DECOMPOSITION OF CARBONIC ACID, ETC. 95 
the nitrogenized ferment; and that the decomposition of the 
gas occurs as a secondary result. From this we may infer 
that chlorophyll, the green coloring matter of leaves, is the 
body which in vegetables answers to the chyle of animals ; 
that it is derived from the decomposed carbonic acid through 
the eremacausis of albumen brought into the leaf, or of some 
compound of the elements of ammonia that passes up by 
the route of the ascending sap ; and that the oxygen which 
disappears, disappears to bring about the eremacausis of 
that ferment. Under this point of view, the digestion of 
plants may be regarded as taking place in the following 
way: — There is introduced into the leaf some azotized body 
formed by the aid of ammonia that has passed through the 
spongioles: on this the sunlight acts, bringing about its de- 
composition by causing its union with oxygen: and now, if 
carbonic acid be present, the decomposition is propagated 
to its atoms; a part of the oxygen set free is expended in 
continuing the eremacausis of the ferment; the rest is evolved 
with an equivalent volume of nitrogen. The carbon thus 
set free unites at once with the elements of water, and chlo- 
rophyll results. But this chlorophyll undergoes continuous 
change under the action of the sun, and is as continually 
replaced ; from it is formed gum, and finally lignin, and 
all the woody fibre of plants must have originally existed 
as chlorophyll, or passed through the green stage. 
Proceedings of the American Philosophical Society. 
