122 
COMPARATIVE ANATOM!. 
had not appeared subservient to the purpose of motion as 
well as of defence. What distinguishes the skull from every 
other cavity is, that the bony covering completely surrounds 
its contents, and is calculated, not for motion, but solely for 
defence. Those hollows, likewise, and inequalities, which 
we observe in the inside of the skull, and which exactly fit 
the folds of the brain, answer the important design of keep¬ 
ing the substance of the brain steady, and of guarding it 
against concussions 
CHAPTER XII. 
COMPARATIVE ANATOMY. 
Whenever we find a general plan pursued, yet with 
such variations in it as are, in each case required by the 
particular exigency of the subject to which it is applied, we 
possess, in such plan and such adaptation, the strongest evi¬ 
dence that can be afforded of intelligence and design; an 
evidence which most completely excludes every other 
hypothesis. If the general plan proceeded from any fixed 
necessity in the nature of things, how could it accommodate 
itself to the various wants and uses which it had to serve 
under different circumstances, and on different occasions? 
Arkwright’s mill was invented for the spinning of cotton. 
We see it employed for the spinning of wool, flax, and 
hemp, with such modifications of the original principle, 
such variety in the same plan, as the texture of those dif¬ 
ferent materials rendered necessary. Of the machine’s 
being put together with design, if it were possible to doubt, 
whilst we saw it only under one mode, and in one form; 
when we came to observe it in its different applications, 
with such changes of structure, such additions, and supple¬ 
ments, as the special and particular use in each case de¬ 
manded, we could not refuse any longer our assent to the 
proposition, “that intelligence, properly and strictly so 
called, (including under that name, foresight, consideration, 
reference to utility,) had been employed, as well in the 
primitive plan, as in the several changes and accommoda¬ 
tions which it is made to undergo.” 
Very much of this reasoning is applicable to what has 
been called Comparative Anatomy. In their general econ¬ 
omy, in the outlines of the plan, in the construction as well 
as offices of their principal parts, there exists between all 
