Lewis, Timothy Richards

views updated

Lewis, Timothy Richards

(b. Llanboidy, Carmarthenshire, Wales, 31 October 1841; d. Southampton, England, 7 May 1886),

tropical medicine.

Timothy Lewis, the second son of William Lewis, was born at Llanboidy but spent his early year at Crinow, a small village in Pembrokeshire, to which his family removed while he was still in his infancy. There he received his early education, first at the village school until he was ten years old, and later at a private grammar school recently opened in the locality by the Reverend James Morris, which he attended until he was fifteen. He then became apprenticed to a local pharmacist with whom he remained for four years, before moving to London. He became a compounder of medicines at the German Hospital in Dalston, London, where he became proficient in German. At the same time he attended lectures in human medicine at University College, London, where his skill in the laboratory as a chemist was quickly recognized. Subsequently, in the hospital’s wards, his intelligence and attention to detail were so marked that he was awarded the Fellowes silver medal for clinical medicine in 1866. He completed his studies at the Medical School of the University of Aberdeen, from which the received the degree of M.B. with honors in 1867.

Immediately after qualifying he applied for a commission in the army medical department and was placed first in the entrance examination for the Army Medical School at Netley, near Southampton, his name again appearing at the head of the list at the completion of the four-month course. He was commissioned successively as assistant surgeon (31 March 1868), surgeon (1 March 1873), and surgeon major (31 March 1880), and for three years before his death in 1886 he held the post of assistant professor of pathology at the Army Medical School in Netley.

Little was known of the etiology of disease, and the imagination of many investigators ran riot in hypothesis and speculation. Lewis’ work, collected and reprinted in 1888 in a commemorative volume, reveals the power of his critical examination and judgment, which enabled him to refute the wilder claims of some of his contemporaries, including such outstanding workers as Hallier, Koch, and Pasteur.

After completing the course at Netley, Lewis and D. D. Cunningham, the two best students of the session, were sent study in Germany before proceeding to India to investigate the causation of cholera. They published a series of papers, together and singly, of which Lewis’ first work, issued in 1870, on the microscopic objects found in the stools of patients with cholera, contains the first authentic account of amoebas from the human intestine. The delicate drawings (108 in all) demonstrate the care and exactitude of his observations. His interests were extremely wide, and over the next fourteen years his studies ranged over cholera, leprosy, fungal diseases, Oriental sore, bladder worms of pigs and cattle and the diets of prisoners in Indian jails. His detailed descriptions of the blood parasites of man and animals constitute his most significant contribution to knowledge and exercised a fundamental influence over the attitude of his contemporaries to the etiology of disease. His two reports on the nematode hematozoa of man and animals (1874) contain the first account of microfilariae in human blood and revealed its connection with chyluria and elephantiasis. Lewis named the hematozoon Filaria sanguinis hominis (F.S.H), later known as Filaria bancrofti. This work was originally published as an appendix to the annual report of the sanitary commissioner with the government of India and was not readily obtainable outside India. Manson, however, stumbled across it in the British Museum while on leave from China and, realizing its significance, carried out experiments on the life history of F.S.H. on his return to China in 1875. As a result he was able in 1877 to describe its development in mosquitoes.

In 1878 and 1884 Lewis published two reports on blood parasites of man and animals, including microfilarice, spirochetes in relapsing fever, and trypanosomes in the blood of rats, which was subsequently named Trypanosoma lewisi by Kent in 1880.

Two weeks before his death, Lewis was recommended by the council of the Royal Society for election as one of the fellows for 1886, but he did not live to be elected. He died of pneumonia contracted, his notebook suggests, by accidentally inoculating himself during his experiments.

Lewis’ meticulous search for pathogenic organisms in blood, feces, and urine, and his knowledge of organisms disease, unquestionably bore fruit in the discoveries of subsequent workers. As Dobell rightly pointed out, “Lewis was, like Manson, a pioneer.”

BIBLIOGRAPHY

Lewis’ writings were brought together in W. Aitken, G. E. Dobson, and A. E. Brown, eds., Physiological and Pathological Researches: Being a Reprint of the Principal Scientific Writings of the Late T. R. Lewis (London, 1888). for his journal articles, see Royal Society Catalogue of Scientific Papers, X, 584; XII, 445; and XVI, 761.

Obituaries appeared in British Medical Journal (26 June 1886), 1242-1243; Lancet (22 May 1886), 993; and Nature, 34 (1886), 76-77, with bibliography. See also C. Dobell, “T. R. Lewis,” in Parasitology,14 (1922), 413-416.

M. J. Clarkson

More From encyclopedia.com