxymuriatic Gas and Oxygen Gas,' February 21st, 1811. ' On some Combinations of Phosphorus and Sulphur, and on some other Subjects of Chemical Inquiry,' Juno 18th, 1812. ' On a New Detonating Compound,' November 5th, 1812. ' Some further Observations on a New Detonating Substance,' July 1st, 1813. 'Some Experiments and Observations on the Substances produced in different Chemical Processes on Floor Spar,' July 8th, 1813. 'An Account of some New Experiments on the Fluoric Compounds, with some Observe. tiona on other Objects of Chemical Inquiry,' February 13th, 1814.