d he turned his attention in that direction. He was a
walking bibliography of astronomy, which one had only to consult in
order to learn in a moment what great astronomers of recent times had
written on almost any subject, where their work was published, and on
what shelf of the Harvard Library the book could be found. But the
faculty most closely connected with calculation was a quickness and
apprehension of vision, of which the following is an example:--

About 1876 he visited the Naval Observatory in Washington for the
first time in his life. We wanted a certain catalogue of stars and
went together into the library. The required catalogue was on one
of a tier of shelves containing altogether a hundred, or perhaps
several hundred volumes. "I do not know whether we have the book,"
said I, "but if we have, it is on one of these shelves." I began
to go through the slow process of glancing at the books one by one
until my eyes should strike the right title. He stood back six
or eight feet and took in all the shelves seemingly at one glance,
then stepped forward and said, "Here it is." I might have supposed
this an accident, but that he subsequently did practically the same
thing in my office, selecting in a moment a book we wanted to see,
after throwing a rapid glance over shelves containing perhaps a
hundred volumes.

An example of his apprehension and memory for numbers was narrated
by Mr. Alvan Clark. When the latter had completed one of his great
telescopes for the University of Chicago, Safford had been named
as director, and accompanied the three members of the firm to the
city when they carried the object glass thither. On leaving the
train all four took their seats in a hotel omnibus, Safford near
the door. Then they found that they had forgotten to give their
baggage checks to the expressman; so the other three men passed
their checks to Safford, who added his own and handed all four to
the conductor of the omnibus. When it was time for the baggage to
come to the hotel, there was such a crowd of new arrivals that the
attendants could not find it. The hotel clerk remarked on inquiry,
"If I only knew the numbers of your checks, I would have no difficulty
in tracing your trunks." Safford at once told off the four numbers,
which he had read as he was passing the checks to the conductor.

The great fire practically put an end to the activity of the Chicago
Observatory and forced its director to pursue