70 CHRONICLES OF A CLAY FARM. 



ash it leaves will show you all it ever got from the 

 soil.' But the bulk, the weight, the great mass of 

 its vegetable structure where is that gone ? 



' Into the Air : 



And what seemed corporeal hath melted 

 Like breath into the wind ! ' 



The weight, the bulk, the vegetable mass, of a 

 crop, is simply, its Carbon. COMBUSTION just un- 

 does what GROWTH did : and nothing more. It 

 recombines the Carbon of the plant with the Oxygen 

 of the air, and their union is Carbonic-acid gas, the 

 very substance which the leaves of a plant feed upon 

 in the air, where it is presented to them in its gaseous 

 form, in which alone they can absorb it : they do ab- 

 sorb it ; and in their clever little laboratory they pick 

 out the carbon, and return the oxygen ; just as our 

 own lungs take up the oxygen and return the nitrogen. 

 Multiply the two sides of an oak-leaf by the number 

 of leaves on the tree, and you will be able to form 

 some idea of the extent of surface, which the plant 

 annually presents to the atmosphere to carry on this 

 work of absorption. 



But the roots what is their use then ? 



Examine them through a Microscope, and you will 

 see that, as the Leaves are adapted to intercourse 



