Notices respecting New Books. 301 
primitive form, which shcw by their relative position, and mu- 
tual connexion, the gradual steps by which one form passes into 
another.” 
Borax, crystals of sulphate of copper, sulphate of magnesia, 
submitted to cautious solution, also yielded distinct crystalline 
forms. Crystals of carbonate of lime, carbonate of barytes, a 
erystal of quartz, and a polished carnelian, submitted cautiously 
to the action of their proper solvents, gave similar indications, 
but rendered less perfect, in some instances, by extricated gas 
making paths for its escape along the surface of the crystal, and 
there preventing the regular action of the acid. Bismuth, nickel, 
antimony, and some other metals gave evidence also of regular 
erystallization.—The author, after detailing these experiments, 
proceeds to inquire ‘* whether this new method of analysis may 
not be calculated to throw some light upon crystalline arrange- 
ments in general?” He then describes particularly the crystalline 
forms brought to view on the surface of the piece of alum, with 
& view to a proper theory which may agree with all the results. 
*¢ It is evident,”’ he remarks, “ that no general theory of crys- 
tallization can be applied tothe cases under contemplation, which 
is not founded upon such a disposition of constituent particles as 
may furnish all the modifications of form before described, by the 
mere abstraction of certain individuals from a congeries, without 
altering the original relative position of those which remain. 
That is to say, supposing we adopt the hypothesis of the spheri- 
eal form’of the molecules, it will not be sufficient that a cube 
may be constructed by the superposition of four balls upon the 
top of four other balls *, and an octohedron by placing four 
spheres in a square, with two others in the interstices between 
them (in which two combinations it is evident that the position 
of no three particles is alike); but the disposition of the cube 
must include that of the octohedron, and this latter must be 
obtainable by the equal abstraction of certain members of the 
former, without interfering with the quiescent state of the re- 
mainder.” 
- He then assumes, for inquiry, the sphere as the form of the 
primitive particles, and proceeds to construct figures to illustrate 
their relative position, and to prove whether by the abstraction 
of certain rows or quantities of spheres from the mass, without 
disturbing those that are left, the mass or any portion of it can 
be made to exhibit the required forms. He makes a base of 36 
halls, on these other balls to the number of 25 are placed in a 
| plane occupying the interstices formed on the surface of the 36. 
_* See the construction of the cube as proposed by W, II. Wollaston, 
M.D. Sec, R.S. Phil. Trans. 1812. 
On 
