WILLIAM

See also:

• HYDE
• HYDE, THOMAS (1636-1703)

HYDE

See also:

• WOLLASTON, WILLIAM (1659--1724)
• WILLIAM HYDE WOLLASTON (1766-1828)

WOLLASTON (1766-1828)  , English chemist and natural philosopher, was born at East Dereham, Norfolk, on the 6th of April 1766, the second of seventeen children . His father, the Rev . Francis Wollaston (1731-1815), rector of Chislehurst, grandson of the William Wollaston noticed above, was an enthusiastic astronomer . Wollaston was educated at Charterhouse, and afterwards at Caius College, Cambridge, of which he became a fellow . He took the degrees of M.B . (1787) and M.D . (1793), starting to practise medicine in 1789 at Bury St Edmunds, whence he soon removed to London . But he madelittle way, and failed to obtain a vacant physicianship at St George's hospital; the result was that he abandoned medicine and took to original research . He devoted much attention to the affairs of the Royal Society, of which he was elected a fellow in 1793, and made secretary in 18o6 . He was elected interim president in June 182o, on the death of Sir Joseph Banks; but he did not care to enter into competition with Sir Humphry Davy, and the latter was elected president at the anniversary meeting in November 1820 . Wollaston became a member of the Geological Society of London in 1812, and served frequently on the Council and for some time as a vice-president . Beyond appearing at the meetings of learned societies he took little part in public affairs; he lived alone, conducting his investigations in a deliberate and exhaustive manner, but in the most rigid seclusion, no person being admitted to his laboratory on any pretext .

Towards the

close of 1828 he felt the approach of a fatal malady—a tumour in the brain—and devoted his last days to a careful revisal of his unpublished researches and industrial processes, dictating several papers on these subjects, which were afterwards published in the Philosophical Transactions . He died in London on the 22nd of December 1828 . Most of Wollaston's original work' deals more or less directly with chemical subjects, but diverges on all sides into optics, acoustics, mineralogy, astronomy, physiology, botany and even art . In chemistry he made a speciality of the platinum metals . Platinum itself he discovered how to work on a practical scale, and he is said to have made a fortune from the secret, which, however, he disclosed in a posthumous paper (1829); and he was the first to detect the metals palladium (1804) and rhodium (18os) in crude platinum . In regard to palladium his conduct was open to criticism . He anonymously offered a quantity of the metal for sale at an instrument-maker s shop, issuing an advertisement in which some of its main properties were described . Richard Chevenix (1774–1830), a chemist, having bought some of the substance, decided after experiment that it was not a simple body as claimed, but an alloy of mercury with platinum, and in 1803 presented a paper to the Royal Society setting forth this view . As secretary, Wollaston saw this paper when it was sent in, and is said to have tried to persuade the author to withdraw it . But having failed, he allowed the paper, and also a second by Chevenix of the same tenor in 1805, to be read without avowing that it was he himself who had originally detected the metal, although he had an excellent opportunity of stating the fact in 1804 when he discussed the substance in the paper which announced the discovery of rhodium . In 1809 he proved the elementary character of columbium (niobium) and titanium . In optics he was the first, in 18o2, to observe the dark lines in the solar spectrum .

Of the seven lines he saw, he regarded the five most prominent as the natural boundaries or dividing lines of the pure simple

colours of the prismatic spectrum, which he supposed to have four primary divisions . He described the reflecting goniometer in 1809 and the camera lucida in 1812, provided microscopists with the " Wollaston doublet," and applied concavo-convex lenses to the purposes of the oculist . His cryophorus was described in 1813, in a paper " On a method of freezing at a distance." In 1821, after H . C . Oersted (1777-1851) had shown that a magnetic needle is deflected by an electric current, he attempted, in the laboratory of the Royal Institution in the presence of Humphry Davy, to convert that deflection into a continuous rotation, and also to obtain the reciprocal effect of a current rotating round a magnet . He failed in both respects, and when Michael Faraday, who overheard a portion of his conversation with Davy on the subject, was subsequently more successful, he was inclined to assert the merit of priority, to which Faraday did not admit his claim . Among his other papers may be mentioned those dealing with the formation of fairy rings (1807), a synoptic scale of chemical equivalents (1814), sounds in-audible to ordinary ears (1820), the physiology of vision (1824), the apparent direction of the eyes in a portrait (1824) and the comparison of the light of the sun with that of the moon and fixed stars (1829) . In geological circles Wollaston is famous for the medal which bears his name, and which (together with a donation fund) is annually awarded by the council of the Geological Society of London, being the result of the interest on £i000 bequeathed by Wollaston for " promoting researches concerning the mineral structure of the earth." The first award was made in 1831 . The medal is the highest honour bestowed by the society: it ,vas originally made of palladium, but is now made of gold . An appreciative essay on Wollaston will be found in George Wilson's Religio Chemici (1862) .