HALES, STEPHEN
761), English physiologist, chemist and inventor, was born at Bekesbourne, Kent, in Sept. 1677. He took holy orders at Cambridge, and in 1708 was pre sented to the perpetual curacy of Teddington, Middlesex, where he remained all his life, though he subsequently held the rectories of Porlock, Somerset and of Faringdon, Hampshire. In 1717 he was elected fellow of the Royal Society, which awarded him the Copley medal in 1739, and on the death of Sir Hans Sloane in 1753, Hales was chosen foreign associate of the French Academy of Sciences. He died at Teddington on Jan. 4, 1 7 61.
Statical Essays. The first volume, Vegetable Staticks (1727), describes experiments in plant-physi ology : transpiration, the rate of growth of shoots and leaves, va riations in root-force at different times of the day and the nour ishment taken in by plants from the air. In his experiments he was able to collect gases over water in vessels separate from those in which they were generated, and thus used what was to all in tents a "pneumatic trough." The second volume (1733) on Haemo staticks, contains important experiments on the mechanical rela tions of blood-pressure, the velocity of the current and the capacity of the different vessels. With Robert Whytt, Hales showed the necessity of the spinal cord for reflex movements. He also devised a "ventilator" (a modified organ-bellows) by which fresh air could be conveyed into gaols, hospitals and ships'-holds, and invented a "sea-gauge" for sounding, and processes for dis tilling fresh from sea water, for preserving corn from weevils by fumigation with brimstone, for salting animals whole by passing brine into their arteries and for bottling chalybeate waters. His Admonition to the Drinkers of Gin, Brandy, etc., was published anonymously in 1734.
