442 
THE GEOLOGIST. 
there must be a motion of the external hardened crust different from 
that of the internal fluid mass, and this motion must go on, if the 
present views of mathematicians, astronomers, and internal-heat 
geologists are right, without any friction. Now, if the earth's crust 
is the effect of a cooling-down process from a molten condition, there 
must be a gradual hardening still going on; and with such a gradual 
hardening, there must be a portion intermediate between the solid 
crust and the fluid core, which must be in every possible degree 
of viscosity from next to hard to next to fluid ; and if there be an}'- 
difference of motion between the external crust and the internal 
core, such an intermediate viscous portion must be a source of much 
friction, it being absolutely in the very zone where friction would be 
manifested. There is no manner of doubt whatever that the internal- 
heat doctrine was invented to account for the supposed former higher 
temperature of our planet, — a point also not yet proven. Still, we 
are not adverse to the idea of former differences of temperature ; but 
will they be found, when facts and experience have determined more 
exactly the grander truths, repeatedly variable, or permanently in one 
direction or the other ? 
One subject has never, as far as we know, been contemplated 
by either geologists or astronomers. AYe are taught at school to 
believe, and it is generally asserted in society, that the orbits of our 
earth and the other planets are nearly circular, or at most but 
slightly elliptical ; and these ellipses are supposed to work round 
periodically, and thus to right themselves. We are taught, too, 
to believe in the fixity and permanence of the planetary and sidereal 
systems, and that the great Creator has laid the foundations of the 
world so sure that they can never be moved. Now, on the c(mtrary, 
we sincerely believe that all creation, throughout all space, is in 
as active a state of change as the world we inhabit, upon which no 
day brings forth its similitude, and no one night is like another. If 
the sun be a burning body, whatever it consumes must be dissipated 
as vapour, or solidified as incombustible matter upon its surface. If 
the sun be dissipating its mass, it is lessening in bulk, and its attrac- 
tion upon the earth must be lessened. If the sun be adding any 
residue of combustion to its mass, then the attraction of the sun 
upon the earth increases. If the attraction diminished, the earth 
would recede from the sun ; if the attraction increased, the earth 
would be drawn nearer towards it, unless the velocity of the earth in 
its orbit increased or diminished, so as to make a compensation. 
i 
