63 



the thickness of \ to 1 a line. This contains, be- 

 sides the phosphate, about its weight of mucus, 

 which has been dried up in the earthy mass. 



Several Natural Philosophers, both ancient and 

 modern, such as STEVENS, RE AUMUR, SPALL AN- 



ZANI, SCOPOLI, BRUGNATELLI, CARMINATI, 



VAUQUELIN, &c. have endeavoured to investi- 

 gate the composition of the gastric juice; but a& 

 animal fluids in general had been little examined, 

 and the greater part of these philosophers were 

 not much acquainted with Animal Chemistry, 

 all their analytical attempts were productive of 

 no satisfactory results, since they could not com- 

 pare the substances that were found in the gas- 

 tric juice with the constituent parts of other 

 fluids. VAUQUELIN always found phosphoric 

 acid in the gastric juice of herbivorous animals; 

 whilst on the other hand, that of man and car- 

 nivorous animals, had seldom any visible trace* 

 of acid or free alkali. One of the most remark- 

 able chemical properties of the gastric juice is its 

 power of dissolving the nutriments, which the 

 animal consumes, and of coagulating milk and 

 albuminous substances. The latter requires so 

 small a quantity of the coagulating matter, that 

 YOUNG found, that if the interior mucous mem. 



