, however, he was not and could not be. He often complains that his
head is too busy for his body. In the enforced solitude of Arcetri he
was composing those dialogues on motion which are now reckoned his
greatest and most solid achievement. In these the true laws of motion
are set forth for the first time (see page 167). One more astronomical
discovery also he was to make--that of the moon's libration.

And then there came one more crushing blow. His eyes became inflamed and
painful--the sight of one of them failed, the other soon went; he
became totally blind. But this, being a heaven-sent infliction, he could
bear with resignation, though it must have been keenly painful to a
solitary man of his activity. "Alas!" says he, in one of his letters,
"your dear friend and servant is totally blind. Henceforth this heaven,
this universe, which by wonderful observations I had enlarged a hundred
and a thousand times beyond the conception of former ages, is shrunk for
me into the narrow space which I myself fill in it. So it pleases God;
it shall therefore please me also."

He was now allowed an amanuensis, and the help of his pupils Torricelli,
Castelli, and Viviani, all devotedly attached to him, and Torricelli
very famous after him. Visitors also were permitted, after approval by a
Jesuit supervisor; and under these circumstances many visited him, among
them a man as immortal as himself--John Milton, then only twenty-nine,
travelling in Italy. Surely a pathetic incident, this meeting of these
two great men--the one already blind, the other destined to become so.
No wonder that, as in his old age he dictated his masterpiece, the
thoughts of the English poet should run on the blind sage of Tuscany,
and the reminiscence of their conversation should lend colour to the
poem.

Well, it were tedious to follow the petty annoyances and troubles to
which Galileo was still subject--how his own son was set to see that no
unauthorized procedure took place, and that no heretic visitors were
admitted; how it was impossible to get his new book printed till long
afterwards; and how one form of illness after another took possession of
him. The merciful end came at last, and at the age of seventy-eight he
was released from the Inquisition.

They wanted to deny him burial--they did deny him a monument; they
threatened to cart his bones away from Florence if his friends attempted
one. And so they hoped that he and his work might be forgotten.