59 



reason for these productions of nature, than 

 that they are to make man industrious. 

 The stricture of tlie outer bark, however, 

 which gives rise to the greatest part of the 

 labour on fruit trees, can easily be explain- 

 ed, wifchout referring to the final cause, 

 ^i 



The outer bark forming a greater circle 

 than the inner, would require to expand 

 faster, but is prevented, being rendered 

 more rigid by exposure to the weather, and 

 is burst by the growth of the tree*. But 



* If we were to reason, or rather imagine, like the 

 medical tribe, we would not suppose that the bark was 

 burst by the growth of the tree, but that the vis medi- 

 catrix naturae brought on a spasm or constriction to 

 remove the constriction. 



