Let us take some simple case in illustration. In quiet water we have very finely divided matter suspended, and matter in a state of solution. The first is slowly precipitated, and in process of time consolidates into a hard mass at the bottom, presenting no particular character, unless it has been placed in some peculiar physical conditions; when, as in nature, we have a regular bedding which is intersected by lines of lamination or of cleavage, which we are, from experiment, enabled to refer to the influence of current electricity. The second--the matter in solution--is also slowly deposited; but it is accumulated upon nuclei which possess some peculiar disposing powers, and every particle is united by some particular face, and an angular figure of the most perfect character results. Many pleasing experiments would appear to show that electricity has much to do in the process of crystallization; but it is evident that it must be under some peculiarly modified conditions that this power is exerted, if, indeed, it has any direct action. The same substances always crystallize in the same forms, unless the conditions of the crystallizing body are altered. It has been supposed that each particle of a crystalline mass has certain points or poles which possess definite properties, and that cohesion takes place only along lines which have some relation to the attracting or repelling powers of these poles. We shall have, eventually, to consider results which appear to prove that magnetism is universal in its influence, and that this polarity of the particles of matter may be referred to it. Be the cause of crystallisation what it may, it presents to us in appearance a near approach in inorganic nature to some of the peculiar conditions of growth in the organised creation. In one, we have the gradual production of parts and the formation of members due to peculiar powers of assimilation, each individual preserving all its distinguishing features; and in the other, we have a regular order of cohesion occurring under the influence of a power which draws like to like, and arranges the whole into a form of beauty. This appears to be the proper place for correcting an error too prevalent, relative to the formation of crystals, the development of cells, and the yet more fatal falsehood of referring the great phenomena of Life to any of the physical forces with which we are acquainted. THE CRYSTAL _forms_, by the accretion of particle to particle, along lines determined by some yet unknown power. There is no change in the character of any particle--like coheres to like; the first atom and the last of the series being identical in character.