ical genius came to his aid. Having purchased the apparatus of a
Quaker optician, he set about the manufacture of specula with a zeal
which seemed to anticipate the wonders they were to disclose to him. It
was not until fifteen years later that his grinding and polishing
machines were invented, so the work had at that time to be entirely done
by hand. During this tedious and laborious process (which could not be
interrupted without injury, and lasted on one occasion sixteen hours),
his strength was supported by morsels of food put into his mouth by his
sister,[10] and his mind amused by her reading aloud to him the Arabian
Nights, Don Quixote, or other light works. At length, after repeated
failures, he found himself provided with a reflecting telescope--a
5-1/2-foot Gregorian--of his own construction. A copy of his first
observation with it, on the great Nebula in Orion--an object of
continual amazement and assiduous inquiry to him--is preserved by the
Royal Society. It bears the date March 4, 1774.[11]

In the following year he executed his first "review of the heavens,"
memorable chiefly as an evidence of the grand and novel conceptions
which already inspired him, and of the enthusiasm with which he
delivered himself up to their guidance. Overwhelmed with professional
engagements, he still contrived to snatch some moments for the stars;
and between the acts at the theatre was often seen running from the
harpsichord to his telescope, no doubt with that "uncommon precipitancy
which accompanied all his actions."[12] He now rapidly increased the
power and perfection of his telescopes. Mirrors of seven, ten, even
twenty feet focal length, were successively completed, and unprecedented
magnifying powers employed. His energy was unceasing, his perseverance
indomitable. In the course of twenty-one years no less than 430
parabolic specula left his hands. He had entered upon his forty-second
year when he sent his first paper to the _Philosophical Transactions_;
yet during the ensuing thirty-nine years his contributions--many of them
elaborate treatises--numbered sixty-nine, forming a series of
extraordinary importance to the history of astronomy. As a mere explorer
of the heavens his labours were prodigious. He discovered 2,500 nebulae,
806 double stars, passed the whole firmament in review four several
times, counted the stars in 3,400 "gauge-fields," and executed a
photometric classification of the principal stars, founded on