GO 
COURSE OF TIIE SAP. 
[Part II. 
Here the roots must have served as more than 
“ only a point of attachment,” and the increased 
growth must have been from the soil, not from 
the air. 
But, according to Liebig, there’s nought like 
chemistry. He would do as much with his 
atmospheric chemistry as the currier with his 
leather. He generates and feeds his leaves by 
the carbonic acid of the atmosphere; and when 
he has done with them, he destroys them with 
the oxygen of the atmosphere. And he forms 
his trees by mechanical patchwork, and by 
juxtaposition, as he would a stalactite, or as he 
would the trees in the garden of a doll’s house. 
“ When the food of a plant is in greater quan¬ 
tity than its organs require for their own perfect 
development, the superfluous nutriment is not 
returned to the soil, but is employed in the 
formation of new organs. At the side of a cell, 
already formed, another cell arises. At the 
side of a twig and leaf, a new twig and a new 
leaf are developed.” 
Again: — 
u The power of absorbing nutriment from the 
atmosphere, with which the leaves of plants are 
endowed, being proportionate to the extent of 
their surface, every increase in the size and 
