Sect. III.] Theory andPradkc of Phi/sic. 315 



constantly armed when they entered inio contro- 

 versy. J3elliiii, of* Florence, as was formerly observ- 

 ed, was among thfc first medical writers who intro- 

 duced mechanical reasoning; and soon afterwards 

 the application of it was extended still liuiher by 

 profes.sor Borelli, wiio j^rosecnted the subject with 

 great learning and zeal. The laborious calculations 

 piade by these mathematicians of th(^ force exerted 

 by the heart in propelling the blood^, and by the 

 stomach in the digestion of food, are signal exam- 

 ples of the delusion which then occupied the luo.st 

 respectable minds. But no person at this period 

 seems to have proceeded farther in this course than 

 the celebrated Dr. Pitcairn, who, during some of 

 the last years of the seventeenth ceutiuy, held a 

 medical professorship in the university of Ley den. 

 He flattered himself that medical principles might 

 be supported by a clear train of mathematical 

 reasoning, which would defy the attacks of the so- 

 phist, and which would be exempt from the fluctu- 

 ations of opinion and prejudice. His works are 

 full of postulates, data, and demonstrations. And, 

 after a long parade of geometrical forms, he supposes 

 himself to have arrived at the nc plus uLlra of the 

 science of medicine f. 



* BorelU believed that he made it clearly to appear, that the 

 force of the heart is equal to 180000 pounds weight; while Dr. 

 Keil's calculation reduces the pofwer of the left ventricle to/r« 

 ounces. 



t Pictairn concludes his chrpler, De divUionc Morborum, thus 

 triumphantly : " Quapmptcrnon dubito mc .sohisse nohik probkma, 

 quod est, daU) morbo, invcnrc remvdinm, Jumquc opvs exi'Zi" Vide 

 Ekmtnta Mcdkimr Physko-Mnt/umntka, p. 177. The annaU of 

 science can scarcely furnish a more striking example of the delu- 

 tiion of enthusia'i-m, or the blindness of prejudice. 



