Herschel’s Epitaph.
251. Frederick William Herschel was born at Hanover on November 15th, 1738, two years after Lagrange and nine years before Laplace. His father was a musician in the Hanoverian army, and the son, who shewed a remarkable aptitude for music as well as a decided taste for knowledge of various sorts, entered his father’s profession as a boy (1753). On the breaking out of the Seven Years’ War he served during part of a campaign, but his health being delicate his parents “determined to remove him from the service—a step attended by no small difficulties,” and he was accordingly sent to England (1757), to seek his fortune as a musician.
After some years spent in various parts of the country, he moved (1766) to Bath, then one of the great centres of fashion in England. At first oboist in Linley’s orchestra, then organist of the Octagon Chapel, he rapidly rose to a position of great popularity and distinction, both as a musician and as a music-teacher. He played, conducted, and composed, and his private pupils increased so rapidly that the number of lessons which he gave was at one time 35 a week. But this activity by no means exhausted his extraordinary energy; he had never lost his taste for study, and, according to a contemporary biographer, “after a fatiguing day of 14 or 16 hours spent in his vocation, he would retire at night with the greatest avidity to unbend the mind, if it may be so called, with a few propositions in Maclaurin’s Fluxions, or other books of that sort.” His musical studies had long ago given him an interest in mathematics, and it seems likely that the study of Robert Smith’s Harmonics led him to the Compleat System of Optics of the same author, and so to an interest in the construction and use of telescopes. The astronomy that he read soon gave him a desire to see for himself what the books described; first he hired a small reflecting telescope, then thought of buying a larger instrument, but found that the price was prohibitive. Thus he was gradually led to attempt the construction of his own telescopes (1773). His brother Alexander, for whom he had found musical work at Bath, and who seems to have had considerable mechanical talent but none of William’s perseverance, helped him in this undertaking, while his devoted sister Caroline (1750-1848), who had been brought over to England by William in 1772, not only kept house, but rendered a multitude of minor services. The operation of grinding and polishing the mirror for a telescope was one of the greatest delicacy, and at a certain stage required continuous labour for several hours. On one occasion Herschel’s hand never left the polishing tool for 16 hours, so that “by way of keeping him alive” Caroline was “obliged to feed him by putting the victuals by bits into his mouth,” and in less extreme cases she helped to make the operation less tedious by reading aloud: it is with some feeling of relief that we hear that on these occasions the books read were not on mathematics, optics, or astronomy, but were such as Don Quixote, the Arabian Nights, and the novels of Sterne and Fielding.
252. After an immense number of failures Herschel succeeded in constructing a tolerable reflecting telescope—soon to be followed by others of greater size and perfection—and with this he made his first recorded observation, of the Orion nebula, in March 1774.
This observation, made when he was in his 36th year, may be conveniently regarded as the beginning of his astronomical career, though for several years more music remained his profession, and astronomy could only be cultivated in such leisure time as he could find or make for himself; his biographers give vivid pictures of his extraordinary activity during this period, and of his zeal in using odd fragments of time, such as intervals between the acts at a theatre, for his beloved telescopes.
A letter written by him in 1783 gives a good account of the spirit in which he was at this time carrying out his astronomical work:—
“I determined to accept nothing on faith, but to see with my own eyes what others had seen before me.... I finally succeeded in completing a so-called Newtonian instrument, 7 feet in length. From this I advanced to one of 10 feet, and at last to one of 20, for I had fully made up my mind to carry on the improvement of my telescopes as far as it could possibly be done. When I had carefully and thoroughly perfected the great instrument in all its parts, I made systematic use of it in my observations of the heavens, first forming a determination never to pass by any, the smallest, portion of them without due investigation.”
In accordance with this last resolution he executed on four separate occasions, beginning in 1775, each time with an instrument of greater power than on the preceding, a review of the whole heavens, in which everything that appeared in any way remarkable was noticed and if necessary more carefully studied. He was thus applying to astronomy methods comparable with those of the naturalist who aims at drawing up a complete list of the flora or fauna of a country hitherto little known
253. In the course of the second of these reviews, made with a telescope of the Newtonian type, 7 feet in length, he made the discovery (March 13th, 1781) which gave him a European reputation and enabled him to abandon music as a profession and to devote the whole of his energies to science.
“In examining the small stars in the neighbourhood of η Geminorum I perceived one that appeared visibly larger than the rest; being struck with its uncommon appearance I compared it to η Geminorum and the small star in the quartile between Auriga and Gemini and finding it so much larger than either of them, I suspected it to be a comet.”