EFFECTS OF HEAT ON ANIMALS. 145 



venience. After they were gone, a person who had been Another did the 

 present at this experiment repeated it several times at their j*™ e repea e " 

 request with another girl, employed in attending the same 

 oven, and the results were the same. It is to be observed, 

 that a spirit thermometer was used on this occasion, which 

 gave the temperature of the oven only by approximation. 

 Tillet considered the result of these experiments as militating Tret's remark, 

 against that of Boerhaave's. It appeared to him astonish- 

 ing, that animals should have been destroyed in so short a 

 time by a temperature of 146% while women could support 

 a temperature of 264° : and he inferred, that the speedi- 

 ness of the death of those animals must be ascribed to some 

 cause foreign to the heat, such as the vitiation of the air in 

 which they were included. In consequence he made some 

 experiments, to ascertain how far Boerhaave's opinion was 

 well founded ; who, in consequence of his theory of the 

 use of respiration, attributed the fatal effects of the heat to 

 its action on the lungs alone. He exposed some animals in Exposed ani- 

 an oven heated to 156° or 166°. First he put them in na- ^550 ^j^ 

 ked, and let them remain sometime: then, having taken they bore, 

 them out, and allowed them time to recover themselves, he te " J 1 ^ 

 wrapped them up in linen cloths, which covered the whole clothed, 

 of their body, and put them in again. In the latter state 

 they supported the heat much better than in the former. 

 Hence he concluded, that the heat docs not act on the or- 

 gans of repi ration alone, but has a general effect on the 

 whole body. 



Franklin, in a letter which he wrote to Dr. Linings, pub- Franklin ob- 

 lished in the Journal de Physique for 1773, after giving an „7 his bo^ 'S 

 account of the researches he made in respect to the refri- than that of the 

 geration produced by the evaporation of fluids, endeavoured air » 

 to explain by this property a fact, which he had formerly 

 observed in himself. On a summer's day, the temperature 

 of the air being 100°, he had remarked that his own tem- 

 perature was only 96°. He was at the time lightly clothed, 

 and in a profuse perspiration. The reason of this differ- and ascribed it 

 ence of temperature he imagined therefore, to be the eva- to eva P orat,on > 

 poration going on from the surface of his body. 



In 1775, Dr. Fordyce joined with Sir Joseph Banks, Sir Experiments 

 Charles Blagdcn, Dr. Solander, and some other natural phi- b y Dr.Fordyce, 



losopherSj 



