The long tenure of the chair of Astronomy by Brinkley is divided into
two nearly equal periods by the year in which the great circle was
erected. Brinkley was eighteen years waiting for his telescope, and
he had eighteen years more in which to use it. During the first of
these periods Brinkley devoted himself to mathematical research;
during the latter he became a celebrated astronomer. Brinkley's
mathematical labours procured for their author some reputation as a
mathematician. They appear to be works of considerable mathematical
elegance, but not indicating any great power of original thought.
Perhaps it has been prejudicial to Brinkley's fame in this direction,
that he was immediately followed in his chair by so mighty a genius
as William Rowan Hamilton.

After the great circle had been at last erected, Brinkley was able to
begin his astronomical work in earnest. Nor was there much time to
lose. He was already forty-five years old, a year older than was
Herschel when he commenced his immortal career at Slough. Stimulated
by the consciousness of having the command of an instrument of unique
perfection, Brinkley loftily attempted the very highest class of
astronomical research. He resolved to measure anew with his own eye
and with his own hand the constants of aberration and of nutation. He
also strove to solve that great problem of the universe, the
discovery of the distance of a fixed star.

These were noble problems, and they were nobly attacked. But to
appraise with justice this work of Brinkley, done seventy years ago,
we must not apply to it the same criterion as we would think right to
apply to similar work were it done now. We do not any longer use
Brinkley's constant of aberration, nor do we now think that