340 HISTORICAL AND COMPARATIVE. 



acceleration of the blood-stream in the inflamed part, and owing to the swelling (tumor) from 

 the presence of good heat-conducting fluids ; but the heat is not greater than the heat of the 

 blood. It is not proved that an increased amount of heat is produced owing to increased 

 molecular decompositions within an inflamed part. 



228/HISTORICAL AND COMPARATIVE. According to Aristotle, the heart prepares 

 the heat within itself, and sends it along with the blood to all parts of the body. This 

 doctrine prevailed in the time of Hippocrates and Galen, and occurs even in Cartesius and 

 Bartholinus (1667, " flammula cordis "). The iatro-mechanical school (Boerhave, van Svrietcn) 

 ascribed the heat to the friction of the blood on the walls of the vessels. The iatro- chemical 

 school, on the other hand, sought the source of heat in the fermentations that arose from the 

 I>assage of the absorbed substances into the blood {van Hclmont, Sylvius, Ettmiillcr). Lavoisier 

 (1777) was the first to ascribe the heat to the combustion of carbon in the lungs. After the 

 construction of the thermometer by Galileo, Sanctorius (1626) made the first thermometric 

 observations on sick persons, while the first calorimctric observations were made by Lavoisier 

 and Laplace. Comparative observations are given at 207, and also under Hybernation ( 

 225). 



