50 PHILOSOPHY OF ZOOLOGY. 
When we attentively consider the present condition of 
the inorganic kingdom, it will appear obvious, that the con- 
tinuance of its existence and arrangement does not depend 
on the presence of organized bemgs. Independent of its 
vegetable covering, of the animals by which it is peopled, 
and of man himself, this globe could still revolve in its or- 
bit, and act its part in the solar system, though naked, 
silent and lifeless, Changes would, indeed, take place on 
its surface, in consequence of the laws of chemistry and 
mechanics, and independent of the aid of living bodies. 
The prominent parts would be worn down; the hollows 
would be filled up ; and its outline would assume an inclina- 
tion every where at right angles with the direction of gra- 
vity. These changes have, in part, been accomplished ; 
and have impressed on the different strata the peculiar cha- 
racters of their structure and superposition. 
The organized kingdom, on the other hand, could not ex- 
ist alone. The beings of which it is composed may be con- 
sidered as the parasites of this planet, and depend on its 
present movements for the exercise of their functions. Were 
the earth to approach nearer the sun, or recede to a greater 
distance, organized existence would be destroyed, by the 
mere change of temperature. 
The presence of the inorganic kingdom, is necessary to 
the existence both of plants and animals, as furnishing them 
with the elements of their composition, and a place of resi- 
dence. Plants may be considered as more immediately de- 
pendent on the imorganic kingdom than animals. Their 
attachment to the soil is more obvicus; and the changes 
which take place in its condition, exert a more direct influ- 
ence over them. The lichens cover the exposed surface of 
the rock ; and, by the retention of moisture, accelerate its 
decomposition. The mosses next establish themselves in 
the hollows and crevices ; and, by degrees, prepare a soil for 
the stamenifcrous vegetables. These last attempt to esta- 
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