Food. 33Y 



I must allow them to be in the argument,) will by no means solve the 

 apparent paradox of the Horse's becoming fat from eating the cooked, 

 and lean from the use of the raw potatoe ; inasmuch as the nature 

 and quantity of their work, was in both cases the same. The facts which 

 have been already related prove, indeed, that the gastric juice is 

 not always of the same kind, in the same animal ; for it has been shewn 

 tliijit such animals as are instinctively carnivorous, may be brought ^o 

 subsist on vegetable food, and vice versa, but then if the change to 

 the creature's natural diet, be made suddenly, it will fall away or die, 

 in consequence of inability to digest that very food, which it was 

 instinctively taught to prefer. Now, a sort of modification of this 

 principle, undoubtedly applies to the case before us, for, though 

 the difference between raw and cooked food of the same kind, can 

 by no means be compared to that which exists between vegetable 

 food and animal, yet this circumstance must not be overlooked in 

 our endeavours to account for effects of such a curious kind. But, 

 the solution of this apparent difficulty, must be sought for, in the 

 culinary process, which renders the potatoe a very different article 

 of food for animals as well as man, from what that root is, in its raw 

 state. The mode, however, in which cooking effects the change in 

 the potatoe, so favourable to digestion, admits not of any very 

 decisive or satisfactory explanation. I am afraid we must content 

 ourselves with the knowledge of the bare fact, until we are enabled 

 to develop in some degree, the mysterious nature of digestion. 

 Nevertheless, it is certain that coction produces some chemical change 

 in the potatoe, for, the juice which may be separated from boiled pota- 

 toes, is sweet-tasted, which is not the case with the raw juice. Some 

 change, therefore^ similar to that which is brought about in corn hy 



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