HALES, STEPIIEN (1677-1761). An English physiologist and inventor. He was born at Beckesbourn, in Kent, and died at Teddington, in Middlesex, in 1761. He entered Corpus Christi College, Cambridge, in 1696, was elected fellow in 1702, and having taken holy orders, was pre sented about 1710 to the perpetual curacy of Teddington. He was a fellow of the Royal So ciety and trustee for the Colony of Georgia. He was the author of Statical Essays, the first part of which was published under the title of Vege 'table Staticks, or an Account of Some Statical Experiments on the Sap of Vegetables (1727), and which rapidly acquired so high a reputation as to be translated into French, German, Dutch, and Italian, and may be considered the starting point of our true knowledge of vegetable physiol ogy. A second part of this work, under the title Iltemostaticks, and treating of the circulation of the blood, appeared in 1733. In addition to
valuable researches in botany and physiology, he contributed numerous memoirs to the Philosophi cal Transactions on ventilation, on the method of keeping water fresh, on electricity, on the analy sis of the air, etc. Ventilating machines which he invented were introduced into London prisons, and were found most efficacious in diminishing mortality among the prisoners. His system was also adopted in France with similar good results. He wrote a number of essays on the evils of the drinking of spirits, which were extremely popu lar and widely circulated in the cause of tem perance. In his experiments with gases he col lected them over water, a method which was extensively employed by Priestley and other workers in the field.