190 -LETTERS TO BROTHER JOHN. 



tion, there are still animals which they have not 

 yet been able to preserve alive much less in 

 health ! You cannot withdraw the leopard from his 

 jungle and his tropical climate, and turn him adrift 

 on the plains of Siberia, with impunity to himself: 

 nor will the cedars of Lebanon nourish on the bar- 

 ren hills of the frozen North. 



As it is with habits, so with food. All animals 

 cannot subsist upon the same food indifferently : 

 nor all vegetables upon the same soil. A dog will 

 not thrive on oats, nor a horse on beef; nor a cat 

 on green gooseberries. Nay, all animals, even of 

 the same species, will not thrive equally well on 

 the same food. There is a race of horses some- 

 where, I think, in Tartary who are fed wholly on 

 camel's milk. If it be attempted to make them 

 subsist on coru, they sicken, and die. 



Seeing, then, that every other system in the 

 universe has its natural sphere of existence its 

 natural habitudes, from which it cannot be removed 

 without injury it seems only in accordance with 

 strict analogy, to suppose that man also has a 

 sphere of existence and certain habitudes natural 

 to himself; and that he cannot withdraw himself 

 from this sphere and these habitudes, without in- 

 jury to the perfection of his nature. 



