The Birth of Titrimetry: William Lewis and the Analysis of American Potashes

William Lewis (17081781), was a physician, author, and an experimental chemist. Sometime after 1730 he gave public lectures in London on chemistry and the improvement of pharmacy and manufacturing arts (1). With a growing reputation as a chemical experimentalist he was elected F.R.S., on October 31,1745, and was then living in Dover Street, London. In 1747 he moved to Kingston-uponThames, where he set up a well-equipped laboratory and presumably continued in medical practice. From about 1750 until his death in 1781 Lewis employed Alexander Chisholm as his assistant in chemical and literary works (2). These improved the knowledge and practice of pharmacy, but as a practical consulting chemist Lewis has received little biographical recognition. He was awarded the Copley Medal by the Royal Society in 1754 for researches on platina (platinum), which he claimed was a distinct metal, and for devising methods of chemical identification. These results were published in Philosophical Transactions, 1754 and 1757 (3). THE BIRTH OF TITRIMETRY: WILLIAM LEWIS AND THE ANALYSIS OF AMERICAN POTASHES