Turner, Edward

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TURNER, EDWARD

(b. Kingston, Jamaica, July 1796; d. Hampstead, London, England, 12 February 1837)

analytical chemistry.

Turner was the second son of Dutton Smith Turner, a prosperous planter, and Mary Gale Redwar, a Creole of English ancestry. Her relatives raised and educated him in England. After attending Bath Grammar School he was apprenticed to a local country doctor from 1811 to 1814. He then spent two years walking the wards of the London Hospital before studying medicine at the University of Edinburgh from 1816 to 1819. At Edinburgh, where he was president of the student medical society, he formed a deep friendship with the energetic Robert Christison, a fellow medical student.

In August 1820, following an unsatisfactory attempt to practice medicine at Bath, Turner and Christison went to Paris for further study. Here Turner became attracted toward Chemistry and physics by the lectures and experimental activities of Gay-Lussac, Pelletier, and Robiquet. From the spring of 1821 until the summer of 1823 he studied mineral analysis and chemistry at Göttingen with Friedrich von Stromeyer, who had a small teaching laboratory. Encouraged by Christison, he returned to Edinburgh in 1823 and became an important private, or extramural, lecturer in chemistry, exploiting Thomas Charles Hope’s failure to provide practical chemistry teaching within the university by mounting laboratory classes. He also acted as chemical editor for David Brewster’s Edinburgh Journal of Science. In 1827, through the influence of Leonard Horner, and supported by Brewster, Christison, Hope, Jameson, and Thomas Thomson, he was appointed professor of chemistry and lecturer in geology at the new University of London (University College, London). His teaching here ensured the popularity of chemistry among London medical students and his own financial success. From the opening of classes in 1829 he held a laboratory demonstration course (assisted by Robert Warrington). The college also provided him with a small research laboratory.

An excellent lecturer, Turner enchanted his listeners, who found him gentle and easy to approach. He was always a devout Christian, but after his health broke in 1834 he underwent evangelical conversion and hoped to impart moral and religious, as well as scientific, instruction to his students. He is distinguished as the author of one of the best nineteenth-century textbooks on chemistry, for his determination of atomic weights, and for his attitude toward Prout’s hypothesis that atomic weights were integral multiples of the atomic weight of hydrogen. His many mineralogical analyses were unexceptional.

He began his career as a naīve disciple of Thomas Thomson, whose First Principles of Chemistry (1825) he admired as a work of “profound sagacity.” He was, therefore, initially convinced of the soundness of the prout-Thomson multiple weights hypothesis, although like other chemists he stressed the hypothetical character of Dalton’s atomism compared with the laws of chemical combination. His essay on this distinction (1825) was the foundation for his popular up-to-date textbook Elements of Chemistry (1827).

Through his mineralogical interests Turner was led to investigate the atomic weight of mangenese, which Thomson had determined by the precipitation reaction between mangenese sulfate and barium chloride, but which Berzelius had shown to be inaccurate. In 1828 Turner decided to place himself in the delicate position of “umpire between two of the greatest of living chemists” by investigating the discrepancies between Thomson’s and Berzelius’ atomic weights. He found immediately that Berzelius’ criticism of Thomson’s careless use of the reagent barium chloride was justified. From 1829 to 1833 he gradually showed that the remarkable edifice raised by Thomson’s Principles was a house of cards. At the meeting of the British Association for Advancement of Science held at Oxford in 1832, and at the Royal Society in 1833, Turner demonstrated by careful analyses that Thomson’s atomic weights for chlorine, nitrogen, sulfur, lead, and mercury were in serious error, that his own values confirmed those of Berzelius, and, consequently, that although integral atomic weights might be used as convenient approximations by “medical men, students, and manufactures,” the true values were inconsistent with Prout’s original hypothesis.

It is clear, however, that Turner believed (perhaps as a result of his friendship with Prout, or because of his own latent enthusiasm for mathematics) that chemists might one day find a simple relationship betwen atomic weights. He has sometimes been criticized for this wavering conclusion; but it was consistent with his empiricism and his positivistic view of physical theory. Turner believed that analytical theory. Turner believed that anlytical chemistry was open to further improvements; until such time, however, chemists had no right to make unqualified guesses either way about mathematical relationships between the elements. Turner’s emphasis upon the analyst as critical arbiter of theory, as well as his exacting standards, stimulated the later researches of F. Penny and J. S. Stas.

BIBLIOGRAPHY

I. Original Works. Forty papers by Turner are listed in the Royal Society Catalogue of Scientific Papers, VI (London, 1867–1925). His books are De Causis Febris Epidemicae nunc Edinburgi grassantis (Edinburgh, 1819), his M.D. thesis; Introduction to the Study of the Laws of Chemical Combination and the Atomic Theory (London, 1825), with German trans. (Tübingen, 1828); Elements of Chemistry (Edinburgh, 1827: 2nd ed., London, 1828, and German trans., Leipzig, 1829; 3rd ed., London, 1831; 4th ed., London, 1833, which introduced formulas; 5th ed., London, 1834). Each of these eds. received American printings. There were three posthumous eds. by J. Liebig; W. G. Turner (1811–1855), Turner’s brother,and industrial chemist; W.Gregory (London, 1842); and by Liebig and Gregory (London, 1842, 1847). Turner also published with Anthony Todd Thomson. Two Letters to the proprietors of the University of London, In Reply to Some Remarks in Mr. [G. S.] Pattison’s Statement (London, 1831), 16 pp.

For letters to Berzelius, see H. G. Söderbaum, ed., Jac. Berzelius Bref (Uppsala, 1912–1935). III. Vii 273–285. There is a small collection of Turner’s college correspondence at University College. London.

II. Secondary Literature. The most informative accounts of Turner are R. Christison, Biographical Sketch of the late Edward Turner, M.D., two eds. (Edinburgh, 1837), 36 pp.; anon., “Edward Turner,“in Gentleman’s Magazine1 (1837), 434–435; W. Whewell,”Address to the Geological Society,“in Proceedings of the Geological Society, 2 (1833–1838), 626–627; and the curious funeral sermon by Rev. Thomas Dale, The Philosopher Entering. . .the Kingdom of Heaven (London, 1837). Biographical accounts which assess his analytical work are Henry Terrey,“in Annals of Science, 2 (1937), 137–152, with portrait; and J. S.Rowe, “Chemical Studies at University College, London,“unpub. Ph.D. thesis, 1955.

W. H. Brock

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