28 



We see the miraculous and universal 

 system of transubstantiation with which 

 we are surrounded in the vegetable world, 

 yet we are not only ignorant of the 

 cJiemistry which produces it, — which, from 

 absorbed moisture and gases, forms all 

 the various woods, bark, leaves, flowers, 

 scents, fruits, seeds, &c. of that most 

 exquisite kingdom, — but we are even 

 ignorant in what part of the plant the 

 elaboration takes place, or from what part 

 of the plant the new growth is deposited. 



Whether any chemical change or elabo- 

 ration of the sap really does take place in 

 the leaf I shall not question ; but I think 

 that possibly the leaf only gives off the 

 supernumerary watery parts necessary to 

 take up and conduct to their destination 

 the carbonic acid, ammonia, and inorganic 

 matters requisite for vegetable life, and 

 that it exhales the unnecessary gases, &c. 

 after the decomposition of the constituents 

 absorbed from the soil. Certainly the 



