115 
SYSTEM OF NATURE. 
by these circles, and have assigned a certain position to 
each group. As explanatory of this grouping I now offer 
some general observations on the principles which seem to 
have been employed more or less directly as accessories. 
Animals, on whatever plan constructed, are distinguish¬ 
able from other forms of matter by the power they possess 
of moving sponte sud from place to place. Air, earth and 
water subserve this power of locomotion. Animals are 
therefore adapted for an aerial, terrestrial, or aquatic life. 
As man, when constructing engines for moving through 
the air, on the earth or in the water, invariably adapts each 
for its respective destination by every artifice and contri¬ 
vance his ingenuity can devise, so the Divine Architect, 
with skill how infinitely superior, adapts each of his crea¬ 
tures to the element in which He wills its life shall be 
passed. So strikingly is this the case, that man is ever 
ready to adopt, as completely as he may, the forms and the 
contrivances which he finds employed in the adaptation of 
the animal frame to the requirings of diversified economy. 
Now as there are three very distinct elements—I use the 
term in its vulgar, not its scientific application — so there 
appear to be three very distinct concentric radii proceeding 
from certain points exterior to the animal kingdom, ana¬ 
logous to these three elements, and exercising a direct in¬ 
fluence over the groups of animals through which they pass. 
Let us suppose a map of the animal kingdom, in which 
the degree or grade of structure shall be expressed, as al¬ 
ready proposed, by a series of concentric rings; and let us 
imagine, exterior to the outer ring, three equidistant points, 
supposed to represent the elements, air, earth and water. 
From each of these points a line may be drawn to the com¬ 
mon centime, and these lines or radii, supposed to represent 
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