date of the notes, were Bridge's "Conic Sections," Hutton's
"Mathematics," and Bowditch's "Navigator." At that time Prof. Benjamin
Peirce had not published his "Explanations of the Navigator and
Almanac," so that Maria was obliged to consult many scientific books and
reports before she could herself construct the astronomical tables.

Mr. Mitchell, on relinquishing school-teaching, was appointed cashier of
the Pacific Bank; but although he gave up teaching, he by no means gave
up studying his favorite science, astronomy, and Maria was his willing
helper at all times.

Mr. Mitchell from his early youth was an enthusiastic student of
astronomy, at a time, too, when very little attention was given to that
study in this country. His evenings, when pleasant, were spent in
observing the heavens, and to the children, accustomed to seeing such
observations going on, the important study in the world seemed to be
astronomy. One by one, as they became old enough, they were drafted into
the service of counting seconds by the chronometer, during the
observations.

Some of them took an interest in the thing itself, and others considered
it rather stupid work, but they all drank in so much of this atmosphere,
that if any one had asked a little child in this family, "Who was the
greatest man that ever lived?" the answer would have come promptly,
"Herschel."

Maria very early learned the use of the sextant. The chronometers of all
the whale ships were brought to Mr. Mitchell, on their return from a
voyage, to be "rated," as it was called. For this purpose he used the
sextant, and the observations were made in the little back yard of the