HERSCHEL’S FINDS

Evening Star, Issue 21641, 9 February 1934, Page 11

HERSCHEL’S FINDS

PIONEER ASTRONOMER WORK OH FIXED STARS REWARD OF TENACITY Orie : of the '"outstanding figures of British astronomy-, is, that of Frederick ■William Herschel, “the elder Her•chel,” to'distinguish him from his celebrated son, John Frederick William Herschel, “ the younger Herschel,” who carried on his father’s "work through the middle of last century, says a writer in the Melbourne ‘Age.’ Particularly in recent years, when the structure of the universe has been one of the great questions of astronomy, do we come more and more to admire the Work of William Herschel, for he it was that first had the clear idea that the fixed stars form a system with a definite structure, and that it was worth while to study this structure, basing the investigation on actual observations. Others before him, Kepler and .Huygens, for example, had suggested' that the sun was a star, and • that the stars were suns attended by planetary systems. Kant and Lambert had built up systems of the world, which, however, were not- based on observation, but were entirely speculative.. The only certain information when Herschel began his work was Galileo’s observation that the Milky Way consisted of many stars. Herschel started right from the very beginning, for the telescopes with which he worked were constructed by himself, and his conclusions were based on his own observations, for, as he says, “ I determined to accept nothing on faith, but to see with my own eyes what others had seen before me.” The amount of ■ observing he carried out was prodigious, for it was his custom to work throughout the night if the sky remained clear, and to make use of every moment that he could at the telescope. When we think of the conditions under which he worked, out in the open through a long and cold winter’s night, with a telescope which had none of the conveniences of movement of modern instruments, we can only wonder at the amount of observing he accomplished, and admire the fortitude of his sister, Caroline, whose devoted assistance throughout ids observing must have helped so greatly in his accomplishment. A MUSICIAN. Frederick William Herschel was born at Hanover on November 15, 1738. His father was a musician in the Hanoverian army, and as a youth the son, who showed a remarkable aptitude for music, obtained a position as a regular performer in the regimental band of the Hanoverian Guards. He saw active service in the Battle of Hastenbeck, but the experience was not to his liking. He deserted, and succeeded in eluding capture and reaching England in safety. For some years he managed to gain a precarious living, but at the age of twenty-two he obtained his first regular employment as instructor of music to the Durham Militia. Shortly afterwards lie became organist at the parish church at Halifax. In 1766 he moved to Bath, then a highly fashionable resort, first as oboist in the orchestra, then as organist in the Octagon Chapel. It was not very long after tin’s that he became interested in astronomy. He started with a small reflecting telescope which he hired, but soon he wished for a larger one. The cost was far beyond his means, so that ho planned to construct his own telescope. With wonderful application ho earned this through, learning to cast, grind, and.polish the mirrors himself. In this he was helped by his brother Alexander and by his devoted sister Caroline. The latter, whom he Had brought over from Hanover in 1772, not only kept house for him, but rendered him assistance in many ways.

Herschel, with characteristic energy, devoted all his spare time to work on his mirrors. On one occasion bis band never left 'the polishing tool for .sixteen hours, during which time Caroline was “obliged to feed him by putting the victuals by bits iuto his mouth.”. Often

she read to him while he was engaged in this work. We are glad to note that among the books that were read were ‘ Don Quixote,’ the ‘ Arabian Nights,’ and the novels of Sterne and Fielding. BONE AT LAST. After many failures Herschel completed a tolerable reflecting telescope, with which, in March, 1774, he made his first recorded observation. After this, night after night, as soon as his musical labours were ended, his telescope was brought out, sometimes into the back garden of ills house at Bath, sometimes into the street in- front of his hall door. He was always trying to improve his equipment, making fresh mirrors or trying new lenses as eyepieces, or perhaps altering the mounting of his telescope. His sister complained that sometimes he came in from his conducting, and without taking time to remove his lace ruffles, he would set to work at his polishing, and soon, his ruffles were soiled with pitch. At Bath, Herschel started on a systematic examination of all the stars above a certain brightness. At the same time lie was engaged on making larger and larger telescopes for himself; first one 7ft in length, then one 10ft, and at last one 2Uft long, the diameter of the mirror of the last being 18iu, In the course of the second survey with his 7ft telescope, he made his first notable discovery on March 13, 1781, a discovery which brought him a European reputation and enabled him to devote his whole time to astronomy and to the manufacture of telescopes. To use his own words, “ In examining the small stars in the neighbourhood of H. Geminorum, 1 perceived one that appeared visibly larger than the rest; being struck with its uncommon appearance, I compared it to H. Geminorum and the small star in the quartile between Auriga and Gemini, and finding it so much larger than either of them, 1 suspected it to be a comet.” A NEW PLANET. Within three or four months of its discovery, however, it was announced b.v Lexcli that it was not a comet, but a new planet, moving in a nearly circular orbit round the sun and outside the orbit of Saturn. Herschel. as its discoverer, named i.t Georgium Sides, but this name was never favoured on Continent. Finally, the suggestion that it bo named Uranus, in conformity with the nomenclature of the ancient planets, was made and has been universally accepted. This discovery, the first discovery of a planet in historical times, brought fame to Herschel. Before the end of the year he was elected a follow the Royal Society, receiving the Copley medal, ami in the following year he was summoned to Court to exhibit his telescopes and stars to George 111. At his first appearance the King handed him a free pardon for his desertion of a quarter of a century before. The King appointed him Royal astronomer, at a salary of £2OO a year, and also gave Caroline a salary as his assistant. In August, 1782, they left Bath, and moved first to Datchct; then after u few months spent at Clay Hill, in Old Windsor, to Slough, to the house now known as Observatory House. At the end of 1783 bo bad completed his 20-foot telescope, with which most of his important work was done. In 1785 a grant from the King enabled him to commence a still lamer one, with a 4ft mirror, and a tube 40ft long, which was used for the first time on August 28, 1789. On that evening Herschel definitely saw a sixth satellite to Saturn, which he had suspected two years before, and three weeks later he discovered a seventh. THE 40-FOOT TELESCOPE. Obseiving with this 40-foot telescope must have been very strenuous work, and one can only wonder that Herschel was able to observe with it hour after tioui throughout the long winter’s night as he did. and be thankful 'that so few serious accidents occurred. There was a complicated framework that supported the telescope, and long ladders up which ho had to climb to the observing platform at the upper end of the telescope tube. Here lie would be exposed to the wind, and, without any of the facilities for the easy movement of the telescope, which make modern observing so convenient by comparison, cany out bis arduous work, ’flic telescope could be moved in altitude by means of a block and tackle, and the whole structure, housing supports and telescope, raft round

on a circular track, so that the telescope could be turned to any point of the compass.

In 1788, not very long before the 40ft telescope was completed, Herschel married the widow of John Pit. a wealthy London merchant, and thus was freed from financial worries. Caroline moved to lodgings close to her brother, but continued to assist him in his work, and at times carried on observational work herself. As a result of her observations she discovered no fewer than eight comets, surely a, remarkable result when one considers how many of the limited number of nights on which observing was possible were taken up with helping her brother. Night after night ho observed, and day after day he devoted to interpreting his observations. The ultimate aim of all his work was to, gain some knowledge of the structure of the universe, and paper after paper came from his pen. It is impossible in this biographical notice to dwell on his results; that would be more fitting for a separate article. Herschel observed assiduously till the opening of 1807, when he had a serious illness, after which his health remained delicate and forced him to devote a larger proportion of his time to indoor work. In 1811 he ceased to use the big telescope, for the surface of the mirror had deteriorated, and his hand was no longer equal to the delicate task of repolishing ’it. His last paper was a list of double stars, and was contributed to the newly-Joundcd Royal Astronomical Society in 1821. He died on August 21, 1822, in his eightyfourth year. After his death Caroline returned to Hanover, where she continued to reside until her death in 1848, in her ninety-eighth year.