on Basalt, &c. 
2 91 
It has been most justly remarked by Mr. Smithson, that 
solution, far from being necessary to crystallization, effectually 
prevents its commencement; for, while solution subsists, crys- 
tallization cannot take place. It may remain a question, whether 
previous solution be essential, as a preparatory means of ob- 
taining, by subsequent evaporation, or cooling, the small parts 
of bodies disengaged, so that they may unite to form regular 
crystals. If by solution be only meant, that simple action of 
heat, or water, which merely counteracts the force of aggrega- 
tion, and relieves the molecules from their bond of union with 
each other, it certainly is a requisite; but if by solution be 
meant, that action of affinities by which not only the force of 
aggregation is overcome, but the combinations which constitute 
the molecules are destroyed, it obviously is not only unnecessary, 
but prejudicial to crystallization ; as a new set of molecules 
must be formed, by a new combination of the elementary 
particles, before the formation of regular bodies can commence. 
The suspension of the molecules ready to crystallize, may be 
correctly said to be merely mechanical. Though the mechanical 
action of trituration can never be expected to resolve even the 
most easily divisible body into its molecules, because the frac- 
tures will be at least as frequently across the natural joints as 
in their direction, yet, even by this rude method, some perfect 
molecules may be disengaged ; for we find, that water passing 
over large surfaces of siliceous sand, finds some molecules of 
silex in the state proper for aggregation, and even for crystalli- 
zation. Mechanical suspension in a fluid medium, of such 
density that the crystalline polarity may be enabled to counteract 
the power of gravity, is with justice considered by Mr. Smithson 
