THE UNITY OF THE DEITY 
251 
in substance, shape, and office: digestion, nutrition, cir 
culation, secretion, go on, in a similar manner, in all. The 
great circulating fluid is the same; for, I think, no differ 
ence has been discovered in the properties of blood, from 
whatever animal it be drawn. The experiment of transfu 
sion proves, that the blood of one animal will serve for an¬ 
other. The skeletons also of the larger terrestrial animals, 
show particular varieties, but still under a great general 
affinity. The resemblance is somewhat less, yet sufficiently 
evident, between quadrupeds and birds. They are all alike 
in five respects, for one in which they differ. 
In Jish, which belong to another department, as it were, 
of nature, the points of comparison become fewer. But we 
never lose sight of our analogy, e. g. we still meet with a 
stomach, a liver, a spine; with bile and blood; with 
teeth; with eyes,—(which eyes are only slightly varied from 
our own, and which variation, in truth, demonstrates, not 
an interruption, but a» continuance of the same exquisite 
plan; for it is the adaptation of the organ to the element, 
viz. to the different refraction of light passing into the eye 
out of a denser medium.) The provinces, also, themselves 
of water and earth, are connected by the species of ani¬ 
mals which inhabit both; and also by a large tribe of aquat¬ 
ic animals, which closely resemble the terrestrial in their 
internal structure; I mean the cetaceous tribe, which have 
hot blood, respiring lungs, bowels, and other essential 
parts, like those of land animals. This similitude, surely, 
bespeaks the same creation and the same Creator. 
Insects and shell-fish appear to me to differ from other 
classes of animals the most widely of any. Yet even here, 
beside many points of particular resemblance, there exists 
a general relation of a peculiar kind. It is the relation of 
inversion; the law of contrariety: namely, that whereas, 
in other animals, the bones, to which the muscles are at¬ 
tached, lie vnthin the body; in insects and shell-fish they 
lie on the outside of it. The shell of a lobster performs to 
the animal the office of a bone, by furnishing to the ten¬ 
dons that fixed basis or immovable fulcrum, without which, 
mechanically, they could not act. The crust of an insect 
is its shell, and answers the like purpose. The shell also 
of an oyster stands in the place of a bone; the bases of the 
muscles being fixed to it, in the same manner as, in other 
animals, they are fixed to the bones. All which (under 
wonderful varieties, indeed, and adaptations of form) con¬ 
fesses an imitation, a remembrance, a carrying on, of the 
*ame plan 
