OF NATURAL HISTORY. 23^ 



equal quantity of raw parfnep and potatoe in a fpliere. Af- 

 ter continuing forty-eight hours in the alimentary canal, not 

 a veftige of either remained. Pieces of apple and turnip, 

 both raw and boiled, were diiToIved in thirty- iix hours. 



It is a comfortable circumftance,' that no animal, perhaps, 

 except thofe worms which are hatched in the human intcfv 

 tines, can refift the diflblving power of the gadiic juice. 

 Dr. Stevens inclofed live leeches, and earth-worms, in dif- 

 ferent fpheres, and made the German fwallow them. When 

 the fpheres were difcharged, the animals were not only de- 

 prived of life, but completely dilTolved, by the operation 

 of this powerful menflruum. Hence, if any live reptile 

 fliould chance to be fwallowed, we have no reafon to appre- 

 hend any danger from fuch an accident. 



The German left Edinburgh before the Doctor had an 

 opportunity of making a farther progrefs in his experin^^ents. 

 He therefore had recourfe to dogs and ruminating animals. 

 In the courfe of his trials upon the folvent power in the gaf- 

 tric fluid of dogs, he found that it was capable of diffolving 

 hard bones, and even balls of ivory ; but that, in equal times, 

 very little impreilion was made upon potatoes, parfnep, and 

 other vegetable fabitances. On the contrary, in the rumi- 

 nating animals, as the fheep, the ox, &c. he difcovered, that 

 their gaftric juice fpeedily diiTolved vegetables, but made no 

 impreffion on beef, mutton, and other animal bodies. From 

 ^hefe lafi: experiments, it appears that the diiFcrent tribes of 

 animals are not lefs difilnguiihed by their external figure, 

 and by their manners, than by the quality and powers of 

 their gaftric juices. Dogs are unable to digefl vegetables, 

 and fheep and oxen cannot digefh animal fubftances. As 

 the gaftric juice of the human ftomach is capable of diiTolv- 

 ing, nearly with equal eafe, both animals and vegetables 

 this circumftance affords a ftrong and almoft an irreiiitible, 

 proof, that Nature origina^iiy jjit^nded man to feed promifcu- 

 oufly upon both. 



