Читать книгу The Herschels and Modern Astronomy - Agnes M. Clerke - Страница 8

Table of Contents

William Herschel was now an appendage to the court of George III. He had to live near Windsor, and a large dilapidated house on Datchet Common was secured as likely to meet his unusual requirements. The “flitting” took place August 1, 1782. William was in the highest spirits. There were stables available for workrooms and furnaces; a spacious laundry that could be turned into a library; a fine lawn for the accommodation of the great reflector. Crumbling walls and holes in the roof gave him little or no concern; and if butcher’s meat was appallingly dear (as his sister lamented) the family could live on bacon and eggs! In this sunny spirit he entered upon the career of untold possibilities that lay before him.

Nevertheless the King’s astronomer did not find it all plain sailing. His primary duty was to gratify the royal taste for astronomy, and this involved no trifling expenditure of time and toil. The transport of the seven-foot to the Queen’s lodge could be managed in the daylight, but its return-journey in the dark, after the conclusion of the celestial raree-show, was an expensive and a risky business; yet fetched back it should be unless a clear night were to be wasted—a thing not possible to contemplate. This kind of attendance was, however, considerately dispensed with when its troublesome nature came to be fully understood. Herschel’s treatment by George III. has often been condemned as selfish and niggardly; but with scant justice. In some respects, no doubt, it might advantageously have been modified. Still, the fact remains that the astronomer of Slough was the gift to science of the poor mad King. From no other crowned head has it ever received so incomparable an endowment.

Herschel’s salary was undeniably small. It gave him the means of living, but not of observing, as he proposed to observe. If the improvement of telescopes were to be “carried to its utmost limit,” additional funds must be raised. Without an ample supply of the “sinews of war,” fresh campaigns of exploration were out of the question. There was one obvious way in which they could be provided. Herschel’s fame as an optician was spread throughout Europe. His telescopes were wanted everywhere, but could be had from himself alone; for the methods by which he wrought specula to a perfect figure are even now undivulged. They constituted, therefore, a source of profit upon which he could draw to almost any extent. He applied himself, accordingly, to make telescopes for sale. They brought in large sums. Six hundred guineas a-piece were paid to him by the King for four ten-foot reflectors; he received at a later date £3,150 for a twenty-five foot, sent to Spain; and in 1814 £2,310 from Lucien Bonaparte for two smaller instruments. The regular scale of prices (later considerably reduced) began with 200 guineas for a seven-foot, and mounted to 2,500 for a twenty-foot; and the commissions executed were innumerable.

But Herschel did not come into the world to drive a lucrative trade. It was undertaken, not for itself, but for what was to come of it; yet there was danger lest the end should be indefinitely postponed in the endeavour to secure the means.

“It seemed to be supposed,” Miss Herschel remarked, “that enough had been done when my brother was enabled to leave his profession that he might have time to make and sell telescopes. But all this was only retarding the work of a thirty or forty-foot instrument, which it was his chief object to obtain as soon as possible; for he was then on the wrong side of forty-five, and felt how great an injustice he would be doing to himself and the cause of astronomy by giving up his time to making telescopes for other observers.”

This he was, fortunately, not long obliged to do. A royal grant of £2,000 for the construction of the designed giant telescope, followed by another of equal amount, together with an annual allowance of £200 for its repairs, removed the last obstacle to his success. The wide distribution of first-class instruments might, indeed, have been thought to promise more for the advancement of astronomy than the labours of a single individual. No mistake could be greater. Not an observation worth mentioning was made with any of the numerous instruments sent out from Datchet or Slough, save only those acquired by Schröter and Pond. The rest either rusted idly, or were employed ineffectually, aptly illustrating the saying that “the man at the eye-end” is the truly essential part of a telescope.

No one knew this better than Herschel. Every serene dark night was to him a precious opportunity availed of to the last minute. The thermometer might descend below zero, ink might freeze, mirrors might crack; but, provided the stars shone, he and his sister worked on from dusk to dawn. In this way, his “third review,” begun at Bath, was finished in the spring of 1783. The swiftness with which it was conducted implied no want of thoroughness. “Many a night,” he states, “in the course of eleven or twelve hours of observation, I have carefully and singly examined not less than 400 celestial objects, besides taking measures, and sometimes viewing a particular star for half an hour together, with all the various powers.”

The assiduity appears well-nigh incredible with which he gathered in an abundant harvest of nebulæ and double stars; his elaborate papers, brimful of invention and experience, being written by day, or during nights unpropitious for star-gazing. On one occasion he is said to have worked without intermission at the telescope and the desk for seventy-two hours, and then slept unbrokenly for twenty-six hours. His instruments were never allowed to remain disabled. They were kept, like himself, on the alert. Relays of specula were provided, and one was in no case removed from the tube for re-polishing, unless another was ready to take its place. Even the meetings of the Royal Society were attended only when moonlight effaced the delicate objects of his particular search.

The summer of 1788 was spent in getting ready the finest telescope Herschel had yet employed. It was called the “large twenty-foot” because of the size of its speculum, which was nearly nineteen inches in diameter; and with its potent help he executed his fourth and last celestial survey. His impatience to begin led him into perilous situations.

“My brother,” says Miss Herschel, “began his series of sweeps when the instrument was yet in a very unfinished state; and my feelings were not very comfortable when every moment I was alarmed by a crack or fall, knowing him to be elevated fifteen feet or more on a temporary cross-beam instead of a safe gallery. The ladders had not even their braces at the bottom; and one night, in a very high wind, he had hardly touched the ground before the whole apparatus came down. Some labouring men were called up to help in extricating the mirror, which was fortunately uninjured, but much work was cut out for carpenters next day.”

In the following March, he himself wrote to Patrick Wilson, of Glasgow, son of Dr. Alexander Wilson, the well-known professor of astronomy:—“I have finished a second speculum to my new twenty-foot, very much superior to the first, and am now reviewing the heavens with it. This will be a work of some years; but it is to me so far from laborious that it is attended with the utmost delight.” He, nevertheless, looked upon telescopes as “yet in their infant state.”

The ruinous mansion at Datchet having become uninhabitable, even by astronomers, their establishment was shifted, in June, 1785, to Clay Hall, near Old Windsor. Here the long-thought-of forty-foot was begun, but was not destined to be finished. A litigious landlady intervened. The next move, however, proved to be the last. It was to a commodious residence at Slough, now called “Observatory House”—“le lieu du monde,” wrote Arago, “où il a été fait le plus de découvertes.” Thither, without the loss of an hour, in April, 1786, the machinery and apparatus collected at Clay Hall were transported. Yet, “amidst all this hurrying business,” Caroline remembered “that every moment after daylight was allotted to observing. The last night at Clay Hall was spent in sweeping till daylight, and by the next evening the telescope stood ready for observation at Slough.”

During the ensuing three months, thirty to forty workmen were constantly employed, “some in felling and rooting out trees, some in digging and preparing the ground for the bricklayers who were laying the foundation for the telescope.” “A whole troop of labourers” were, besides, engaged in reducing “the iron tools to a proper shape for the mirror to be ground upon.” Thus, each morning, when dawn compelled Herschel to desist from observation, he found a bevy of people awaiting instructions of all sorts from him. “If it had not been,” his sister says, “for the intervention of a cloudy or moonlit night, I know not when he, or I either, should have got any sleep.” The wash-house was turned into a forge for the manufacture of specially designed tools; heavy articles cast in London were brought by water to Windsor; the library was so encumbered with stores, models, and implements, that “no room for a desk or an atlas remained.”

On July 3rd, 1786, Herschel, accompanied by his brother Alexander, started for Göttingen, commissioned by the King to present to the University one of the ten-foot reflectors purchased from him. He was elected a Member of the Royal Society of Göttingen, and spent three weeks at Hanover with his aged mother, whom he never saw again. During his absence, however, the forty-foot progressed in accordance with the directions he had taken care to leave behind. He trusted nothing to chance. “There is not one screwbolt,” his sister asserted, “about the whole apparatus but what was fixed under the immediate eye of my brother. I have seen him lie stretched many an hour in a burning sun, across the top beam, whilst the iron-work for the various motions was being fixed. At one time no less than twenty-four men (twelve and twelve relieving each other) kept polishing day and night; my brother, of course, never leaving them all the while, taking his food without allowing himself time to sit down to table.”

At this stage of the undertaking it became the fashion with visitors to use the empty tube as a promenade. Dr. and Miss Burney called, in July, 1786, “to see, and take a walk through the immense new telescope.” “It held me quite upright,” the authoress of “Evelina” related, “and without the least inconvenience; so would it have done had I been dressed in feathers and a bell-hoop.”

George III. and the Archbishop of Canterbury followed the general example; and the prelate being incommoded by the darkness and the uncertain footing, the King, who was in front, turned back to help him, saying: “Come, my lord bishop, I will show you the way to heaven.” On another occasion “God save the King” was sung and played within the tube by a large body of musicians; and the rumour went abroad that it had been turned into a ball-room!

The University of Oxford conferred upon Herschel, in 1786, an honorary degree of LL.D.; but he cared little for such distinctions. Miss Burney characterised him as a “man without a wish that has its object in the terrestrial globe;” the King had “not a happier subject.” The royal bounty, she went on “enables him to put into execution all his wonderful projects, from which his expectations of future discoveries are so sanguine as to make his present existence a state of almost perfect enjoyment.” Nor was it possible to “admire his genius more than his gentleness.” Again, after taking tea in his company in the Queen’s lodge: “this very extraordinary man has not more fame to awaken curiosity than sense and modesty to gratify it. He is perfectly unassuming, yet openly happy; and happy in the success of those studies which would render a mind less excellently formed presumptuous and arrogant.” Mrs. Papendick, another court chronicler, says that “he was fascinating in his manner, and possessed a natural politeness, and the abilities of a superior nature.”

His great telescope took rank, before and after its completion, as the chief scientific wonder of the age. Slough was crowded with sightseers. All the ruck of Grand Dukes and Serene Highnesses from abroad, besides royal, noble, and gentle folk at home, flocked to gaze at it and interrogate its maker with ignorant or intelligent wonder. The Prince of Orange was a particularly lively inquirer. On one of his calls at Slough, about ten years after the erection of the forty-foot, finding the house vacant, he left a memorandum asking if it were true, as the newspapers reported, that “Mr. Herschel had discovered a new star whose light was not as that of the common stars, but with swallow-tails, as stars in embroidery?”!

Pilgrim-astronomers came, too—Cassini, Lalande, Méchain and Legendre from Paris, Oriani from Milan, Piazzi from Palermo. Sniadecki, director of the observatory of Cracow, “took lodgings,” Miss Herschel relates, “in Slough, for the purpose of seeing and hearing my brother whenever he could find him at leisure. He was a very silent man.” One cannot help fearing that he was also a very great bore. Von Magellan, another eminent foreign astronomer, communicated to Bode an interesting account of Herschel’s methods of observation. The multitude of entries in his books astonished him. In sweeping, he reported, “he lets each star pass at least three times through the field of his telescope, so that it is impossible that anything can escape him.” The thermometer in the garden stood that night, January 6th, 1785, at 13 deg. Fahrenheit; but the royal astronomer, his visitor remarked, “has an excellent constitution, and thinks about nothing else in the world but the celestial bodies.”

In January, 1787, Herschel made trial with his twenty-foot reflector of the “front-view” plan of construction, suggested by Lemaire in 1732, but never before practically tested. All that had to be done was to remove the small mirror, and slightly tilt the large one. The image was then formed close to the upper margin of the tube, into which the observer, turning his back to the heavens, looked down. The purpose of the arrangement was to save the light lost in the second reflection; and its advantage was at once illustrated by the discovery of two Uranian moons—one (Titania) circling round its primary in about 8¾ hours, the other (Oberon) in 13½ hours. In order to assure these conclusions, he made a sketch beforehand of what ought to be seen on February 10th; and on that night, to his intense satisfaction, “the heavens,” as he informed the Royal Society, “displayed the original of my drawing by showing, in the situation I had delineated them, the Georgian planet attended by two satellites. I confess that this scene appeared to me with additional beauty, the little secondary planets seeming to give a dignity to the primary one which raises it into a more conspicuous situation among the great bodies of our solar system.”

This brilliant result determined him to make a “front-view” of the forty-foot. Its advance towards completion was not without vicissitudes. The first speculum, when put into the tube, February 19th 1787, was found too thin to maintain its shape. A second, cast early in 1788, cracked in cooling. The same metal having been recast February 16th, the artist tried it upon Saturn in October; but the effect disappointing his expectation, he wrought at it for ten months longer. At last, after a few days’ polishing with his new machine, he turned the great speculum towards Windsor Castle; when its high quality became at once manifest. And such was his impatience to make with it a crucial experiment, that—as he told Sir Joseph Banks—he directed it to the heavens (August 28th, 1789) before it had half come to its proper lustre. The stars came out well, and no sooner had he got hold of Saturn than a sixth satellite stood revealed to view! Its “younger brother” was detected September 17th; and the two could be seen, on favourable opportunities, threading their way, like beads of light, along the lucid line of the almost vanished ring. Herschel named them Enceladus and Mimas, and found, on looking up his former observations of Saturn, that Enceladus, the exterior and brighter object, had been unmistakably seen with the twenty-foot, August 19th, 1787. Mimas is a very delicate test of instrumental perfection.

The mirror by which it was first shown measured nearly fifty inches across, and weighed 2,118 pounds. It was slung in a ring, and the sheet-iron tube in which it rested was thirty-nine and a-half feet long and four feet ten inches wide. Ladders fifty feet in length gave access to a movable stage, from which the observer communicated through speaking tubes with his assistants. The whole erection stood on a revolving platform; for the modern equatorial form of mount, by which the diurnal course of the heavens is automatically followed, was not then practically available, and the necessary movements had to be imparted by hand. This involved the attendance of two workmen, but was otherwise less inconvenient than might be supposed, owing to the skill with which the required mechanism was contrived.

Herschel estimated that, with a magnifying-power of 1,000, this grand instrument could, in the climate of England, be effectively used during no more than one hundred hours of every year. A review with it of the whole heavens would hence have occupied eight centuries. In point of fact, he found the opportunities for its employment scarce. The machine took some time to get started, while the twenty-foot was ready in ten minutes. The speculum, moreover, proved unpleasantly liable to become dewed in moist weather, or frozen up in cold; and, in spite of all imaginable care, it preserved the delicacy of its polish no more than two years. An economist of minutes, such as its maker, could, then, do no otherwise than let the giant telescope lie by unless its powers were expressly needed. They were surprisingly effective. “With the forty-foot instrument,” he reported to the Royal Society in 1800, “the appearance of Sirius announced itself at a great distance like the dawn of the morning, till this brilliant star at last entered the field, with all the splendour of the rising sun, and forced me to take my eye from that beautiful sight.” Which, however, left the vision impaired in delicacy for nigh upon half-an-hour.

Thus the results gathered from the realisation of Herschel’s crowning optical achievement fell vastly short of what his imagination had pictured. The promise of the telescope’s initial disclosures was not realised in its subsequent career. Yet it was a superb instrument. The discovery with it of Mimas gave certain proof that the figure of the speculum was as perfect as its dimensions were unusual. But its then inimitable definition probably fell off later. Its “broad bright eye” was, for the last time, turned towards the heavens January 19th, 1811, when the Orion nebula showed its silvery wings to considerable advantage. But incurable dimness had already set in—incurable, because the artist’s hand had no longer the strength needed to cure the growing malady. The big machine was, however, left standing, framework and all. It figured as a landmark on the Ordnance Survey Map of England; and, stamped in miniature on the seal of the Royal Astronomical Society, aptly serves to illustrate its motto, “Quicquid nitet notandum.” At last, on New Years Eve, 1839, the timbers of the scaffolding being dangerously decayed, it was, with due ceremony, dismounted. 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.

Herschel married, May 8th, 1788, Mary, the only child of Mr. James Baldwin, a merchant in the City of London, and widow of Mr. John Pitt. She was thirty-eight and he fifty. Her jointure relieved him from pecuniary care, and her sweetness of disposition secured his domestic happiness. They set up a curious double establishment, taking a house at Upton, while retaining that at Slough. Two maidservants were kept in each, and a footman maintained the communications. So at least runs Mrs. Papendick’s gossip. Miss Burney records in her Diary a tea at Mr. De Luc’s, where Dr. Herschel accompanied a pair of vocalists “very sweetly on the violin. His newly-married wife was with him, and his sister. His wife seems good-natured; she was rich, too! And astronomers are as able as other men to discern that gold can glitter as well as stars.”

He was now at the height of prosperity and renown. Diplomas innumerable were showered upon him by Academies and learned societies. In a letter to Benjamin Franklin, he returned thanks for his election as a member of the American Philosophical Society, and acquainted him with his recent detection of a pair of attendants on the “Georgian planet.” A similar acknowledgment was addressed to the Princess Daschkoff, Directress of the Petersburg Academy of Sciences. The King of Poland sent him his portrait; the Empress Catherine II. opened negotiations for the purchase of some of his specula, Lucien Bonaparte repaired to Slough incognito; Joseph Haydn snatched a day from the turmoil of his London engagements to visit the musician-astronomer, and gaze at his monster telescopes. By universal agreement, Dr. Burney declared, Herschel was “one of the most pleasing and well-bred natural characters of the day, as well as the greatest astronomer.” They had much in common, according to Dr. Burney’s daughter. Both possessed an uncommon “suavity of disposition”; both loved music; and Dr. Burney had a “passionate inclination for astronomy.” They became friends through the medium of Dr. Burney’s versified history of that science. In September, 1797, he called at Slough with the manuscript in his valise. “The good soul was at dinner,” he relates; and, to his surprise, since he was ignorant of Herschel’s marriage, the company included several ladies, besides “a little boy.” He was, nothing loth, compelled to stay over-night; discussed with his host the plan of his work, and read to him its eighth chapter. Herschel listened with interest, and modestly owned to having learnt much from what he had heard; but presently dismayed the author by confessing his “aversion to poetry,” which he had generally regarded as “an arrangement of fine words without any adherence to the truth.” He added, however, that “when truth and science were united to those fine words,” they no longer displeased him. The readings continued at intervals, alternately at Slough and Chelsea, to the immense gratification of the copious versifier, who occasionally allowed his pleasure to overflow in his correspondence.

“Well, but Herschel has been in town,” he wrote from Chelsea College, December 10th, 1798, “for short spurts and back again, two or three times, and I have had him here two whole days. I read to him the first five books without any one objection.” And again; “He came, and his good wife accompanied him, and I read four and a-half books; and on parting, still more humble than before, or still more amiable, he thanked me for the instruction and entertainment I had given him. What say you to that? Can anything be grander?”

In spite of his “aversion,” Herschel had once, and once only, wooed the coy muse himself. The first evening paper that appeared in England, May 3rd, 1788, contained some introductory quatrains by him. An excuse for this unwonted outburst may be found in the circumstance that the sheet in which they were printed bore the name of The Star. They began with the interrogation:

“What Star art thou, about to gleam

In Novelty’s bright hemisphere?”

and continued:

“A Planet wilt thou roll sublime,

Spreading like Mercury thy rays?

Or chronicle the lapse of Time,

Wrapped in a Comet’s threatening blaze?”

That they are of the schoolboy order need surprise no one. Such a mere sip at the “Pierian spring” could scarcely bring inspiration.

Herschel’s grand survey of the heavens closed with his fourth review. His telescopic studies thereupon became specialised. The sun, the planets and their satellites, the lately discovered asteroids, certain double stars, and an occasional comet, in turn received attention. Laboratory experiments were also carried on, and discussions of profound importance were laid before the Royal Society. All this cost him but little effort. The high tension of his earlier life was somewhat relaxed; he allowed himself intervals of rest, and indulged in social and musical recreations. Concerts were now frequently given at his house; and the face of beaming delight with which he presided over them is still traditionally remembered. Visits to Sir William Watson at Dawlish gave him opportunities, otherwise rare, for talks on metaphysical subjects; and he stayed with James Watt at Heathfield in 1810. He had been a witness on his side in an action for infringement of patent in 1793.

Herschel rented a house on Sion Hill, Bath, for some months of the year 1799; and from time to time stayed with friends in London, or sought change of air at Tunbridge Wells, Brighton, or Ramsgate. In July, 1801, he went to Paris with his wife and son, made acquaintance with Laplace, and had an interview with the First Consul. It was currently reported that Bonaparte had astonished him by the extent of his astronomical learning; but the contrary was the truth. He had tried to be impressive, but failed. Herschel gave an account of what passed to the poet Campbell, whom he met at Brighton in 1813.

“The First Consul,” he said, “did surprise me by his quickness and versatility on all subjects; but in science he seemed to know little more than any well-educated gentleman; and of astronomy much less, for instance, than our own king. His general air was something like affecting to know more than he did know.” Herschel’s election in 1802 as one of the eight foreign Associates of the French Institute was probably connected with his Parisian experiences.

He inspired Campbell with the most lively enthusiasm. “His simplicity,” he wrote, “his kindness, his anecdotes, his readiness to explain—and make perfectly conspicuous too—his own sublime conceptions of the universe, are indescribably charming. He is seventy-six, but fresh and stout; and there he sat, nearest the door at his friend’s house, alternately smiling at a joke, or contentedly sitting without share or notice in the conversation. Any train of conversation he follows implicitly; anything you ask, he labours with a sort of boyish earnestness to explain. Speaking of himself, he said, with a modesty of manner which quite overcame me, when taken together with the greatness of the assertion, ‘I have looked further into space than ever human being did before me; I have observed stars, of which the light, it can be proved, must take two millions of years to reach this earth.’ I really and unfeignedly felt at the moment as if I had been conversing with a supernatural intelligence. ‘Nay, more,’ said he, ‘if those distant bodies had ceased to exist two millions of years ago we should still see them, as the light would travel after the body was gone.’ These were Herschel’s words; and if you had heard him speak them, you would not think he was apt to tell more than the truth.”

The appearance of a bright comet, in October, 1806, drew much company to Slough. On the 4th, Miss Herschel narrates, “Two parties from the Castle came to see it, and during the whole month my brother had not an evening to himself. As he was then in the midst of polishing the forty-foot mirror, rest became absolutely necessary after a day spent in that most laborious work; and it has ever been my opinion that on the 14th of October his nerves received a shock from which he never got the better afterwards; for on that day he had hardly dismissed his troop of men when visitors assembled, and from the time it was dark, till past midnight, he was on the grass-plot surrounded by between fifty and sixty persons, without having had time to put on proper clothing, or for the least nourishment to pass his lips. Among the company I remember were the Duke of Sussex, Prince Galitzin, Lord Darnley, a number of officers, Admiral Boston, and some ladies.”

A dangerous attack of illness in the spring of 1807 left Herschel’s strength permanently impaired. But he travelled to Scotland in the summer of 1810, and received the freedom of the City of Glasgow. Then, in 1814, he made a final, but fruitless attempt, to renovate the four-foot speculum. In the midst of the confusion attending upon the process, word was given to prepare for the reception of the Czar Alexander, the Duchess of Oldenburg, and sundry other grandees just then collected at Windsor for the Ascot races. The setting to rights was no small job; “but we might have saved ourselves the trouble,” his sister remarks drily, “for they were sufficiently harassed with public sights and festivities.”

On April 5th, 1816, Herschel was created a Knight of the Royal Hanoverian Guelphic Order, and duly attended one of the Prince Regent’s levées in May. He went to town in 1819 to have his portrait painted by Artaud. The resulting fine likeness is in the possession of his grandson, Sir William James Herschel. The Astronomical Society chose him as its first President in 1821; and he contributed to the first volume of its memoirs a supplementary list of 145 double stars. The wonderful series of his communications to the Royal Society closed when he was in his eightieth year, with the presentation, June 11th, 1818, of a paper on the Relative Distances of Star-clusters. On June 1st, 1821, he inserted into the tube with thin and trembling hands the mirror of the twenty-foot telescope, and took his final look at the heavens. All his old instincts were still alive, only the bodily power to carry out their behests was gone. An unparalleled career of achievement left him unsatisfied with what he had done. Old age brought him no Sabbath rest, but only an enforced and wearisome cessation from activity. His inability to re-polish the four-foot speculum was the doom of his chef d’œuvre. He could not reconcile himself to it. His sunny spirits gave way. The old happy and buoyant temperament became overcast with despondency. His strong nerves were at last shattered.

On August 15th, 1822, Miss Herschel relates:—“I hastened to the spot where I was wont to find him with the newspaper I was to read to him. But I was informed my brother had been obliged to return to his room, whither I flew immediately. Lady Herschel and the housekeeper were with him, administering everything which could be thought of for supporting him. I found him much irritated at not being able to grant Mr. Bulman’sC request for some token of remembrance for his father. As soon as he saw me, I was sent to the library to fetch one of his last papers and a plate of the forty-foot telescope. But for the universe I could not have looked twice at what I had snatched from the shelf, and when he faintly asked if the breaking-up of the Milky Way was in it, I said ‘Yes,’ and he looked content. I cannot help remembering this circumstance; it was the last time I was sent to the library on such an occasion. That the anxious care for his papers and workrooms never ended but with his life, was proved by his whispered inquiries if they were locked, and the key safe.”

CThe grandson of one of Herschel’s earliest English friends.

He died ten days later, August 25th, 1822. Above his grave, in the church of Saint Laurence at Upton, the words are graven:—“Coelorum perrupit claustra”—He broke through the barriers of the skies.

William Herschel was endowed by nature with an almost faultless character. He had the fervour, without the irritability of genius; he was generous, genial, sincere; tolerant of ignorance; patient under the acute distress, to which his situation rendered him peculiarly liable, of unseasonable interruptions at critical moments: he was warm-hearted and open-handed. His change of country and condition, his absorption in science, the homage paid to him, never led him to forget the claims of kindred. Time and money were alike lavished in the relief of family necessities. He supported his brother Alexander after his retirement from the concert-stage in 1816, until his death at Hanover, March 15th, 1821. Dietrich’s recurring misfortunes met his unfailing pity and help. He bequeathed to him a sum of £2,000, and to his devoted sister, Caroline, an annuity of £100.

His correspondents, abroad and at home, were numerous; nor did he disdain to remove the perplexities of amateurs. In a letter, dated January 6th, 1794, we find him explaining to Mr. J. Miller of Lincoln’s Inn, “the circumstances which attend the motion of a race-horse upon a circle of longitude.” And he wrote shortly afterwards to Mr. Smith of Tewkesbury:—“You find fault with the principles of gravitation and projection because they will not account for the rotation of the planets upon their axes. You might certainly with as much reason find fault with your shoes because they will not likewise serve your hands as gloves. But, in my opinion, the projectile motion once admitted, sufficiently explains the rotatory motion; for it is hardly possible mechanically to impress the one without giving the other at the same time.”

On religious topics he was usually reticent; but a hint of the reverent spirit in which his researches were conducted may be gathered from a sentence in the same letter. “It is certainly,” he said, “a very laudable thing to receive instruction from the great workmaster of nature, and for that reason all experimental philosophy is instituted.”

To investigate was then, in his view, to “receive instruction”; and one of the secrets of his wonderful success lay in the docility with which he came to be taught.