Sir William Herschel arrived in England from Hanover, his birth-place, about the end of the year 1759, when he was in his 21st year. He was bred a professor of music, and went to live at Halifax, where he acquired, by his own application, a considerable knowledge of mathematics; and, having studied astronomy and optics in the popular writings of Ferguson, he was anxious to witness with his own eyes the wonders of the planetary system. He accordingly borrowed of a friend a telescope, two feet in focal length; and, having directed it to the heavens, he was so delighted with the actual sight of phenomena, which he had previously known only from books, that he commissioned a friend to purchase for him in London a telescope, with a high magnifying power. Fortunately for science, the price of such an instrument greatly exceeded his means, and he immediately resolved to construct a telescope with his own hands. After encountering the difficulties which every amateur at first experiences, in the casting, grinding, and polishing, of metallic specula for reflecting telescopes, he completed, in 1776, a reflecting instrument, five feet in focal length, with which he was able to observe the ring of Saturn, and the satellites and belts of Jupiter. This telescope was completed when he resided at Bath, where he acquired by degrees, and in his leisure hours, that practical knowledge of optics and mechanics which was necessary for such a task.

His experience in this scientific art was of the most remarkable kind; and, by 1781, he had constructed so many telescopes, as to be better furnished with the means of surveying the heavens than were possessed by any other astronomer, in either of the fixed observatories in Europe.