ond, they become too shrill for our ears. It
is thought that the world of sound with the insects begins where ours
leaves off. The drums and tubes of insects' ears are very minute. What
would to us be a continuous sound is to them a series of separate blows.
We begin to hear blows as continuous sounds when they amount to about
thirty a second. The house-fly has about four thousand eye-lenses; the
cabbage butterfly, and the dragon-fly, about seventeen thousand; and
some species of beetles have twenty-five thousand. We cannot begin to
think in what an agitated world the insect lives, thrilling and
vibrating to a degree that would drive us insane. If we possessed the
same microscopic gifts, how would the aspect of the world be changed! We
might see a puff of smoke as a flock of small blue butterflies, or hear
the hum of a mosquito as the blast of a trumpet. On the other hand, so
much that disturbs us must escape the insects, because their senses are
too fine to take it in. Doubtless they do not hear the thunder or feel
the earthquake.

The insects are much more sensitive to heat and cold than we are, and
for reasons. The number of waves in the ether that gives us the
sensation of heat is three or four million millions a second. The number
of tremors required to produce red light is estimated at four hundred
and seventy-four million millions a second, and for the production of
violet light, six hundred and ninety-nine million millions a second. No
doubt the insects react to all these different degrees of vibration.
Those marvelous instruments called antennae seem to put them in touch
with a world of which we are quite oblivious.

X

To how many things our lives have been compared!--to a voyage, with its
storms and adverse currents and safe haven at last; to a day with its
morning, noon, and night; to the seasons with their spring, summer,
autumn, and winter; to a game, a school, a battle.

In one of his addresses to workingmen Huxley compared life to a game of
chess. We must learn the names and the values and the moves of each
piece, and all the rules of the game if we hope to play it successfully.
The chessboard is the world, the pieces are the phenomena of the
universe, the rules of the game are what we call the laws of nature.
But it may be questioned if the comparison is a happy one. Life is not a
game in this sense, a diversion, an aside, or a contest for victory over
an opponent, except in isolated episodes now