d regularity. But
not only is it a machine which feeds and appropriates to its own
support the nourishment necessary to its existence--it is an engine for
locomotive purposes. The Horse desires to go from one place to another;
and to enable it to do this, it has those strong contractile bundles of
muscles attached to the bones of its limbs, which are put in motion by
means of a sort of telegraphic apparatus formed by the brain and the
great spinal cord running through the spine or backbone; and to this
spinal cord are attached a number of fibres termed nerves, which proceed
to all parts of the structure. By means of these the eyes, nose,
tongue, and skin--all the organs of perception--transmit impressions
or sensations to the brain, which acts as a sort of great central
telegraph-office, receiving impressions and sending messages to all
parts of the body, and putting in motion the muscles necessary to
accomplish any movement that may be desired. So that you have here an
extremely complex and beautifully-proportioned machine, with all its
parts working harmoniously together towards one common object--the
preservation of the life of the animal.

Now, note this: the Horse makes up its waste by feeding, and its food
is grass or oats, or perhaps other vegetable products; therefore, in the
long run, the source of all this complex machinery lies in the vegetable
kingdom. But where does the grass, or the oat, or any other plant,
obtain this nourishing food-producing material? At first it is a little
seed, which soon begins to draw into itself from the earth and the
surrounding air matters which in themselves contain no vital properties
whatever; it absorbs into its own substance water, an inorganic body;
it draws into its substance carbonic acid, an inorganic matter; and
ammonia, another inorganic matter, found in the air; and then, by some
wonderful chemical process, the details of which chemists do not yet
understand, though they are near foreshadowing them, it combines
them into one substance, which is known to us as 'Protein,' a complex
compound of carbon, hydrogen, oxygen, and nitrogen, which alone
possesses the property of manifesting vitality and of permanently
supporting animal life. So that, you see, the waste products of the
animal economy, the effete materials which are continually being thrown
off by all living beings, in the form of organic matters, are constantly
replaced by supplies of the necessary repairing and