100 FOURTH REPORT 1834. 



Aristotle, four elements ; tuid deduced, from the various propor- 

 tions and mixtures of these, the elementary particles of the frame ; 

 and secondary qualities, or cardinal humours founded on the 

 greater or less prevalence of one or other of the elementary princi- 

 ples, not greatly differing in this respect from Hippocrates. Ac- 

 cording to Galen, Nature presides over the vegetative, and the 

 soul over the voluntive faculties*. 



The theory of Galen prevailed through many successive cen- 

 turies, its unestablished and mystical parts prevailing more or 

 less over those which were founded on experience and reason, ac- 

 cording to the degree of light and the character of the teachers 

 during that long lapse of time so much disfigured by ignorance 

 and barbarism. 



At length, in the seventeenth century, Harvey's great dis- 

 covery of the circulation of the blood gave an importance to ana- 

 tomical inquiry which the successive and valuable contributions 

 it had hitherto received had failed to bestow ; whilst the dis- 

 coveries of Hooke and of Boyle in pneumatic chemistry turned 

 men's minds to study with increased ardour the minute details 

 of every function, and to apply to the solution of the problem of 

 life all those analogies which the advance of science in every di- 

 rection so liberally afforded. Hence arose the chemical and the 

 mathematical schools of physiology to eminence. The first in- 

 cludes the names of Van Helmont, Sylvius, Willis, John Mayo, 

 Croone, Helvetius. Its insufficiency was exposed byBoerhaave, 

 Hoffmann, and Pitcairne, and in this country practically by Sy- 

 denham. 



The mathematical school of physiology gained a better recep- 

 tion. Its doctrines, recommended by the prevalence of the atomic 

 theory of Descartes, gave the same direction to physiology and 

 medicine with that in which science Avas principally advancing 

 under the auspices of the Florentine Academy. The philosophy 

 of Descartes appeared peculiarly applicable to such investiga- 

 tions, since no reason apparently could be assigned which should 

 render that law inapplicable to organic bodies which referred all 

 changes in matter generally to the figure and motion of the ulti- 

 mate particles of which they were composed f. Hence Ave find 

 the followers of Descartes representing in their works, the mathe- 

 matical forms of the ultimate particles, of which they supposed 

 the various organs to be composed, as figures for the application 

 of mathematical reasoning. The most distinguished disciple of 

 this scliool was Borelli. He united to all the anatomical infor- 

 mation of the day a depth of mathematical knowledge which 

 enabled him, in appearance, to apply its reasonings and its results 



* Thompson's Life of Cnllen. t Ibid. 



