82 



ON THE USE AND OFFICES OF THE LEAVES, &c. 



Upon what principles, and by what application 

 of power, the rise of the sap from the roots, 

 and its distribution and transformation into the 

 different parts and produce of the plant, is con- 

 ducted, is a question that has long been agi- 

 tated, and which has given rise to much spe- 

 culation, argument, and difference of opinion 

 amons: the learned. The use and office of the 

 leaves of plants, also, have been a subject as fully 

 argued and discussed, and with as little prac- 

 tical effect ; but these objects are of much more 

 importance than is generally considered by agri- 

 culturists. The nutriment being received from 

 the root into the stalk, becomes what is termed 

 the sap, and this is sent forward and appro- 

 priated to the different purposes of the plant, 

 in which process the leaves will be found to be 

 agents of great influence in determining the 

 produce. 



Many describe the sap in vegetables as circu- 

 lating, like the blood of animals, through an 

 appropriate system of vessels j wliilst others deny 



