of the best eighteenth-century books on the calculus,
and had a special dispensation from the Pope to teach mathematics
at Bologna. We were therefore very glad to accept an invitation
from Lady Hamilton to spend an evening with a few of her friends.
Her rooms were fairly filled with books, the legacy of one of whom
it was said that "scarcely a thought has come down to us through
the ages which he has not mastered and made his own."

The few guests were mostly university people and philosophers.
The most interesting of them was Professor Blackie, the Grecian
scholar, who was the liveliest little man of sixty I ever saw;
amusing us by singing German songs, and dancing about the room like
a sprightly child among its playmates. I talked with Miss Hamilton
about Mill, whose "Examination of Sir William Hamilton's Philosophy"
was still fresh in men's minds. Of course she did not believe in this
book, and said that Mill could not understand her father's philosophy.
With all her intellect, she was a fine healthy-looking young lady,
and it was a sad surprise, a few years later, to hear of her death.
Madame Sophie Kovalevsky afterward appeared on the stage as the
first female mathematician of our time, but it may be feared that
the woman philosopher died with Miss Hamilton.

A large party of English astronomers were going to Algeria to observe
the eclipse. The government had fitted up a naval transport for their
use, and as I was arranging for a passage on a ship of the Peninsular
and Oriental Line we received an invitation to become the guests of
the English party. Among those on board were Professor Tyndall;
Mr. Huggins, the spectroscopist; Sir Erastus Ommaney, a retired
English admiral, and a fellow of the Royal Society; Father Perry,
S. J., a well-known astronomer; and Lieutenant Wharton, who afterward
became hydrographer to the Admiralty.

The sprightliest man on board was Professor Tyndall. He made up
for the absence of mountains by climbing to every part of the ship
he could reach. One day he climbed the shrouds to the maintop,
and stood surveying the scene as if looking out from the top of
the Matterhorn. A sailor followed him, and drew a chalk-line around
his feet. I assume the reader knows what this means; if he does not,
he can learn by straying into the sailors' quarters the first time he
is on board an ocean steamer. But the professor absolutely refused
to take the hint.

We had a rather rough passage