BY MOLECULAR COALESCENCE. 53 
structure of the larger globular calculi as noticed at page 
30; where, as well as in other parts, it has been observed 
that the globular carbonate of lime, when in small quan- 
tities, exists in the form of bright, homogeneous spherules, 
looking very much like globules of oil or bubbles of air, 
but that, after beimg incorporated into large spherical 
masses, these forms entirely vanish, and are replaced by 
concentric laminze and fine lines radiating from the centre 
to the circumference. The formation of the laminz has 
been explained; it now remains to consider that of the 
radiating lines. Now, as the explanation of all the ap- 
pearances presented by these calculi has so far been 
shown to be the result of attraction, it is only a fair in- 
ference that these lines also are due to the effect of the 
same force. But in the last article attraction has been 
shown to be the direct antagonist of rectilinear molecular 
arrangement; therefore an apparent incongruity arises, 
which I will now explain. In perfect spheres, constructed 
on the principle of universal attraction, all the molecules, 
being attracted in directions parallel with their circumfer- 
ence by equal and opposite forces, are as if not attracted 
at all by any force acting upon them laterally ; and there- 
fore the sensible effect of gravity upon these molecules 
can only be exerted in one direction, that is to say, 
it can only act im straight lines extending from the 
circumference to the centre. Hence, such being the 
action of gravity in spheres, it is clear that so far as 
the rectilinear arrangement of their molecules is con- 
cerned, the effect of gravity, and that of impulsion 
upon them is the same. But attraction thus operating 
upon these molecules does not produce perfect crystals, 
nor does impulsion acting on similar molecules produce 
lines like these. These lines, though presenting an im- 
