210 
SPHERICAL ELEMENTS OF CRYSTALS. 
sis does not re- 
quire physical 
atoms, but 
only spheres 
of energy. 
The metals, 
whicli are pro- 
bably the most 
simple bodies, 
favour this 
doctrine. 
tide, accords so well with the most recent views of binary 
combination in chemistry, that there can be no necessity, on 
the present occasion, to enter into any defence of that doctrine, 
as applied to this subject. And though the existence of ulti- 
mate physical atoms, absolutely indivisible, may require de- 
monstration, their existence is by no means necessary to any 
hypothesis here advanced, which requires merely mathemati- 
cal points endued with powers of attraction and repulsion 
equally on all sides, so that their extent is virtually spheri- 
cal j for, from the union of such particles the same solids 
will result as from the combination of spheres impenetrably 
hard. 
There remains one observation with regard to the spherical 
form of elementary particles, whether actual or virtual, that 
must be regarded as favourable to the foregoing hypothesis, 
namely, that many of those substances which we have most 
reason to think simple bodies, as among the class of metals, 
exhibit this further evidence of their simple nature, that they 
crystallize in the octohedral form, as they would do if their 
particles were spherical. 
But it must, on the contrary, be acknowledged, that w’e can, 
at present, assign no reason why the same appearance of sim- 
plicity should take place in fluor spar, which is presumed to 
contain at least two elements j and it is evident, that any at- 
tempts to trace a general correspondence between the crystallo- 
graphical and supposed chemical elements of bodies must, in 
the present state of these sciences, be premature. 
. Note. 
Theory of M. A theory has lately been advanced* by M. Prechtl, whick 
Preclitl Lf the a(te,-nnts to account for various crystalline forms from the dif- 
conijiressiiM i •/ 
ofkdftspbeju;. ferent degrees of compression that soft spheres may be sup- 
nosed to undergo in assuming the solid state. It is supposed, 
* .Journal des Mines. No. !(•#. 
that 
