Aristotle's essay on the horse, and
continued the subject further, dissecting the animal in minutest detail
and illustrating his discoveries with painstaking drawings. His work is
so complete and exhaustive that nobody nowadays has time to more than
read the title-page. Leonardo's bent was natural science, and his first
attempts at drawing were done to illustrate his books. Art was
beautiful, of course--it brought in an income, made friends and brought
him close to people who saw nothing unless you made a picture of it. He
made pictures for recreation and to amuse folks, and his threat to put
the peeping Prior into the "Last Supper," posed as Judas, revealed his
contempt for the person to whom a picture was just a picture. The marvel
to Leonardo was the mind that could imagine, the hand that could
execute, and the soul that could see.

And the curious part is that Leonardo lives for us through his play and
not through his serious work. His science has been superseded, but his
art is immortal.

This expectant mental attitude, this attitude of worship, belongs to all
great scientists. The man divines the thing first and then looks for it,
just as the Herschels knew where the star ought to be and then patiently
waited for it. The Bishop of London said that if Darwin had spent
one-half as much time in reading his Bible as in studying earthworms, he
would have really benefited the world, and saved his soul alive. To
Walt Whitman, a hair on the back of his hand was just as curious and
wonderful as the stars in the sky, or God's revelation to man through a
printed book.

Aristotle loved animals as a boy loves them--his house was a regular
menagerie of pets, and into this world of life Alexander was very early
introduced. We hear of young Alexander breaking the wild horse,
Bucephalus, and beyond a doubt Aristotle was seated on the top rail of
the paddock when he threw the lariat.

Aristotle and his pupil had the first circus of which we know, and they
also inaugurated the first Zoological Garden mentioned in history,
barring Noah, of course.

So much was Alexander bound up in this menagerie, and in his old teacher
as well, that in after-life, in all of his travels, he was continually
sending back to Aristotle specimens of every sort of bird, beast and
fish to be found in the countries through which he traveled.

When Philip was laid low by the assassin's thrust, it was Aristotle who
backed up Alexander, aged twenty--but