y
during moonlight, in that remarkable and melancholy manner called
baying. All dogs do not do so; and, according to Houzeau, they do not
then look at the moon, but at some fixed point near the horizon. Houzeau
thinks that their imaginations are disturbed by the vague outlines of
the surrounding objects, and conjure up before them fantastic images; if
this be so, their feelings may almost be called superstitious.

Of all the faculties of the human mind, it will, I presume, be admitted
that _Reason_ stands at the summit. Only a few persons now dispute that
animals possess some power of reasoning. Animals may constantly be seen
to pause, deliberate, and resolve. It is a significant fact, that the
more the habits of any particular animal are studied by a naturalist,
the more he attributes to reason and the less to unlearned instincts. In
future chapters we shall see that some animals extremely low in the
scale apparently display a certain amount of reason. No doubt it is
often difficult to distinguish between the power of reason and that of
instinct. For instance, Dr. Hayes, in his work on "The Open Polar Sea,"
repeatedly remarks that his dogs, instead of continuing to draw the
sledges in a compact body, diverged and separated when they came to thin
ice, so that their weight might be more evenly distributed. This was
often the first warning which the travellers received that the ice was
becoming thin and dangerous. Now, did the dogs act thus from the
experience of each individual, or from the example of the older and
wiser dogs, or from an inherited habit, that is from instinct? This
instinct may possibly have arisen since the time, long ago, when dogs
were first employed by the natives in drawing their sledges; or the
Arctic wolves, the parent-stock of the Esquimau dog, may have acquired
an instinct impelling them not to attack their prey in a close pack,
when on thin ice.

We can only judge by the circumstances under which actions are
performed, whether they are due to instinct, or to reason, or to the
mere association of ideas; this latter principle, however, is
intimately connected with reason. A curious case has been given by
Professor Moebius, of a pike, separated by a plate of glass from an
adjoining aquarium stocked with fish, and who often dashed himself with
such violence against the glass in trying to catch the other fishes,
that he was sometimes completely stunned. The pike went on thus for
three months, but