ITO THE PHILOSOPHY 



the olfa£lory nerves of different animals, and fometimes of 

 different individuals of the fame fpecies, in fuch a manner as 

 to produce very different fenfations. What is pleafant to 

 the noftrils of one animal is highly offenlive to thofe of 

 another. Brute animals felecl: their food chiefly by employ- 

 ing the fenfe of fmelling, and it feldom deceives them. They 

 caiily diftinguifh noxious from falutary food ; and they care- 

 fully avoid the one, and ufe the other for nourifhment. The 

 fame thing happens with regard to the drink of animals. A 

 cow, when it can be obtained, always repairs to the cleareft 

 and frefliefl ftreams ; but a horfe, from fome infi:in£live im- 

 pulfe, uniformly raifes the mud with his feet, and renders 

 the water impure, before he drinks. 



In the fele^rtlon of food, men are greatly affifted, even in 

 the moft luxurious flate of fociety, by the fenfe of fmelling. 

 By fmeUing we often reje6l food as noxious, and will not 

 f ilk the other teft of tafting. Victuals which have a putrid 

 fmeli, as equally offenfive to our noftrils as hurtful to our 

 Gonftitutions, we avoid with abhorrence *, but we are allured 

 to eat fubftances which have a grateful and favoury odour. 

 The more frequent and more acute difcernment of brutes in 

 the exercife of this fenfe, is entirely owing to their freedom, 

 and to their ufing natural productions alone. But men in 

 fociety, by the arts of cookery, by the unnatural affemblage 

 of twenty ingredients in one difh,. blunt, corrupt, and de- 

 ceive both their fenfes of fmelling and of tafting. Were we 

 in the fame natural condition as the brutes, our fenfe of 

 fmelling would enable us to diftinguifh, with equal certainty, 

 noxious from falutary food. Brutes, as well as men, prefer 

 particular foods to others. This may be conftdered as a 

 fpecies of luxury •, but it fhould likewife be conftdered, that 

 all the articles they ufe are either animal or vegetable fub- 

 ftances in a natural ftate, neither converted into a thoufand 

 forms and qualities by the operation of fire and water, nor 

 having their favour exalted by ftimulating condiments. Do- 



