Lewis, William

(b. Richmond, Surrey, England, 1708; d. Kingston, Surrey, England, 21 January 1781),

chemistry, pharmacy, chemical technology.

Born into a brewing family in the environs of London, Lewis had an early opportunity to observe rudimentary chemical technology. By the time he had spent some five year at Oxford (1725-1730) and graduated M.B. from Cambridge in 1731, he had acquired a definite interest in the chemical arts. He was giving public lectures in chemistry “with a View to the Improvement of Pharmacy, Trades and the Art itself” at least as early as 1737. Within a few years he had established sufficient reputation to be elected a member of the Royal Society in October 1745, and he remained a part of the London scientific scene for the rest of his life.

Whatever Lewis learned at Newtonian Oxford and Cambridge was supplemented and shaped by later editorial labors on authors less devoted to the mechanical philosophy. His practical bent was nurtured by his 1746 edition of George Wilson’s venerable Compleat Course of Chemistry and by his abridgement in the same year of the Edinburgh Medical Essays. The latter included many articles reflecting the long-term interests of the Edinburgh physicians in the practical chemistry associated with materia medica and mineral waters. Lewis’ own interest in applied chemistry never waned, and, after he moved westward out of London proper to the village of Kingston in 1746, he continued to work on pharmacy and materia medica, gradually expanding his interests to include other areas of chemical technology.

That his plan for a broadly based attack on problems in applied chemistry was formed fairly early is suggested by his published pamphlet of 1748 proposing a periodical entitled commercium philosophicotechnicum. As planned, this new publication was to examine various manufacturing processes systematically, through laboratory studies where necessary, and to eliminate wasteful procedures and products. Lewis was far from alone in these interests. Many men of commerce and learning felt the need for the practical improvements in the arts that were promised but never delivered by the enthusiasts of the new mechanical philosophy. Indeed, this period saw the rise of several groups interested in such improvements, notably the Royal Society of Arts (founded 1754) and the Lunar Society of Birmingham. Lewis himself had a broad circle of acquaintances with similar outlooks, and he availed himself of their opinions of his projects on a number of recorded occasions.

While his broad plan for applied chemistry was thus being formulated, Lewis kept up his pharmaceutical activities. He had agreed to produce a new English pharmacopoeia and, perhaps as preparation for this task, translated the fourth Latin edition of the Edinburgh Pharmacopoeia and published it in 1748.

One of the most significant events in Lewis’ life occurred in 1750, when he began his lifelong association with Alexander Chisholm. Searching for an intelligent and educated assistant for his numerous projects, Lewis found one, appropriately enough, in a London bookstore. Their careers, until Lewis’ death, were inseparably entwined; to speak of one is to speak of the other. Chisholm, who in 1743 had graduated M.A. from Marischal College, Aberdeen, was an able linguist, competent in Latin and Greek and in the German and Swedish vernaculars. Indeed, it is believed that the translation of Caspar Neumann’s chemical lectures was done by Chisholm.

Lewis’ long-standing interest in materia medica and his studies of previous works in pharmacy, including his translation of the Edinburgh Pharmacopoeia, culminated in 1753 with was publication of The New Dispensatory, which was based on Quincy’s Complete English Dispensatory. Careful and systematic, like all of Lewis’ works, the New Dispensatory was highly praised by that archcritic William Cullen as the only English pharmacopoeia that “made any improvement on the Materia Medica….” The work went through many editions before and after Lewis’ death, and its spirit was retained in the form and arrangement of Andrew Duncan’s Edinburgh New Dispensatory (1803), which survived well into the nineteenth century.

Perhaps no work better shows Lewis’ abilities as an experimentalist than his series of researches on platinum during the 1750’s. Although others had attacked this intractable metal before him, using a number of standard metallurgical techniques, Lewis succeeded where others had failed through his careful systematic approach and the clever use of chemical analogy. Well-versed in the trends of his time, Lewis quickly turned to acids to get the metal into solution. Noting certain similarities between platinum and gold, Lewis defined the new metal in terms of an old one whose chemistry was relatively well understood. In his knowledge of solution chemistry and his ability to employ it imaginatively, Lewis showed himself to be in the forefront of eighteenth-century experimental chemistry. For this effort and for his already substantial contributions to pharmacy and materia medica Lewis was awarded the Copley Medal of the Royal Society in 1754.

Attracted by the empiricism bias of the work of the German chemist and apothecary Caspar Neumann, Lewis published in 1759 a translation with both additions and abridgments of Neumann’s chemical lectures. Neumann’s approach presents a strong contrast to George Wilson’s stark collection of recipes; for the former, although cautious as a theoretician, was a follower of Georg Ernst Stahl, and thus his work employed the complex of ideas associated with the “inflammable principle”—phologiston. Much has been made of Lewis’ description of Neumann as “biassed by no theory and attached to no opinions.” That Lewis would hold such an opinion would literally mean that he had never read Neumann, for there is no possible doubt where the latter’s theoretical sympathies lay. What Lewis undoubtedly objected to was the preconceived and—to him as well as to other practical chemists like Robert Dossie—ill-conceived notions of the corpuscularians. Like most of his contemporaries, Lewis felt free to accept or reject the various dicta associated with the phlogiston concept. His interests lay in the determination of chemical composition, a task that Stahl and such followers as Neumann were certainly better equipped to handle than the Newtonian chemists. Lewis himself used the other pillar of phlogiston chemistry—affinity—with ease, even though, like many others, he was not overly concerned with the corpuscular details of this theory.

Certainly Lewis’ most ambitious work was the Commercium philosophico-technicum, which appeared in sections over the period 1763-1765. He divided the book into seven topics that by no means form a complete survey of chemical technology of this period. The topics included such diverse headings as the chemistry of gold, vitrification, expansion and contraction of bodies with change in temperature, blowing air into furnaces by the force of falling water, methods of producing the color black, and a summation of Lewis’ studies on platinum. While these topics differed widely in their immediate applicability to technology, as a group they demonstrated forcefully the possibility of relating chemical knowledge to a wide variety of industrial problems.

Although Lewis was prolific, his general way of working was slow and methodical. He read extensively, took notes and made additions to them from his own experience, and even conducted new experiments to confirm or deny the claims of others. But it must not be assumed that his only virtue was his systematic methodology. His skepticism about the “mechanical philosophy” was in itself a philosophical position, one which was shared by a substantial number of his contemporaries. In his later works, and particularly in the highly empirical Commercium philosophicotechnicum, he eschewed a simple empirical approach—such as descriptions of manufactures or histories of processes—for one that was based on the “invariable properties of matter.” What Lewis avoided was a dependence on the sterile mechanical philosophy that promised so much and produced so little in chemistry.

BIBLIOGRAPHY

I. Original Works. Lewis’ works are A Course of Practical Chemistry in Which are Contained All the Operations Described in Wilson’s Complete Course of Chemistry (London, 1746); Medical Essays & Observations, published by a society in Edinburgh, in six volumes, abridged and disposed under general heads (2 vols., London, 1746); Pharmacopoeia of the Royal College of Physicians of Edinburgh (London, 1748); Proposals for Printing, by Subscription, Commercium philosophico-stechnicum or The Philosophical Commerce of the Arts (London, 1748); Oratio in theatro Sheldoniano, habilo idibus Aprilis (Oxford, 1749); An Answer to the Serious Inquiry Into Some Proceedings Relating to the University of Oxford (London, 1751); The New Dispensatory… Intended as a Correction and Improvement of Quincy (London, 1753; 6th ed., 1799); “Experimental Examination of a White Metallic Substance…,” in Philosophical Transactions, 48 , pt. 2(1754), 638-689; “Experimental Examination of Platina,” ibid.,50 , pt. 1 (1757), 148-166; The Chemical Works of Caspar Neumann (London, 1759); Experimental History of the Materia Medica (London, 1761; 3rd ed., 1769); Commercium philosophico-technicum or The Philosophical Comme rce of Arts: Designed as an Attempt to Improve Arts, Trades and Manufactures(London, 1763-1765); Experiments and Observations on American Potashes (London, 1767); and the posthumous A System of the Practice of Medicine, From the Latin of Dr. Hoffmann By the Late William Lewis (London, 1783).

II. Secondary Literature. See F. W. Gibbs, “William Lewis, M.B., F.R.S. (1708-1781),” in Annals of Science, 8 (1952), 122-151; Edward Kremers, “William Lewis,” in Journal of the American Pharmaceutical Association, 20 (1931), 1204-1209; and Nathan Sivin, “William Lewis (1708-1781) As A Chemist,” in Chymia, 8 (1962), 63-88.

Jon Eklund