London: Printed for W. and J. Innys, 1727; 1733. Two volumes: 8to. [vii], [i], vii, [ii], 376; [i-v],vi-xxii, , 1-361,  pp. FIRST EDITIONS. Each volume complete with blanks and index. Volume I with 19 plates by S. Gribelin. Contemporary Cambridge-style paneled calf, gilt spines with black labels. An unusually fine and clean copy of both volumes. Volume I with contemporary signature of J. Belson? and more modern one of John Knowles; Volume II with contemporary signature of Oliver W. Casland and a later signature of John Knott, M.D., as well as bookplate of Myron Prinzmetal. Item #14447
First edition of both volumes. The first is Hales’ classic on the physiology of plants. His many experiments with gases led him to demonstrate the dependence of plants on air. He was the first to realize that carbon dioxide was supplied to plants by air, and that it formed a vital part of the plant’s food supply. He also measured the amount of water taken up by plants and the transpiration of the leaves. His investigations on the circulation of the sap in plants and on their life generally are of fundamental importance. “These experiments led the way to those of Ingenhousz and de Saussure, while his ideas on combustion and respiration facilitated the discoveries of Black, Lavoisier and Priestley” (Printing and the Mind of Man, 189a).
Volume II details Hales’ pioneer invention of the manometer, with which he was the first to measure blood pressure. “His work is the greatest single contribution to our knowledge of the vascular system after Harvey, and led to the development of blood-pressure measuring instruments now in universal use” (Garrison, History of Medicine, p. 322). Hales was also the first physiologist to suggest that electricity plays a role in neuromuscular phenomena.
Hales (1677-1761), botanist, physiologist and chemist, was a member of the Royal Society and winner of the Copley Medal.