BY MOLECULAR COALESCENCE. ad 
® 
which has been given of the formation of these bodies, 
and nothing can be more plausible and apparently correct, 
if only the foundation upon which it rests is solid. The 
question on the other side is, can any other explanation 
of the same class of facts, equally plausible, be given. To 
this question it may be replied, that no other explanation 
which suits so completely all the circumstances of the 
case can be advanced, without removing entirely the foun- 
dation upon which this one is built. The following ex- 
planation of the manner in which these calculi are formed, 
unconnected altogether with the hypothesis of cell-growth, 
and in accordance with facts as shown by experiment, is 
deduced from the comparison of the results of the artificial 
process for making calculi with those of the natural pro- 
cess. As there can be no doubt but that the ure of the 
horse, when recently secreted, contains in solution som® 
compound of lime, albuminous matter, and some salt of 
urea, easy of decomposition, and when decomposed, fur- 
nishing carbonate of ammonia; it is obvious that, as soon 
as this decomposition of the urea or its salts commences, 
all the conditions necessary for the formation of the 
globular carbonate of lime specified in the artificial pro- 
cess are brought into existence. The carbonic acid set 
free by the decomposition of the carbonate of ammonia 
would combine with the lime, displacing the acid before 
combined with it, to form a carbonate of lime, which, 
meeting in its nascent state with the albumen, would form 
with it the globular or coalescing compound in question, 
the particles of which, being suspended in a fluid medium, 
holding animal matter in solution, would coalesce to form 
globules of various sizes and degrees of perfectness, accord- 
ingly as all the other conditions prescribed in the artificial 
process were more or less favorable for the process of 
