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use, we should be as perfectly assured that it proceeded from the hand, and thought, and skill of a workman, as if we visited a museum of the arts, and saw collected there twenty different kinds of machines for drawing water, or a thousand different kinds for other purposes. Of this point, each machine is a proof, independently of all the rest. So it is with the evidences of a Divine agency. The proof is not a conclusion which lies at the end of a chain of reasoning, of which chain each instance of contrivance is only a link, and of which, if one link fail, the whole falls but it is an argument separately supplied by every separate example. An error in stating an example, affects only that example. The argument is cumulative, in the fullest sense of that term. The

The eye proves it without the ear; the ear without the eye. The proof in each example is complete; for when the design of the part, and the conduciveness of its structure to that design is shown, the mind may set itself at rest; no future consideration can detract any thing from the force of the example.

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It is not that every part of an animal or ve-
getable has not proceeded from a contriving
mind; or that every part is not constructed
with a view to its proper end and purpose,
according to the laws belonging to, and go-
verning the substance or the action made use
of in that part; or that each part is not so
constructed as to effectuate its
it operates according to these laws; but it is
because these laws themselves are not in all
cases equally understood; or, what amounts
to nearly the same thing, are not equally ex-
emplified in more simple processes, and more
simple machines; that we lay down the di:
stinction, here proposed, between the mecha-
nical parts and other parts of animals and
vegetables.

For instance: the principle of muscular níotion, viz. upon what cause the swelling of the belly of the muscle, and consequent contraction of its tendons, either by an act of the will, or by involuntary irritation, depends, is wholly unknown to us. The substance

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employed, whether it be Auid, gaseous,
elastic, electrical, or none of these, or now
thing resembling these, is also unknown
to us: of course, the laws belonging to
that substance, and which regulate its ac-
tion, are unknown to us. We see nothing
similar to this contraction in any machine
which we can make, or any process which we
can execute. So far (it is confessed) we are
in ignorance, but no further. This power
and principle, from whatever cause it pro-
ceeds, being assumed, the collocation of the
fibres to receive the principle, the disposition
of the muscles for the use and application of
the power, is mechanical; and is as intelligi-
ble as the adjustment of the wires and strings
by which a puppet is moved. We
fore, as far as respects the subject before us,
what is not mechanical in the animal frame,
and what is. The nervous influence (for we
are often obliged to give names to things
which we know little about)—I say the nera
vous influence, by which the belly, or mid-
dle, of the muscle is swelled, is not mechania
cal. The utility of the effect we perceive;
the means, or the preparation of means, by
which it is produced, we do not. But obscu-
rity as to the origin of muscular motion
brings no doubtfulness into our observations,

We see,

see, there

upon the sequel of the process. Which observations relate, 1st, to the constitution of the muscle ; in consequence of which constitution, the swelling of the belly or middle part is necessarily and mechanically followed by a contraction of the tendons : 2dly, to the number and variety of the muscles and the corresponding number and variety of useful powers which they supply to the animal ; which is astonishingly great: 3dly, to the judicious (if we may be permitted to use that term, in speaking of the author, or of the works of nature), to the wise and well-contrived disposition of each muscle for its specific purpose ; for moving the joint this way; and that

way,

and the other way ; for pulling and drawing the part, to which it is attached in a determinate and particular direction; which is a mechanical operation, exemplified in a multitude of instances. To mention only one: The tendon of the trochlear muscle of the eye, to the end that it may draw in the line required, is passed through a cartilaginous ring, at which it is reverted, exactly in the same manner as a rope in a ship is carried over a block or round a stay, in order to make it pull in the direction which is wanted. All this, as we have said, is mechanical; and is as accessible to inspection, as

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capable of being ascertained, as the miechanism of the automaton in the Strand. Supe pose the automaton to be put in motion by a magnet (which is probable), it will supply us with a comparison very apt for our present purpose.

Of the magnetic effluvium, we know perhaps as little as we do of the nervous fuid. But, magnetic attraction being assumed (it signifies nothing from what cause it proceeds), we can trace, or there can be pointed out to us, with perfect clearness and certainty, the mechanism, viz. the steel bars, the wheels, the joints, the wires, by which the motion so much admired is communicated to the fingers of the image: and to make any obscurity, or difficulty, or controversy in the doctrine of magnetism, an objection to our knowledge or our certainty, concerning the contrivance, or the marks of contrivance, displayed in the automaton, would be exactly the same thing, as it is to make our ignorance (which we acknowledge) of the cause of nervous agency, or even of the substance and structure of the nerves themselves, a ground of question or suspicion as to the reasoning which we institute concerning the mechanical part of our frame. That an animal is a machine, is a proposition neither correctly true nor wholly false. The distinction which we have been discussing

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