210° W. A. Norton on Molecular Physics. 
the circumstances that determine the crystallization. The gene 
ral nature of the modifications consists in a spheroidal form im- 
parted to the molecular atmospheres, and the consequent devel- 
opment of certain axes of attraction; that is, of diameters of 
least or greatest length, in the direction of which the attraction 
has, at a given distance, a maximum or minimum value, and the 
limit of stable equilibrium (Oa, fig. 1) a minimum or maximum 
faces of these figures, e have then first to consider the pro 
cess of crystallization, as it may occur in a single plane. 
The result of every such process is arrangement of the 
unite with those already crystallized, three different general 
modes of arrangement may occur; the new 
up positions opposite those of the first line, or opposite the mid- 
. . re: a rectangle, or a rhombus. The two molecular axeS — 
_wul be coincident 4 sides of the minute pane lar fig: 
ures that make up the larger rectangle, and with the diagon@* 
_ of each minute rhombus. The condition ; 
ied 
a a Sa en ee Te ee 
ion essential.to the form®™ 
