PHANTOM FLOWERS. 77 



moisture every twelve hours, or seventeen times more 

 than a man. 



These facts prove that the greater portion of the 

 crude liquids which are taken up by the roots of a 

 plant, passes off into the atmosphere through the leaves. 

 The quantity of moisture thus appropriated by some 

 plants must be enormous, as the foregoing experi- 

 ments with small ones sufiiciently prove. Large trees, 

 presenting a great expanse of foliage, must necessarily 

 exhale immense amounts of moisture. Thus, forest 

 lands which are wet, and even swampy, become dry 

 on being cleared. G-ardens which are unduly crowded, 

 are generally damp from the copious exhalations pro- 

 ceeding from excessive foliage. From the same cause 

 proceeds the dampness in houses whose exterior is 

 enveloped by shrubs or running vines. 



From the large proportion of mineral matter con- 

 tained in the leaves, it is evident that the same sub- 

 stances existing in the earth must be annually circula- 

 ting from one to the other. The roots extract them 

 from the soil, they ascend the tree with the sap, and 

 are deposited in the leaves. Having given them co- 

 herency and strength, and having probably performed 

 other functions which are yet unknown to either 

 botanist or chemist, the fall and decay of the leaves 

 7* 



