John Herschel

“ THE 40-FOOT TELESCOPE AS IT WAS IN THE YEAR 1863, HERSCHEL HOUSE, SLOUGH.
Herschel married when considerably advanced in life and he lived to enjoy the indescribable pleasure of finding that his only son, afterwards Sir John Herschel, was treading worthily in his footsteps, and attaining renown as an astronomical observer, second only to that of his father. The elder Herschel died in 1822, and his illustrious sister Caroline then returned to Hanover, where she lived for many years to receive the respect and attention which were so justly hers. She died at a very advanced age in 1848. ”

“ MISS CAROLINE LUCRETIA HERSCHEL. This very interesting lady died at Hanover on the 9th of January, 1848, in the 98th year of her age. She was the sister of Sir William Herschel; and consequently, aunt to Sir John Herschel, the present representative of this truly scientific family.
Miss Herschel was the constant companion of her brother, and sole assistant of his astronomical labours, to the success of which her indefatigable zeal, diligence, and singular accuracy of calculation, not a little contributed. ”

“ It answered perfectly with a telescope which magnified 100 times, and a microscope of about thrice that power.
Sir John Herschel then conceived the stupendous fabric of his present telescope. The power of his father's instrument would still leave him distant from his favorite planet nearly forty miles, and he resolved to attempt a greater magnifier. Money, the wings of science as the sinews of war, seemed the only requisite, and even the acquisition of this, which is often more difficult than the task of Sisyphus, he determined to achieve. ”

“ Sir John Herschel, in completion of the work of his father, who had made the catalogue of the stars of the northern hemisphere, expatriated himself for years at the Cape of Good Hope, finished his inventory of the southern heaven, came home, and redacted it in eight years more; – a work whose value does not begin until thirty years have elapsed, and thenceforward a record to all ages of the highest import. ”

“ Boyle's place in science should be estimated by the relation of his work to his time, not to ours. He was a leader, much in advance. Sir John Herschel says that he "seemed animated by an enthusiasm of ardor, which hurried him from subject to subject, and from experiment to experiment, without a moment's intermission, and with a sort of undistinguishing appetite." Sir Henry W. Ackland suggests that he had so many qualities, and pursued so many lines of thought, that they almost dim one another. ”

“ A “Requiem,” composed by Sir John Herschel, was sung by his family, fourteen in number, assembled within the tube, which was then riveted up and laid horizontally on three stone piers in the garden at Slough. “It looks very well in its new position,” Sir John thought. Yet it has something of a memento mori aspect. It seems to remind one that the loftiest human aspirations are sprinkled “with the dust of death.” The speculum adorns the hall of Observatory House. ”

“ Sir John Herschel remembers his father saying, 'If that hypothesis were true, and if the planet destroyed were as large as the earth, there must have been at least thirty-thousand such fragments,' but always as an hypothesis—he was never heard to declare any degree of conviction that it was so."
For us, the value of this sympathetic account of a day in Herschel's life is in its conception of the simplicity, the modesty, the "boyish earnestness," the elevation of thought and speech of the old philosopher ”

“ But for this moral purpose, he might have squandered time in a multiplicity of partial researches. So late as 1830 he told Sir William Rowan Hamilton: “I find it impossible to dwell for very long on one subject, and this renders my pursuit of any branch of science necessarily very desultory.” His nebulæ and double stars saved him from being “everything by turns, and nothing long.” Their collection and revisal, begun as a duty, grew to be irresistibly attractive, and John Herschel pledged himself definitively to astronomy. ”

“ First—to get my sister and myself out of the way—there were we two. In the drawing of lots, my sister drew her own room, and I drew Master B.'s. Next, there was our first cousin John Herschel, so called after the great astronomer: than whom I suppose a better man at a telescope does not breathe. With him, was his wife: a charming creature to whom he had been married in the previous spring. I thought it (under the circumstances) rather imprudent to bring her, because there is no knowing what even a false alarm may do at such a time ”

“ John Herschel possessed this endowment to a large extent; and he solaced his declining years with the translation of the Iliad into verse, having earlier executed a similar version of Schiller’s Walk. But the main work of his later life was the collection of all his father’s catalogues of nebulae and double stars combined with his own observations and those of other astronomers each into a single volume. He lived to complete the former, to present it to the Royal Society, and to see it published in a separate form in the Philosophical Transactions, vol. cliv. ”

“ That society printed a portion of it, which serves as an index to the observations of various astronomers on double stars up to the year 1866.
A complete list of his contributions to learned societies will be found in the Royal Society’s great catalogue, and from them may be gathered most of the records of his busy scientific life. Sir John Herschel met with an amount of public recognition which was unusual in the time of his illustrious father. Naturally he was a member of almost every important learned society in both hemispheres. ”

“ Besides the laborious Cape Observations, Sir John Herschel was the author of several books, one of which at least, On the Study of Natural Philosophy (1830) , possesses an interest which no future advances of the subjects on which he wrote can obliterate. In 1849 came the Outlines of Astronomy, a volume still replete with charm and instruction. ”

“ He was succeeded in the baronetcy by his eldest son, Sir William James Herschel; his second son, Professor Alexander Stewart Herschel, is well known as an astronomer and physicist; Colonel John Herschel, his third son, was elected a fellow of the Royal Society in 1871, in recognition of his spectroscopic examination of southern nebulæ. Eight of Herschel's nine daughters are still (1891) living. ”

“ A few traits of John Herschel's boyhood, mentioned by himself in his maturer life, have been treasured up by those who were dear to him, and the record of some of them may satisfy a curiosity as pardonable as inevitable, which craves to learn through what early steps great men or great nations become illustrious. ”

“ Sir John Herschel, son of the illustrious astronomer, undertook the preparation of the address to the friends of astronomy "It may seem strange," he said in the beginning, "that in a country like Great Britain, where science is generally carefully cultivated, and where astronomy has made great progress and drawn upon itself a large share of attention, there should exist no society occupied especially with that science ”

“ It perpetuates, indeed, the countenance of a man replete with human tenderness.
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CHAPTER X.
WRITINGS AND EXPERIMENTAL INVESTIGATIONS. Could the whole of Sir John Herschel’s astronomical career be obliterated, and the whole of his contributions to pure mathematics be forgotten, he would still merit celebrity as a physicist. Experimental optics, above all, engaged his attention. “Light,” he himself said, “was his first love,” and he was never wholly forgetful of it. In 1830 he described himself as “forcibly drawn aside from his optical studies” by the claims of nebulæ and double stars. ”

“ An idea of the position accorded to Oersted by his colleagues in the world of science may be gathered from an address made by Sir John Herschel at the closing session of the Southampton meeting of the British Association in 1836, in which the distinguished astronomer said: "In science, there is but one direction which the needle will take when pointed towards the European continent, and that is towards my esteemed friend, Professor Oersted. ”

“ Sir John Herschel has the following admirable remarks, which are very much to our present purpose. "What mere assertion will make any one believe, that in one second of time, in one beat of a pendulum of a clock, a ray of light travels over 192,000 Miles, and would therefore perform the tour {383} of the world in about the same time that it requires to wink with our eyelids, and in much less than a Swift runner occupies in taking a single stride? What mortal can be made to believe, without demonstration, that the sun is almost a million times larger than the earth? ”

“ Ruder blows were required to shatter an hypothesis flattering to human pride of invention in its completeness, in the plausible detail of observations by which it seemed to be supported, and in its condescension to the natural pleasure in discovering resemblance under all but total dissimilarity.
Sir John Herschel included among the results of his multifarious labours at the Cape of Good Hope a careful study of the sun-spots conspicuously visible towards the end of the year 1836 and in the early part of 1837. ”

“ Arrived at manhood at the opening of the present century, having been born in 1781, he continued his brilliant course during fifty years, pursuing his investigations into the laws of polarisation by crystals, and by the reflection, refraction, and absorption of light, in which he made important discoveries. The attention of the British public was forcibly arrested by an able treatise on "Light," contributed by Sir John Herschel, in 1827, to the "Encyclopædia Metropolitana." ”

“ It is in astronomy as in another field of exploration. The footsteps of the pioneer settler in a new land are soon effaced by the tread of his successors. They settle, flourish, improve on the spot which he painfully toiled to attain. But though he has laboured, and others have entered into his labour, to the pioneer belongs the honour and the fame. So it is with William Herschel. Sir John Herschel traversed the whole field opened by his father, besides a new one of his own. He worked on his father's lines with appliances such as had not been within his father's reach. ”

“ The metal tube of the instrument, carrying at one end the recently cleaned mirror of four feet ten inches in diameter, has been placed horizontally in the meridian line, on solid piles of masonry, in the midst of the circle where the apparatus used in manoeuvring it was formerly placed. On the 1st of January 1840, Sir John Herschel, his wife, their seven children, and some old family servants, assembled at Slough. Exactly at noon the party walked several times in procession round the instrument ”

“ Airy at this time was again absent on the Continent; the British Association met; Adams came with his paper, but the section of mathematics and physics had adjourned the day before he arrived. Had he been present at the beginning of the meeting he would have heard Sir John Herschel say in his address on resigning the chair to his successor, after referring to the astronomical events of the year, which included a discovery of a new minor planet: "The year has done more. It has given us the probable prospect of the discovery of another planet. ”

“ The allusion made by Sir John Herschel, in his letter contained in the Athenæum of October 3, to the theoretical researches of Mr. Adams, respecting the newly-discovered planet, has induced me to request that you would make the following communication public. It is right that I should first say that I have Mr. Adams's permission to make the statements that follow, so far as they relate to his labors. I do not propose to enter into a detail of the steps by which Mr. Adams was led, by his spontaneous and independent researches, to a conclusion that a planet must exist more distant than Uranus. ”

“ I afterwards sent him a present of some of my drawings. He answered: "A thousand thanks for the charming etchings. I am especially interested in Robinson Crusoe. He looks very comfortable, but I can't see his bed, which troubles me. The election ('Everybody for ever!') is wonderful. I should not like to be there. I hope we shall go to you again one of these days, and have another peep into that wonderful telescope."
To return to Sir John Herschel, We returned his visit at his house at Collingwood, near Hawkhurst. ”

“ I only wished you to have some for your own friends, Mr. South, Major Kater, &c., for as they were not members of the R. Society at the time of publication, they may perhaps not be possessed of that necessary Appendix.
The next messenger will take the book Mr. Babbage wishes for, and I want very much to send you some of the numerous philosophical productions in which this country my nephew Groskopf says abounds, but I am at a loss on what to fix my choice. I wish you would let me know if any of the works of Schelling are known in England? ”

“ These memorials of his father and his aunt were viiimuch valued by Sir John Herschel, and they are carefully preserved by the family along with her letters. The perusal of them is like reading of another world. The glimpses of the life of a soldier’s family in Hanover at the time the Seven Years’ War was going on are very touching. Both father and mother must have been remarkable persons, and the sterling quality of character developed in William and Caroline Herschel was evidently derived from them. ”

“ The latitude of the Cape of Good Hope is such that a suitable site could be there found for his purpose. The purity of the skies in South Africa promised to provide for the astronomer those clear nights which his delicate task of surveying the nebulae would require.
On November 13, 1833, Sir John Herschel, who had by this time received the honour of knighthood from William IV., sailed from Portsmouth for the Cape of Good Hope, taking with him his gigantic instruments. ”