at last learned caution, and ceased to do so. The
plate of glass was then removed, but the pike would not attack these
particular fishes, though he would devour others which were afterward
introduced; so strongly was the idea of a violent shock associated in
his feeble mind with the attempt on his former neighbours. If a savage
who had never seen a large plate-glass window, were to dash himself even
once against it, he would for a long time afterward associate a shock
with a window-frame; but, very differently from the pike, he would
probably reflect on the nature of the impediment, and be cautious under
analogous circumstances. Now with monkeys, as we shall presently see, a
painful or merely a disagreeable impression, from an action once
performed, is sometimes sufficient to prevent the animal from repeating
it. If we attribute this difference between the monkeys and the pike
solely to the association of ideas being so much stronger and more
persistent in the one than the other, though the pike often received
much the more severe injury, can we maintain in the case of man that a
similar difference implies the possession of a fundamentally different
mind?

Houzeau relates that, while crossing a wide and arid plain in Texas, his
two dogs suffered greatly from thirst, and that between thirty and forty
times they rushed down the hollows to search for water. These hollows
were not valleys, and there were no trees in them, or any other
difference in the vegetation, and as they were absolutely dry, there
could have been no smell of damp earth. The dogs behaved as if they knew
that a dip in the ground offered them the best chance of finding water,
and Houzeau has often witnessed the same behaviour in other animals. I
have seen, as I dare say have others, that when a small object is thrown
on the ground beyond the reach of one of the elephants in the Zoological
Gardens, he blows through his trunk on the ground beyond the object, so
that the current reflected on all sides may drive the object within his
reach. Again, a well-known ethnologist, Mr. Westropp, informs me that he
observed in Vienna a bear deliberately making with his paw a current in
some water, which was close to the bars of his cage, so as to draw a
piece of floating bread within his reach. These actions of the elephant
and bear can hardly be attributed to instinct or inherited habit, as
they would be of little use to an animal in a state of nature. Now, what
is th