hide things, plants many of our oak and chestnut trees,
but who dares say that he does this on purpose, any more than that the
insects cross-fertilize the flowers on purpose? Sheep do not take
thought of the wool upon their backs that is to protect them from the
cold of winter, nor does the fox of his fur. In the tropics sheep
cease to grow wool in three or four years.

All the lower animals, so far as I know, swim the first time they find
themselves in the water. They do not have to be taught: it is a matter
of instinct. It is what we should expect from our knowledge of their
lives. Not so with man; he must learn to swim as he learns so many
other things. The stimulus of the water does not at once set in motion
his legs and arms in the right way, as it does the animal's legs; his
powers of reason and reflection paralyze him--his brain carries him
down. Not until he has learned to resign himself to the water as the
animal does, and to go on all fours, can he swim. As soon as the boy
ceases to struggle against his tendency to sink, assumes the
horizontal position, and strikes out as the animal does, with but one
thought, and that to apply his powers of locomotion to the medium
about him, he swims as a matter of course. It is said that children
have sometimes been known to swim when thrown into the water. Their
animal instincts were not thwarted by their powers of reflection.
Doubtless this never happened to a grown person. Moreover, is it not
probable that the specific gravity of the hairless human body is
greater than that of the hair-covered animal, and that it sinks, while
that of the cat or dog floats? This, with the erect position of man,
makes swimming with him an art that must be acquired.

There is no better illustration of the action of instinct as opposed
to conscious intelligence than is afforded by the parasitic
birds,--the cuckoo in Europe and the cowbird in this country,--birds
that lay their eggs in the nests of other birds. Darwin speculates as
to how this instinct came about, but whatever may have been its
genesis, it is now a fixed habit among these birds. Moreover, the
instinct of the blind young alien, a day or two after it is hatched,
to throw or crowd its foster-brothers out of the nest is a strange and
anomalous act, and is as untaught and unreasoned as anything in
vegetable life. But when our yellow warbler, finding this strange egg
of the cowbird in her nest, proceeds to bury it by putting anot