52 



same cause, namely, by the sap being di- 

 minished iQ one part, and the quantity 

 increased in another : which shows not 

 only the situation of the principal cur- 

 rent of the sap, but likewise that the sur- 

 face of the stem is enlarged in proportion 

 to its quantity. 



It would be eas}^ to multiply proofs, 

 were they necessary ; but as this is not 

 the case, we shall produce only another 

 for the present, namely, the common 

 operation of plashing or laying hedges. 

 By this operation, the whole plant is 

 made to lie in a sloping direction ; 

 often nearly flat, in consequence of a 

 deep cut, which separates almost the 

 whole of the wood, and more than half 

 the bark ; yet such plants are found not 

 only to grow, but thrive afterwards, 

 which could not have happened, ex- 

 cept the doctrine now asserted were 

 tme. 



