Sect. II.] Physhlogi/. 305 



other tribes of animals which possess asimiiar orga- 

 nization of this viscus, it is cilbcted by the solvent 

 operation of the gastric fhiid independently of tri- 

 turation. 



Beside the points in physiology already noticed, 

 many others might be mentioned which have un- 

 doubtedly received much elucidation and improve- 

 Jiient in tlie course of tiie late century. The senses 

 of Vision and Hearing, which had previously de- 

 rived a great deal of light from the endeavours used 

 to investigate them, have been examined with still 

 more minuteness and success within the last hun- 

 dred years, and many new facts and princii>Ies con- 

 cerning them have been satisfactorily ascertained. 

 But the doctrines of Secretion and Nutrition, thouirh 

 so fundamental in a thorough acquaintance with 

 the animal economy, notwitlistanding all the dili- 

 gence and ingenuity bestowed on them by a mul- 

 titude of physiologists, have not been cultivated 

 with equal success, and indeed can scarcely be 

 said to be better understood at ' this time than 

 they were at the close of the seventeenth cen- 

 tury. 



The celebrated doctrine of the vitalitj/ of the 

 blood, which Avas first distinctly taught in modern 

 times by Harvey, found a new and able advocate 

 in Mr. John Hunter, who maintained, in his lec- 

 tures, that the fluids as well as the solids were pos- 

 sessed of the principle of life. The arguments by 

 which he endeavoured to support this doctrine are 

 not only ingenious and forcible in themselves, but 

 they derive additional strength from the theory of 

 respiration, and the principles ol' pncunuitic che- 

 mistry, which are now generally received. 

 Vol. I. X " 



