326 STUDIES OF NATURE. 



as potatoes, and other farinaceous under-ground 

 vegetables. 



Thofe adaptations of fubftance to every climate 

 are fo infallibly certain, that, in every country, 

 the fruit which is mod common there is the belt, 

 and the mod wholefome. Hence 1 farther pre- 

 fume, that fhe has followed the fame plan with re- 

 fpedt to medicinal plants ; and that having dif- 

 fufed over various families of vegetables, virtues 

 relative to our blood, to our nerves, to our hu- 

 mors, (lie has modified them in every Country, 

 conformably to the difeafes which the climate of 

 each particular country generates, and has placed 

 them in oppofition with the particular characters 

 of thofe fame difeafes. It is, in my opinion, from 

 the neglect of thefe obfervations, that fo many 

 doubts and difputes have been excited refpect,ing 

 the virtues of plants. A fimple, which, in one 

 country, is an infallible cure for a malady, may, 

 fometimes increafe it in another. The Jefuits- 

 povvder, which is the pounded bark of a fpecies of 

 frefh -water manglier of Mexico, is a remedy for 

 the fevers of America, of a kind peculiar to damp 

 and hot fituations, but frequently fails when ap- 

 plied to thofe of Europe. Every medicine is mo- 

 dified according to the place, juft as every ma- 

 lady is. 



IilraJi 



