*6 Mr. Smithson’s chemical Analysis The fibrous form of the flowers of zinc, is owing to a crystalli zation of the calx while in mechanical suspension in the air, like that which takes place with camphor, when, after having been some time inflamed, it is blown out. A moment s reflection must evince, how injudicious is the common opinion, of crystallization requiring a state of solution in the matter ; since it must be evident, that while solution sub sists, as long as a quantity of fluid admitting of it is present, no crystallization can take place. The only requisite for this opera tion, is a freedom of motion in the masses which tend to unite, which allows them to yield to the impulse which propels them together, and to obey that sort of polarity which occasions them to present to each other the parts adapted to mutual union. No state so completely affords these conditions as that of me chanical suspension in a fluid whose density is so great, rela tively to their size, as to oppose such resistance to their descent in it as to occasion their mutual attraction to become a power superior to their force of gravitation. It is in these circumstances that the atoms of matters find themselves, when, on the sepa ration from them of the portion of fluid by which they were dissolved, they are abandoned in a disengaged state in the bosom of a solution; and hence it is in saturated solutions sustaining evaporation, or equivalent cooling, and free from any perturbing motion, that regular crystallization is usually effected. But those who are familiar with chemical operations, know the sort of agglutination which happens between the particles of subsided very fine precipitates; occasioning them, on a second diffusion through the fluid, to settle again much more quickly than before, and which is certainly a crystallization, but under circumstances very unfavourable to its perfect performance.