Prof. LeConte on the Correlation of Forces. 143 
antagonistic forces, chemical and vital; the former constantly 
tearing down and destroying, the latter as constantly building 
up and repairing the breach. In this unnatural warfare the che- 
mical forces are constantly victorious, so that the vital forces are 
driven to the necessity of contenting themselves with the simple 
work of reparation. As cell after cell is destroyed by chemical 
forees, others are put in their place by vital forces, until finall 
the vital forces give up the unequal contest, and death is the 
result. I do not know if this view is held by the best scientific 
minds at the present day as a fact, but it certainly is generally 
regarded as the most convenient method of representing all the 
phenomena of animal life, and, as such, has passed into the best 
literature of the age. Certain it is, however, that the usual 
belief, even among the best physiologists, is that the animal 
tissue is in a state of unstable equilibrium; that constant de- 
composition is the result of this instability ; and that this decom- 
position, and this alone, creates the necessity of recomposition— 
im other words, creates the necessity of food. But, according to 
the view which I now propose, decomposition is necessary to de- 
velope the force by which organization of food or nutrition is 
effected, and by which the various purely animal functions of the 
body are carried on: that decomposition not only creates the 
necessity, but at the same time furnishes the force of recom- 
position. 
_ But it will no doubt be objected that, according to the prinei- 
ple of conservation of force, decomposition of a given amount 
of matter can only effect the recomposition of an equal amount— 
that a given quantity of matter falling a given height, can only 
raise an equal quantity an equal height: the whole force deve- 
loped by decomposition‘seems to be expended in maintaining the 
body at a given position. How then can growth and animal 
activity goon? The answer to this question is obvious enough 
when we recollect the nature of the food of animals. Animals, 
it is well known, cannot feed upon mineral matter, but only on 
food already organized, at least up to the vegetable condition. 
But when decomposition takes place, the animal matter returns 
no longer to the vegetable condition from which it was immedi- 
ately raised, but to the mineral condition. It is decomposed into 
CO? HO and urea. This last substance, though not strictly a 
mineral substance, is far below the condition of vegetable matter. 
Thus it is evident that a given quantity of matter falling down 
from the condition of animal to that of mineral matter, 7. e. from 
the 4th to the 2nd plane, would develope force sufficient to lift a 
larger quantity of matter from the vegetable to the animal condi- 
tion, i. e. from the 3rd to the 4th plane, and yet perhaps leave 
much residual foree unexpended. Thus it is possible, and not 
