235 
Dr, Hutton ingeniously laboured to establish his hypothesis of 
the succession of worlds by a system of revolutions, occurring at 
regular periods, each successive period of existence being, according 
to our measurement of time, of indefinite duration; leaving us 
no vestige of a beginning, — nor prospect of an end. Agreeable to 
this hypothesis, the Doctor imagined that coal is formed by the 
slow deposition of oily and bituminous matters at the bottom of 
the sea. These bituminous and oily matters he supposes to have 
originated in the dissolution of the various animal and vegetable 
bodies, which are continually perishing on the surface of the earth, 
and in the waters of the ocean. The fuliginous matter which is 
separated during the combustion of various bodies on the surface 
of the earth, he supposed to be washed otf the surfaces on which 
it falls, by the rain, and, being thus made to flow into the rivers, is 
carried by them into the sea ; where it also adds, by its deposition, 
to the mass which is accumulating at its bottom. Another source 
from which he supposes this matter to be derived, is the moss -water, 
or the water which drains from peat-mosses. This moss-water, the 
Doctor says, leaves, upon evaporation, a bituminous substance, 
which very much resembles fossil coal ; and, as the continued action 
of the sun and atmosphere upon this oily substance tends, by in- 
spissation, to make it more and more dense or bituminous, he, 
therefore, saw no difficulty in supposing a continual separation of 
this bituminous matter, or inspissated oil, from the water ; and a 
precipitation of it to the bottom of the sea, along with the subtle 
earthy particles which the water also contains. These he supposed 
to subside together in an uniform manner, producing a stratified 
mass, which, becoming covered by an immense weight of super- 
incumbent earth, must have been thereby exceedingly compressed 
and condensed, and finally consolidated, by the powerful influence 
of subterranean heat. 
Waving, as foreign to the immediate object of our inquiry, any 
