body, while the soluble portions are taken up into the blood. The
blood is contained in a vast system of pipes, spreading through the
whole body, connected with a force pump,--the heart,--which, by its
position and by the contractions of its valves, keeps the blood
constantly circulating in one direction, never allowing it to rest; and
then, by means of this circulation of the blood, laden as it is with
the products of digestion, the skin, the flesh, the hair, and every
other part of the body, draws from it that which it wants, and every
one of these organs derives those materials which are necessary to
enable it to do its work.

The action of each of these organs, the performance of each of these
various duties, involve in their operation a continual absorption of
the matters necessary for their support, from the blood, and a constant
formation of waste products, which are returned to the blood, and
conveyed by it to the lungs and the kidneys, which are organs that have
allotted to them the office of extracting, separating, and getting rid
of these waste products; and thus the general nourishment, labour, and
repair of the whole machine is kept up with order and 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