314 J. LeConte on the Correlation of Forces. 
evidently supplementary. The decomposition of CO, by sun- 
light may be considered as the original source of all vegetation, 
ung the necessary force. portion of the organic matter, falling 
from the organic to the mineral plane, sets free a force which 
raises the ining portion into a slightly higher condition 
—_ of animal life, and as such has passed into the 
wens © | y. 
38 in a state of unstable equilibrium; that constant decompos! 
is the result of this instability, and that 
