was gradually abandoned. Fortunately for science Herschel found its
pursuit so attractive that he was led, as his father had been before
him, to give up his whole life to the advancement of knowledge. Nor
was it unnatural that a Senior Wrangler, who had once tasted the
delights of mathematical research, should have been tempted to devote
much time to this fascinating pursuit. By the time John Herschel was
twenty-nine he had published so much mathematical work, and his
researches were considered to possess so much merit, that the Royal
Society awarded him the Copley Medal, which was the highest
distinction it was capable of conferring.

At the death of his father in 1822, John Herschel, with his tastes
already formed for a scientific career, found himself in the
possession of ample means. To him also passed all his father's great
telescopes and apparatus. These material aids, together with a
dutiful sense of filial obligation, decided him to make practical
astronomy the main work of his life. He decided to continue to its
completion that great survey of the heavens which had already been
inaugurated, and, indeed, to a large extent accomplished, by his
father.

The first systematic piece of practical astronomical work which John
Herschel undertook was connected with the measurement of what are
known as "Double Stars." It should be observed, that there are in
the heavens a number of instances in which two stars are seen in very
close association. In the case of those objects to which the
expression "Double Stars" is generally applied, the two luminous
points are so close together that even though they might each be
quite bright enough to be visible to the unaided eye, yet their
proximity is such that they cannot be distinguished as two separate