Littell's Living Age/Volume 129/Issue 1670/Sir William and Caroline Herschel
From The Quarterly Review.
In the early part of the seventeenth century there was a great persecution of the Protestants in Moravia. Among those who fled from their homes during the evil days were three brothers named Herschel, who became possessed of land in Saxony, and settled there. One of the brothers established himself as a brewer at Pirna, near Dresden. Abraham Herschel, the son of the Pirna brewer, was landscape-gardener to the king, and obtained considerable reputation by his skill and taste in his profession. Isaac Herschel, Abraham's third and youngest son, was born in 1707. Declining to follow the profession of a gardener to which he was destined, the young man resolved to devote himself to music, and became a hautboy-player in the Hanoverian Royal Guard. At an early age Isaac married, and settled in Hanover, where he had a large family, two of which were William—afterwards the great astronomer, "whose name is so familiar to English ears—and Caroline, the subject of the present memoir.
The fame of Sir William Herschel as an astronomer is perhaps second only to that of Sir Isaac Newton; but few are aware how greatly he was indebted to his sister. For forty years, from the time when he first commenced his career of astronomical discovery until the grave closed over him, Caroline Herschel never quitted him. She was his trusted assistant; it was she who performed the vast and complicated numerical calculations that made his observations available to science; she was his amanuensis, and, till he married late in life, his housekeeper. It was she who converted his rough notes into lucid papers to be read before learned societies; she did for him an amount of labour which filled those who were in the secret with amazement; she served him with a great and unwearied love, content to stand aside and claim no share in the credit of all the great works he performed. It is hard to find a parallel to the entire self-abnegation with which she gave up all the energies of her mind and body to him.
The volume now before us brings the life of this very remarkable lady for the first time before the general reader. It is in many respects extremely entertaining; it is full of racy extracts from her letters and journals. We make acquaintance with a very original mind; we learn to admire a very warm-hearted woman, full of prejudices and oddities, but. with an absence of selfishness as charming as it is uncommon. But we cannot help regretting that the authoress did not extend her plan, and that the opportunity has been lost of making us better acquainted with Sir William Herschel. No life of that great astronomer has been written, and we should have been well pleased if the publication of the present memoir had been made the occasion of remedying the defect. It would have been easy for the authoress to satisfy the not ungraceful curiosity of the world respecting the life of her distinguished ancestor; but the memoir adds but little to our knowledge of him. Those who are acquainted with the scattered notices of his life may sometimes see, in a chance phrase of Miss Herschel, the correction of a mistake, or a hint which may make clear some hitherto doubtful point; and to those who know Sir William Herschel's work the present volume is like a personal introduction to the workman. But the general reader cannot fairly be expected to possess this knowledge. Nowhere throughout the book are we told the meaning of the astronomical activity in which the brother and sister passed their lives. We cannot be expected to care much about mere hard work apart from sympathy with its object; and even intellectual toil is uninteresting unless we are allowed to share the hopes and fears of the labourers. We hear of Sir William Herschel grinding for sixteen hours at a stretch at one of his telescope mirrors, and of Miss Herschel reading to him as he works, and putting food into his mouth by bits, while he continues his monotonous labour without removing his hands; but the anecdote is unmeaning unless we know why he toiled so hard: a railway signal-man sometimes works even longer without creating any public enthusiasm. The real interest of the incident lies in this: that Sir William Herschel had conceived the idea of a new form of telescope, and was labouring with almost frenzied energy to put it into execution, that the plan succeeded so well as to revolutionize all previous methods of making reflecting telescopes, and laid the foundations of modern stellar astronomy. This is the kernel; the memoir gives us but the shell. Again, throughout the book we have not a hint as to the boundary of Herschel's peculiar province in astronomy; in what condition he found the science; wherein he improved it; what object he proposed to himself; and how far that object was attained. It seems to us that the life of his faithful assistant, who shared all his labours and all his hopes, cannot be intelligently told without at the same time telling us this. We may be made to admire the energetic woman; but Miss Herschel would have felt anything but pleased if any one had admired in her the woman, at the expense of the astronomer.
The authoress sometimes does less than justice to the gifted lady who is the subject of her book. During her life, as her brother's assistant, he was, of course, commanding officer; his was the invention, the genius, the rapid intuition, and, most properly, the lion's share of fame. To her lot fell the duty of patient attention; hers was the labour of calculation; the arrangement and transcription of rough notes. Mathematical analysis belonged to him; arithmetical computations were handed over to her. But to carry out his instructions and to perform the tasks assigned to her required a large range of knowledge, as well as indomitable perseverance. It is therefore not fair to the memory of Miss Herschel to make it appear that she was profoundly ignorant of even rudimentary mathematics. To give an instance: an extract is given in the memoir, under the date 1786, from a MS. book belonging to Miss Herschel, and sent by her from Hanover to Sir John Herschel after his father's death. The authoress says, " The information is of a very miscellaneous kind, but matters connected with her special study form the greater part of the questions" which, as we are elsewhere told, Miss Herschel used to put to her brother when they met at breakfast before separating for their daily task. We are then favoured with three or four interrogatories, which the writer of the memoir may, perhaps, consider likely to elicit "information of a miscellaneous kind," but which Miss Herschel in 1786 would have looked upon as absolutely childish. E.g., "Given the true time of the transit, take a transit? . . . Of a logarithm given, to find the angle?"
Now, in 1786 Miss Herschel had been fourteen years her brother's assistant. On the very same page where this absurd extract is given, there is an entry in Miss Herschel's journal: —
4th. I calculated nebulæ all day, etc. . . .
9th. Calculated the places of one hundred nebulæ.
The lady who could make the two latter entries as records of her ordinary daily life would be little likely to ask for information as to the mode of taking a transit, or the way of finding an angle from its logarithm. It is obvious that the questions belong to the days when Miss Herschel first joined her brother at Bath, in 1772, when she was ignorant of almost everything except reading and writing. The memoir would be of little interest if it were not a record of difficulties overcome with immense rapidity by a very powerful mind. It is quite unfair to represent the Miss Herschel of 1786, who had already herself discovered a comet unassisted, and corresponded on equal terms with the leading astronomers of Europe, as asking childish questions of her brother. The questions are not worth noting at all; but if they are noted, they ought to be relegated to the first chapter as evidence of Miss Herschel's sincerity when she complained that she arrived in England absolutely ignorant of everything likely to be of use to her in the life that lay before her.
It is strange that we must go to a French philosopher for the record we possess of one of the most original thinkers who has appeared in this country. Except a few obituary notices in various periodicals, no biography of Sir William Herschel exists, except the short one by M. Arago prefixed to this paper, and in this case the whole is comprised within a dozen pages of the little volume in which it appeared, and these are mostly devoted to an analysis of his work.
We propose to give such particulars respecting Sir William Herschel's life as may serve to appreciate the new light thrown upon his character by the journals and letters of his sister. But it is evident that the authoress of the memoir has materials at her disposal much more ample than any to which persons beyond her family circle can have access; and we cannot but wish that she had herself performed the task. If the present volume were at some future time remodelled, so as to include the life of Sir William Herschel as well as that of his sister, it would fill a blank much felt by those interested in the history of astronomy. Although it is acknowledged that Sir William Herschel occupies the second place among English astronomers, it is not likely that he will become the subject of a separate biography. We think this, partly from the nature of his work, and partly from the character of his life. He wrote nothing but papers for learned societies, and his communications to learned societies were hardly more than transcripts of entries in the inexhaustible observation-book at Slough. The work he produced was new, but, from its very novelty, imperfect. Sir William Herschel was obliged to invent the instruments and fashion the materials he used. His object was more to traverse a large field of observation than to strive after minute details. He knew that his inventions would be improved upon, and the imperfections of his work be corrected, but he had taken possession of a domain in science opened out by himself, and full of wonders absolutely new; he was eager to push his daring investigations deeper and yet deeper in the abyss whose marvels had never been seen by the eye of any mortal man till they were unveiled to him. To linger on such a road longer than was absolutely necessary would have been for him waste of time; to dwell on trifles would have been but labour lost; and he was too good a mechanic to force effort beyond the point at which it ceased to be effectual. 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. He attained a degree of precision to which the elder astronomer laid no claim. The contrast between the father and son was such as might have been anticipated from their training. The father, untrained, or, rather, self-trained in mathematics, invented methods and pursued science as the passion of his life; but until he reached middle age his devotion to astronomy was indulged at the expense of his regular avocations, and as a relief from regular business. If one may venture to speak of such a consummate observer as a rough-and-ready astronomer, the expression is only used as contrasting him with his son. Sir John, "born under the shadow of the forty-foot telescope," was trained for an astronomer from his earliest youth. By rare good fortune, the gifts of nature enabled him to avail himself of the opportunities to which he was born. Senior wrangler of his year—a year in which the great calculator Babbage went out without even competing for the first place, Sir John developed into the first mathematician of his day. His father had learnt mathematics that he might understand astronomy; the son was carefully trained to them from a boy, and passed a long life polishing the delicate weapons which had been put into his hands. No wonder that, revising Sir William Herschel's calculations, he should have superseded his father's labours, but without diminishing his father's fame. Another reason is that Sir William Herschel's writings, spread over more than forty years, are all disconnected—they are the mere transcript of the work on which he was for the moment occupied. They have never been collected, but remain scattered over more than forty volumes of the "Philosophical Transactions." His life affords but few incidents for the biographer. From the time when he first gave himself up to astronomy until his death, he hardly ever absented himself for more than a few days from his telescopes. The record of his life is the record of his work. Apart from the result of his scientific inquiries, the most industrious biographer would not be able to put together the materials for a moderate-sized volume. How much the greater, then, is the regret that the present opportunity has been allowed to escape!
Though M. Arago's analysis of Herschel's labours is short, it is most valuable, and it is pleasant to find ourselves under such good guidance. As a biographer we follow him with distrust; for, to say the truth, M. Arago exhibits that recklessness of foreign geography and nomenclature which even highly-educated Frenchmen sometimes permit themselves to indulge. His first page contains two random shots of this kind: he says "Abraham Herschel . . . demeurait à Mähren, d'où il fut expulsé" etc., apparently unaware that Mähren is not a town, but the German name for Moravia. Moreover, it was not Abraham Herschel, but Hans, his father, who was driven from his home.
We should not have thought it worth while to criticise M. Arago's geography, or the genealogy which he gives of the Herschel family, were it not that others have followed him in the further mistake of asserting that Jacob Herschel was the father of William and Caroline. Jacob Herschel was an elder brother of Sir William, and at the time of the latter's birth in 1738 was a child of four years old.
The family of whom William and Caroline Herschel were members all showed remarkable talent at an early age. Their father was an excellent musician, and he trained all his children to follow his own profession. Each of them, when they attained the age of two years, went to the Hanoverian garrison school, and there William soon outstripped his brothers, and at last caused the schoolmaster to acknowledge that the boy had got beyond him. By the time he was fourteen William was a good performer on the oboe and the violin, and had learned all the schoolmaster could teach of French and mathematics. Caroline never had much schooling. Her mother considered learning unnecessary for a woman, and preferred to keep her daughter closely employed in household work to allowing her time for mental cultivation. The consequence of this prejudice was that she grew up almost to womanhood without possessing more than the merest rudiments of knowledge. She could read and write, but that was all. It was not till many years afterwards, when she was with her brother William in England, that she began to learn arithmetic. This brings into still stronger relief the native shrewdness which enabled Miss Herschel to pick up, in the midst of other avocations, accomplishments such as distinguished her later life.
For many years before Caroline Herschel's birth, her father's constitution had been impaired by the hardships of war. After the battle of Dettingen, where King George II. of England, at the head of an army of English, Hanoverians, and Hessians, drove the French, under De Noailles, across the Main, the unfortunate bandmaster of the Royal Guard lay all night in a wet furrow, and in consequence contracted an asthmatic affection which embittered the whole remainder of his life. But he still remained in the army. Among the earliest of Caroline Herschel's recollections is the sight of the confirmation of her brother William, on which occasion he wore "his new Oboësten uniform," for he as well as his elder brother Jacob had joined their father as musicians in the band of the Guard. They were, indeed, a family of musicians, for the elder daughter married another bandsman in the same regiment, named Griesbach. Miss Herschel records that her father never much approved of the match, for the somewhat quaint reason that Griesbach was but an indifferent musician.
Alexander Herschel, the eldest of the sons, was, though not a soldier, a most accomplished musician: indeed, when William and Caroline deserted music for astronomy in later years, Alexander still adhered to his first profession, though he had a large share of his distinguished brother's mechanical ingenuity, and became an efficient maker of mathematical and optical instruments for his observatory.
When Caroline was about five years old the home in Hanover was broken up, and, as events turned out, it was never afterwards entirely reunited. The Guard was ordered to England, and Isaac Herschel, with his two sons and his son-in-law, accompanied it. Mrs. Herschel kept house as well as she could, with much straitened means; but the family circumstances were not improved by the arrival of Mrs. Griesbach, the married daughter, whose husband marched with the rest, but forgot to leave any part of his pay for the support of his wife.
Even at that time the characteristic genius of William Herschel had begun to show itself. His talk was of the discoveries and theories of Newton, Leibnitz, and Euler; his recreation the invention and fashioning of scientific instruments, in which he was assisted by his brother Alexander. After a year's absence the regiment returned, and it is recorded that William's sole purchase brought from England was a copy of Locke on the "Human Understanding." Jacob, his brother, a much less amiable character, who seems always to have been regarded with feelings akin to terror in the Herschel household, threw up his appointment in the band, in consequence of a slight which he considered himself to have suffered, by the appointment of another musician to a post he coveted. He appeared in Hanover in smart English clothes to set his mother's household by the ears, while his father and brother accompanied their regiment on its homeward march.
William Herschel was the next to leave the band of the Guard, and, however sincerely we may rejoice at an event which left that great man free to become an astronomer and an Englishman, it must be confessed that he did not stand on the order of his going, or waste his time in preliminaries. At the outbreak of hostilities in 1756 the Guard was of course engaged, and the bandmaster, with his son William, marched among the rest. The Guard was attached to the ill-starred force under the Duke of Cumberland, when Marshal d'Estrées was directed, with sixty thousand Frenchmen, first against the Prussian dominions lying on the Rhine, and next against Hanover itself: the British and Hanoverian army, ill-led and outmatched, was at last subjected by D'Estrées to a disastrous defeat at Hartenbeck, on the Weser. The battle took place within twenty miles of Hanover, so that the sufferings of the Hanoverian army were brought almost under the very eyes of their friends. William Herschel, who was always of a delicate frame, suffered so much in health, that, as Miss Herschel says in a memoir written many years after, "his parents resolved to remove him."
The "removal" of a soldier in wartime, without the consent previously obtained of his superiors, is naturally attended with difficulty. Miss Herschel thus tells the story:—
I had only by chance a passing glimpse of my brother as I was sitting at the entrance of our street door when he glided like a shadow along, wrapt in a great coat, followed by my mother with a parcel containing his accoutrements; after he had succeeded in passing unnoticed beyond the last sentinel at Herrenhausen, he changed his dress. My brother's keeping himself so carefully from all notice was undoubtedly to avoid the dangers of being pressed, for all unengaged young men were forced into the service.
As William Herschel was already a soldier, one cannot avoid the suspicion that the danger incurred by his "strategic movement" was not that of being pressed.
William Herschel made his way safely to England, and from that time forth we may claim him as an Englishman. He never again left his adopted country for more than a passing visit.
After his departure evil days fell upon Hanover. The Duke of Cumberland concluded with Richelieu the ignominious Convention of Closterseven, by which thirty-eight thousand Hanoverians laid down their arms and were dispersed. The duke was deprived of all his military commands, but that did not alter the humiliating terms of the treaty. No stipulations were made for the protection of the electorate, and Hanover was therefore plundered without mercy, and laid under enormous contributions. Caroline Herschel was then only about seven years old, but she entertained a lively recollection of the miseries endured by the Hanoverians in that time of national calamity. Sixteen private soldiers of the victorious army were quartered in Mrs. Herschel's house, besides some officers, who took possession of the best apartments. Caroline's time was occupied by attendance at the garrison school, and in learning knitting. The first stocking she made for her brother Alexander reached, she tells us, to her chin when she was finishing the upper rows; and to the end of her life she was always small in stature. Eighty years later, when she was a celebrity, and had come back to her native Hanover to die, she was familiarly known as "the little old lady;" and in letters written in extreme old age she often records how much she was touched by the respect shown to her on the occasions of her visits to the theatre, which she attended almost to the last, and where her diminutive stature made her a noticeable, as well as a familiar figure.
Miss Herschel's biographer does not tell us what became of William Herschel after his escape to England. M. Arago says that he was engaged by Lord Durham, as master of the band in an English regiment, then quartered on the borders of Scotland. The Gentleman's Magazine,[2] probably with greater accuracy, states that, after struggling with great difficulties in London, he was engaged by the Earl of Darlington, to superintend and instruct a military band then forming by that nobleman in the county of Durham, and the opening thus afforded contributed so far to increase his reputation and connections, as to induce him to spend several years in the neighbourhood of Leeds, Doncaster, and Pontefract, where he had many pupils, and conducted public concerts and oratorios. Of this part of his life little is known; but in 1765, eight years after he had taken his hurried leave of Hanover, he was elected organist of the parish church at Halifax. A story is told of this election which bears an air of truth, and is likely enough, from the character of the man. One Joah Bates, a gentleman, well known to collectors of musical and literary anecdotes, was with a friend in the nave of the church at Halifax, when they were addressed by Herschel, at that time entirely unknown to them. He told them that he was a musician—that he desired to become the parish organist, but that he had never had an opportunity of playing on the organ. He added that his musical acquirements were considerable, and that if he were allowed the opportunity of practice, he could certainly learn to play before the day of the election. The story goes on to say that the friends were so struck with the young Hanoverian's modest self-confidence, that they gave him the opportunity he desired, and became his warm supporters. Be that as it may, he won the election; and the emoluments of the office at once put him beyond the reach of want, and gave him that leisure for self-cultivation which was such an object to his energetic mind. He plunged into mathematics with characteristic impetuosity, and at the same time found time for the study of Italian, Latin, and Greek. At first his mathematical studies were directed principally to the theory of harmonics; his principal assistant in that study being, according to Arago, a learned but very obscure mathematical work on the "Theory of Music," by Robert Smith. It was music, says Arago, which first led him to mathematics, and mathematics which made him famous.[3] Robert Smith, successor to Cotes in the chair of natural philosophy at Cambridge, was the author of "A Complete System of Optics," which afterwards became one of William Herschel's inseparable companions. "He used to retire to bed, with a basin of milk or glass of water, and Smith's "Harmonics and Optics," or Fergusson's "Astronomy," as his companions, and go to sleep buried under his favourite authors. His first thoughts on rising were to obtain instruments for viewing those objects of which he had been reading."[4] In the course of the year following William Herschel's appointment at Halifax, he obtained the more lucrative post of organist in the Octagon Chapel at Bath.
The parent nest in Hanover now rapidly emptied. Jacob, the eldest brother, followed William to England, and became first violin in the court orchestra—Alexander and Dietrich were the only two, with the exception of Caroline, who remained at home. Alexander obtained the somewhat mysterious post of Stadtmusicus of Hanover, his duties consisted in "blowing a corale from the Markt Thurm, and giving a daily lesson to an apprentice." The father of the family left the army in 1760, and settled down in the acknowledged position of the principal musical professor of the capital. He used to give concerts, in which his pupils performed, and even his little daughter, and his still smaller son, Dietrich, took part with their violins.
As time went on, Caroline became too useful as a household drudge to be allowed to participate much in the education which Isaac Herschel was eager to give to his sons. Her mother avowed the distinct opinion that book-lore was unfitted for a woman. For years, as she grew up to womanhood, her mind remained in a state of stagnation. She used bitterly to complain—and it is the only subject on which, in her memoirs, she shows any bitterness—that her mother's prejudices prevented her from acquiring knowledge that would have made her more useful in after-years to her brother William. Her parents never agreed on the subject. Her father wished to give her something like a polished education; her mother was determined that she should have a rough one.
When Caroline Herschel was about seventeen, her father died. For some time before that event, he had lost the use of his right side by a paralytic seizure, and although he continued to receive pupils at his house, he did not regain his former skill on the violin. He was reduced at last principally to the occupation of copying music, and the family resources naturally fell to a very low ebb. The death of her father deprived Caroline of the last friend who sympathized with her desire for better instruction. Her mother looked upon her as a servant; and her brother Jacob, who could have helped her, treated her with a lofty insolence for which the reader of Miss Herschel's recollections heartily dislikes him. She at length obtained permission to learn millinery and dress-making, as the only means of avoiding the apparently not improbable contingency of "being turned into an abigail or a housemaid."
In the house of Madame Küster, where, according to the custom of the day, several young ladies of good family were learning the art of dress-making, she was fortunate enough to make an acquaintance, who proved the most valued friend of her after-years.
One of the young women [she writes] after a lapse of thirty-five years, when I was introduced to her at the queen's lodge, received me as an old acquaintance, though I could but just remember having sometimes exchanged a nod and smile with a sweet little girl about ten or eleven years old.
The lady whom she records as having recognized her when a member of the queen's household, had then become Madame Beckedorff, who remained her fast friend until Madame Beckedorff's death. When Miss Herschel herself died, years later, it was the daughter of this kind friend who closed her eyes.
But the darkest night comes to an end: an event occurred which changed altogether the current of Miss Herschel's life. Her brother William had, as we mentioned above, removed to Bath, where he rapidly became known and respected. His duties as organist at the Octagon Chapel did not occupy all his time; he used to compose anthems, chants, and sometimes whole services for the choir under his management. But so rapid and methodical a worker found that when all was done he had still abundant leisure. On the retirement of Mr. Lindley from the management of the public concerts, Herschel added this to his other avocations, and was consequently immersed in business of the most laborious kind during the Bath season. It occurred to him that Caroline Herschel might come over to England and keep house for him. It was also possible that she might be made available as an assistant to him in his concerts. Music came almost by nature to every member of his family; he probably thought that it would be easy for his sister to acquire the necessary amount of knowledge, and the result showed how accurately he judged her. We may reasonably suppose that, living as she had done from infancy with musicians, and accustomed almost as soon as she could speak to make herself useful at her father's concerts, she really knew a good deal about music, though the amount of her knowledge seemed quite insignificant to the scientific artists among whom her lot was cast. To no one did her acquirements appear more trifling than to herself. But her brother William was the only member of her family who really cared for her, and she repaid his rather patronizing affection with passionate devotion. The prospect of going to join her brother was like a peep into heaven to the poor little girl with her keen intellect and quick perception. She must have felt the consciousness of great talents thrown away, and she had acquired ample experience of the bitterness of high aspirations jeered at or disregarded. No wonder then if she eagerly grasped at the prospect of release held out by her brother's offer. Miss Herschel's disappointment was proportionately great when her crossgrained brother Jacob, who was at that time in Hanover, first refused to give his aid as a musical instructor, and at last turned the whole scheme into ridicule, and positively refused his consent to her leaving home; a refusal which, as head of the family, he was able to enforce.
Here for the first time the indomitable will, which afterwards became so marked a feature in Caroline Herschel's character, asserted itself. She could not obtain consent to her departure, but, at any rate, she could prepare for it: she records her determination with charming simplicity:—
Jacob [she writes] began to turn the whole scheme into ridicule, and of course he never heard the sound of my voice except in speaking, and I was left in the harassing uncertainty whether I was to go or not. I resolved at last to prepare, as far as lay in my power, for both cases, by taking in the first place every opportunity, when all were from home, to imitate with a gag between my teeth the solo parts of concertos, shake and all, such as I had heard them play on the violin; in consequence, I had gained a tolerable execution before I knew how to sing.
The journey to England was at last settled, much to her mother's disgust. But, as she says with great naiveté "Her anguish at my leaving was somewhat alleviated by my brother settling a small annuity upon her, by which she would be enabled to keep an attendant to supply my place." The last objection being now removed, she left Hanover in August, 1772. She went "from Helvot to Harrige"—more accurate geographers might, perhaps, have written from Hellevoetsluis to Harwich; but, indeed, Miss Herschel's idea of orthography remained abnormal to the end of her life. The authoress of the memoirs tells us that she has modernized the spelling throughout; we are not quite sure that we approve of the change. We are once or twice allowed to catch a glimpse of her without her modern disguise; for in one of her letters, written when she heard the news of Sir John Herschel's intended departure for the Cape in 1822, she exclaims, "Ja! if I was thirty or forty years junger, and could go too? in Gottes nahmen!" We quite agree with the authoress of the memoir that an old lady who had discovered eight comets might be allowed to spell in her own way; but we by no means subscribe to the conclusion that the trimming and modernising of her letters and memoranda have improved them.
Immediately on her arrival in Bath, Miss Herschel commenced her training. She knew no English, and, as she was to do the housekeeping and marketing, it was necessary at once to devote her attention to its acquisition. She also records that, on the first morning after her arrival, her brother began to teach her the rudiments of arithmetic. When we remember that it was principally as a calculator that she was afterwards remarkable, and that the numerical results which rendered her brother's observations available to science were all worked out by her, some idea is obtained of the keenness and perseverance which could so overcome the deficiencies left by early neglect. All difficulties vanished before her as if by magic. The immediate business on hand was the organization of William Herschel's concerts. Caroline's voice was tried, and was found satisfactory. She was set to work with three lessons a day, either singing or at the harpsichord. In a short time she was installed as the leading solo singer of the concerts and oratorios, which her brother provided for his fastidious audience. It then devolved upon her to train and lead the treble singers, and to copy the scores for the various performers.
For ten years the Herschels remained at Bath. William Herschel was indefatigable in his music-lessons, giving sometimes as many as thirty-eight in a day; but every spare moment was dedicated to studies, which more and more engrossed his attention, and at last compelled him to devote himself to the observation of the heavens. He became a member of a philosophical society in Bath, to which he contributed for several years papers on scientific subjects. It was thus at the very turning-point of his career that Caroline Herschel became the companion and fellow-worker of her brother.
In a shop in Bath William Herschel one day found a two-and-a-half-feet Gregorian telescope for hire. He became possessed of it, and took it into constant use, not only for observing the heavens, but for making experiments on its construction. He soon determined not to remain content with viewing what had been seen by others. He would enter on a course of original investigation for himself.
He wrote to inquire the price of a reflecting mirror for (I believe) a five or six foot telescope. The answer was that there were none of so large a size, but a person offered to make one at a price much above what my brother thought to give. About this time he bought of a Quaker resident in Bath, who had formerly made attempts at polishing mirrors, all his rubbish of patterns, tools, hones, polishers, unfinished mirrors, etc.; but all for small Gregorians, and none above two or three inches in diameter.[5]
This disappointment, which would, perhaps, have damped the ardour of a less enthusiastic man, proved an immense advantage to science. As his modest salary as organist would not enable him to buy a telescope, Herschel proceeded to make one. At first his telescope was to be moderate in size, and the plan was adopted only because it would be cheaper to make a large telescope than to buy one. But as he studied the subject his ambition increased. Expedients occurred to him for avoiding certain difficulties, mechanical and optical, which had hitherto prevented large reflecting telescopes from being used; and as the range of his knowledge of optics extended, he began to grasp the possibility of improvements in telescopes which should confer on them powers beyond the wildest dreams of former astronomers.
In Miss Herschel's memoir, as in all books dealing with astronomers and their doings, we hear constantly of Gregorian telescopes, Newtonian telescopes, Galilean telescopes. In works of later date we read of Herschelian telescopes; but naturally in works written for professed astronomers no one ever thinks it worth while to say in what the peculiarities of these instruments consist. It may therefore be mentioned here that all telescopes are modifications of two great types: refracting and reflecting. Refracting telescopes consist of a double convex lens, called the object-glass, to enlarge the object viewed, and a smaller double concave lens, or eye-piece, which is used as a microscope to examine the image formed by the object-glass. The common opera-glass is a telescope of this description. It is called after Galileo, the Florentine astronomer. Galileo is said to have received some casual information on the subject from a German whom he met at Genoa in 1609. He was able, after some experiments, to make a telescope which magnified no less than three times! He subsequently made one magnifying thirty-two times. The telescopes used by Huygens and Cassini did not exceed at their highest power one hundred and fifty times. Auzont, who constructed a telescope of three hundred feet focal length, to obviate chromatic aberration (a difficulty on which we do not propose to dwell, as in Herschel's time it had been substantially overcome), applied to his huge and unwieldy instrument a magnifying power of six hundred times.[6]
Reflecting telescopes consist of a concave mirror presented to the object viewed. In the focus of the curve formed by this mirror, and consequently in the spot where all the rays reflected by the mirror converge to a point, a smaller mirror is fixed, facing the first; and the image of the object looked at, after being magnified by the first mirror and concentrated on the small one, is examined by a lens or microscope in the same way that the eye-piece of the Galilean telescope examines the enlarged image made by the object-glass. It must be remembered that the focus, or focal point of a concave mirror, is the centre of the curve presented by such mirror. To make this clear, let us recur to first principles. A sphere is generated by the revolution of a circle round its axis; we may see it by spinning a half-crown on the table. Suppose, then, a circle of three inches radius so rotated, the result would be a sphere of six inches in diameter. If that sphere were formed of glass, and you cut out from any part of it a circular disc with a radius of one inch, you would have a concave glass, like a watch-glass, which would be described as being of two inches diameter, and three inches focal length.
We have said that the small mirror is placed in the focus of the curve of the large mirror, we did so to avoid distracting attention from the principle on which it is constructed; but the peculiarity of the Gregorian[7] telescope is that the small mirror is concave, and is fixed beyond the focal point of the larger reflector; while in the instrument invented by Cassegrain,[8] and called after him, the small mirror is convex, and is placed within the focal distance.
In both these instruments the reflector is perforated in the centre by a circular aperture, to allow of the insertion of a magnifying eye-piece.
Sir Isaac Newton, in 1669, hit upon the expedient of placing the small mirror at an angle to the large one. He was therefore able to dispense with the perforation of the large mirror, by reflecting the image on to a lens situated in the side of the tube of the telescope. Of course, in all these instruments, the small mirror and its attachments, placed in the tube between the reflector and the heavens, obscured a great deal of the light that would otherwise fall directly on the reflector. How to get rid of this inconvenience was the first problem presented to the mind of Herschel. The second was how to grind mirrors of such shape and size as to allow the application of magnifying powers enormously greater than any which had hitherto been considered possible. He succeeded in both attempts. The first difficulty was surmounted in a manner so simple that one is astonished it should have eluded the great inventors who preceded him. It occurred to him that if, instead of placing his reflector at right angles to the axis of his telescope, he inclined it a little forward, the image would be focused at a point on the edge of the tube, he could then dispense altogether with the second mirror and with the aperture in the reflector, and direct his eyepiece directly on the principal mirror itself. It was a case of Columbus and his egg over again.
Sir William summoned his brother Alexander from Hanover, and after Easter, when the termination of the Bath season left them a little leisure, they began to construct a telescope eighteen or twenty feet long! Every room was turned into a workshop. In the drawing-room worked a cabinet-maker, constructing tubes and stands for telescopes; in another room a huge turning-machine was erected, which Alexander picked up in Bristol.
Every leisure moment was eagerly snatched at for resuming some work which was in progress, without taking time for changing dress. Miss Herschel complains that they were continually tearing their lace ruffles, or bespattering them with molten pitch. On the grass-plot behind the house preparations were made for erecting the twenty-feet telescope, the precursor of that giant instrument which was afterwards the glory of Slough. The grinding of specula used formerly to be performed by hand, no machinery being sufficiently exact. The tool on which they were shaped was turned into the required form, and covered with coarse emery and water; the specula were then ground on it to the necessary figure, and afterwards polished with putty, or oxide of tin. To grind a speculum six or eight inches in diameter was considered a work of great labour;[9] what then must have been the difficulties incurred by the Herschels, who undertook to grind specula four feet in diameter? Miss Herschel was constantly in attendance on her brother while the grinding was going on.[10] She used to read to him while he was engaged in polishing. The authors selected were generally the "Arabian Nights," or the novels of Sterne and Fielding. She, however, managed to spare time for "two lessons a week" from Miss Fleming, the celebrated dancing-mistress, "to drill me for a gentlewoman; God knows how she succeeded!" In the midst of these multifarious occupations she mentions having copied the scores of "The Messiah" and "Judas Maccabeus" into parts for an orchestra of nearly one hundred performers, and the vocal parts of "Samson," besides instructing the treble singers, of whom she was now herself the first. William and Alexander Herschel used to throw themselves into their work with a glee like that of schoolboys out for a holiday. One Saturday night the brothers returned about twelve o'clock from a concert, pleasing themselves all the way with the idea that they would be at liberty to spend the next day, except a few hours' attendance at chapel, altogether at the turning-bench. Not liking to scandalize the good people of Bath by grinding their tools on Sunday, they ran out with a lantern to their landlord's grindstone, and set to work on their delicate task in semi-obscurity. They would probably have worked till daylight, but William was brought back fainting with the loss of one of his finger-nails. We ought, perhaps, to apologize for dwelling on these trifling details. Our excuse is that they make us know a great man better.
Pending the completion of the great telescope, the brothers manufactured several of smaller dimensions. Sir William had one of five, and one of seven feet focal length.
On the evening of the 13th of March, 1781, Herschel was engaged in examining some small stars in the vicinity of the constellation Gemini, when his attention was attracted to one more than the rest. He applied to his telescope higher magnifying powers, and found, to his surprise, that the apparent diameter of the body increased considerably. It was not, then, a fixed star, for no magnifying power presents one of those distant luminaries as other than a point of light. Careful examination showed that it was moving at the rate of two and a half seconds per hour. It was the planet now called Uranus. Herschel had commenced his career by a discovery which raised him to the front rank of astronomers. Continental observers wished to confer on the new planet the name of its discoverer, and the symbol by which it is known in astronomy, still bears his initial. But after an interval, during which it was called by Herschel's proposed name of the "Georgium Sidus," it was christened "Uranus"—now its recognized appellation. Uranus had often been seen before; indeed, it was observed and recorded on no less than twenty previous occasions as a fixed star. Arago[11] points out that "if Herschel had directed his telescope to the constellation Gemini eleven days earlier (that is, on March 2 instead of March 13) the proper motion of Uranus would have escaped his observation, for on the 2nd the planet was in one of its stationary points. It will be seen from this remark on what may depend the greatest discoveries in astronomy." One step in this fascinating science inevitably leads to another. Perturbations in the course of Uranus led Adams, in England, and Leverrier, in France, to suspect the existence of yet another planet, whose attraction should be sufficiently powerful to alter the path of Uranus through space, and yet so distant as to have eluded observers since the beginning of the world. The event proved that they were right, and Neptune was discovered by the Prussian astronomer Dr. Galle in the very spot indicated by the two great astronomers; who thus achieved probably the greatest triumph ever won by mathematical science.[12]
The fame of Herschel's discovery spread rapidly. The most prominent astronomers made the journey to Bath—no ordinary undertaking in those days—to see the great telescopes at which he was labouring with extraordinary assiduity[13] and to converse with their inventor. Miss Herschel's journals are filled with accounts of preparations for new oratorios and the making of new telescopes in almost equal proportions. The casting of a mirror for one of the instruments well-nigh proved fatal to all the adventurers. The metal was in the furnace, which unfortunately began to leak at the moment when ready for pouring. "Both my brothers," says Miss Herschel, "and the caster with his men, were obliged to run out at opposite doors, for the stone flooring flew about in all directions as high as the ceiling. My poor brother fell exhausted with heat and exertion on a heap of brickbats." A second casting resulted in a very perfect metal. While he was thus busily engaged, the king invited him to Windsor, and desired him to bring his instruments with him.
After this visit, Herschel never returned permanently to Bath; he was caressed and honoured by all the savants of the metropolis, and the king was so interested by the extraordinary objects in the starry heavens which were shown to him, that he invited the Bath musician to become his private astronomer, with a salary of 200l. per annum. In such notices of Sir William Herschel's life as have been published, it has been assumed that the king provided for his astronomer with royal munificence, M. Arago adopts the current story. Such, however, was not the case. The income of Sir William Herschel at Bath, from his organist's salary and his musical pupils, very greatly exceeded that which he accepted at the hands of his royal patron. Miss Herschel speaks, in one of her latest letters[14] of the life of privations and struggles undergone by her brother—she says nothing of her own—during between twenty and thirty years, till he had realized a sufficient capital for living respectably by the making of seven, ten, twenty, and twenty-five feet telescopes. She also mentions that it was at first intended, when M. de Mainborg, who had formerly been one of the king's tutors, and was afterwards his private astronomer, died, to make Sir William Herschel astronomer at Kew in his room. But it was otherwise determined, for "the king was surrounded by some wiseacres who knew how to bargain, and even offered 100l if he would go to Hanover."
A house was taken at Datchet, in which Miss Herschel was promptly installed as housekeeper and general assistant. The new home was a large neglected place, ruinous, and overgrown with weeds. Miss Herschel's economical soul was appalled at the price of everything, from coals to butcher's meat; but there were stables where mirrors could be ground; a laundry which would serve for a library, and a grass-plot where the twenty-feet telescope was to be erected. The brother and sister agreed that now they were really in the country they could live on eggs and bacon for next to nothing. Miss Herschel found that she was to be trained for an assistant astronomer, and, "by way of encouragement," as she says, a telescope, adapted for sweeping, was given to her. "I was to sweep for comets, and I see by my journal that I began August, 1782, to record all the remarkable appearances that I saw in my sweeps." She soon had the satisfaction of seeing that her brother was satisfied with her endeavours to assist. It was her business to watch the clock, and note the times of various phenomena; to write down memoranda; to fetch and carry instruments, or to measure the ground with poles. Something of this kind occurred every moment. Measurements on the diameter of the newly-discovered Georgium Sidus, and observations of other planets, double stars, etc., were made with great assiduity. From this time, and for many years, almost the whole of almost every night that was not too cloudy was devoted to observation of the heavens, until daylight sent the astronomers to their beds. But it was soon found that Caroline Herschel must become entirely attached to the writing-desk, so that she seldom had an opportunity, unless in the temporary absence of her brother, for original observation. The use of the twenty-feet telescope was not without its exciting and even dangerous features. Sir William Herschel passed his time principally on a high scaffolding, erected with too impetuous haste to be very safe. A temporary cross-beam represented the safe gallery which would have been erected by a more cautious observer; one night in a high wind the whole affair came to the ground; fortunately, says Miss Herschel, the mirror was uninjured. Shortly afterwards, Miss Herschel herself met with a serious accident. She was sent in haste across ground covered a foot deep with snow to record an observation, but the tube and mirror rested on a temporary contrivance, consisting of a couple of butcher's hooks, one of which penetrated her leg above the knee. In answer to her brother's call to make haste, she could only cry that she was hooked. It was found impossible to raise her without, as she says, leaving nearly two ounces of flesh behind her. It was six weeks before the courageous lady asked for medical advice. Dr. Lind, who came to her assistance, told her that if a soldier had received such a wound he would have been sent for six weeks to hospital. Her principal emotion connected with the event seems to have been satisfaction that her brother lost nothing by the accident, as the remainder of the night was too cloudy to afford intervals favourable for observation.
We mentioned that two great objects were present to Sir William Herschel's mind. The first was to obviate the loss of light consequent on the construction of reflecting telescopes; and we have seen by what simple contrivance the change was effected. In his other object, viz., the manufacture of telescopes, powerful beyond the expectations of previous astronomers, he was equally successful. This is not the place for an examination of the expedients he adopted; it is enough to say that, before the discovery of Uranus, he had applied linear magnifying powers of a thousand, twelve hundred, two thousand two hundred, two thousand six hundred, and even of six thousand times to a reflecting telescope of seven feet in focal length. The Royal Society of London officially requested Herschel to give publicity to the means he had adopted for ascertaining such amounts of magnifying power in his telescopes. His answer is contained in a paper called "Answers to Doubts that might be raised to the High Magnifying Powers used by Herschel," and, as Arago says, the question was settled once for all. In one of his letters to his sister, written in May, 1782, when he first went to London, at the king's desire, to see his Majesty, Herschel says:—
Dr. Maskelyne (the astronomer royal) in public declared his obligations to me for having introduced to them the high powers, for M. Aubert has so much succeeded with them that he says he looks down upon two, three, or four hundred with contempt, and immediately begins with eight hundred, he has used twenty-five hundred very completely, and seen my fine double stars with them.
A month later he writes;—
Among opticians and astronomers nothing is now talked of but what they call my great discoveries. Alas! this shows how far they are behind, when such trifles as I have seen and done are called great. Let me but get at it again! I will make such telescopes and see such things—that is, I will endeavour to do so.
It must not be supposed that high powers can often be used in the English climate. Herschel found that there are not above a hundred hours in the year during which the heavens can be advantageously observed with a telescope of forty feet, furnished with a magnifying power of a thousand.
It was not till twenty years of continuous labour had enabled Herschel fully to estimate the value of his discovery that he gave to the scientific world his memoir on the power of penetrating into space by telescopes. He found that with his twenty-feet telescope he could penetrate into space seventy-five times further than with the naked eye; with a twenty-five-feet telescope, he could reach ninety-six times; and with his great forty-feet instrument, 192 times the distance which could be attained by human vision unassisted. As the eye of man can barely discern stars of what is called the seventh magnitude,[15] it follows that the great telescope rendered visible stars so amazingly remote, that light, leaping over a space of a hundred and eighty-five thousand miles, three times the diameter of our globe, in a single second, would take half a million of years to travel from them to the earth. If such a star were this day extinguished, it would still continue to be seen from the earth for 500,000 years.
Such is the domain added by Herschel to astronomy.
In the early part of 1786 the Herschels removed to Slough, and Sir William determined to set to work in earnest on a telescope forty feet in length. He took the twenty-feet as a model. The latter instrument had already been so improved by constant alteration, that it was found practically serviceable for that purpose. His friend Sir William Watson undertook, through Madam Schwellenberg, who was attached to the court, to bring the undertaking under the notice of the king. In consequence of this, he soon afterwards received, through Sir J. Banks, the promise that 2,000l. would be granted to enable him to make himself an instrument. It is nowhere stated whether this sum was defrayed by the Royal Society, of which Sir Joseph was president, or by the king. The work proceeded with rapidity. Smiths toiled all the summer on the ironwork, and troops of labourers relieved each other at the grinding of the great mirror. Tools had to be forged specially for this purpose, ground to be levelled, brick foundations to be laid—in short, the gardens of the new house were the scene of great bustle and activity. The heavy castings were made in London, and brought to Windsor by water. It soon appeared that the expense of these improvements could not be defrayed out of the 200l. a year which was allowed him by the king, or even by the extra 2,000l. procured through Sir William Watson. Moreover, as we gather, the salary was not paid with very great regularity. Sir William therefore established a regular manufacture of telescopes, of which he and his sister ground all the mirrors, and superintended all the details. Though money for necessary household expenses, as well as for astronomical purposes, was thus acquired, Herschel felt keenly that he was doing an injustice to himself and to the cause of astronomy by giving up his time to the making of telescopes for other observers. Mention is made in the journals of several telescopes of remarkable dimensions. One for the king of Spain was executed at a cost of 3,150l. Miss Herschel notes that she was much hindered in her work by the packing of the Spanish telescope, which was done at the barn and rickyard of Upton, where she was then lodging, her own room being all the time filled with the optical apparatus. The Prince of Canino paid 2,310l. for a ten- and a seven-foot telescope from the same indefatigable hands. It is evident that though the pecuniary profit was great, it was dearly purchased at the expense of health and time which was entailed upon Sir William by labour so severe. There is no doubt that the exhaustion produced by grinding mirrors told seriously upon his health.
In the summer which saw them installed at Slough Miss Herschel appeared as an original discoverer. Sir William was called away to deliver a ten-foot telescope as a present from the king to the observatory of Göttingen. While he was absent, Miss Herschel resumed her "sweeping," for which her position as assistant usually left her but little time, but to which she was intensely devoted. Her diary on the 1st of August, 1786, contains the following entry:—
This evening I saw an object which I believe will prove to-morrow night to be a comet.
All next day she steadily pursued her daily task, but it is plain that her mind was running on her comet.
August 2.—To-day I calculated one hundred and fifty nebulæ—I fear it will not be clear to-night, it has been raining throughout the whole day, but now seems to clear up a little. One o'clock: the object of last night is a comet.
Before going to bed that night she wrote to several of the principal astronomers to announce her discovery. To Dr. Blagden she says:—
The employment of writing down the observations when my brother uses the twenty-foot reflector, does not often allow me time to look at the heavens; but as he is now on a visit to Germany, I have taken the opportunity to sweep in the neighbourhood of the sun in search of comets, and last night I found an object very much resembling in colour and brightness the twenty-seven nebulæ of the "Connoissance des Temps," etc.
She then describes the position and appearance of the suspected comet, as she calls it, and adds that her observations were made with a Newtonian sweeper of twenty-seven-inch focal length, and a power of about twenty.
"Sweeping," which was such a delight to Miss Herschel, consists in directing the telescope to a given point in the heavens, and allowing it to remain in that position. By the motion of the earth, all stars situated on the parallel of declination (or distance from the equator) to which the instrument is directed pass across the field in their order of right ascension, and can be recognized by reference to a clock showing sidereal time. When any star or nebula is observed where, according to the catalogues, no star should be, it is noted for further investigation. In one of her letters, many years afterwards,[16] to Sir John Herschel, Miss Herschel mentions the contrivance by which she used to obtain the time. "You mention a monkey-clock, or jack, in your paper. I would only notice (if you mean the jack in the painted deal-case) that Alex made it merely to take with me on the roof when I was sweeping for comets, that I might count seconds by it, going softly downstairs till I was within hearing of the beat of the timepiece on the ground-floor (at that time our Observatory), all doors being open."
Miss Herschel's remark, that she was sweeping "in the neighbourhood of the sun," is possibly an error in the transcription of her letter. The sun had disappeared on the day in question by half past seven; and had that luminary been above the visible horizon, his rays would have prevented the comet from being observed if it had been anywhere in his vicinity. From Miss Herschel's description of the comet's position (in the constellation Comæ Bernices), it was on the day of the discovery about three hours later than the sun in right ascension, and therefore would pass the meridian about three o'clock in the day; at ten in the evening it would be in the north-western heavens, and not very far from the horizon. It is possible that this is what Miss Herschel means by "the neighbourhood of the sun."
The same post which conveyed her letter to Dr. Blagden took also one to her friend M. Aubert, who sent in reply a warm letter of congratulation:—
I wish you joy [he says] most sincerely on the discovery. I am more pleased than you can well conceive that you have made it, and I think I see your wonderfully clever and wonderfully amiable brother, upon the news of it, shed a tear of joy. You have immortalized your name, and you deserve such a reward from the Being who has ordered all these things to move as we find them for your assiduity in the business of astronomy, and for your love for so celebrated and so deserving a brother.
To any other woman such a success would have been a subject at least of some exaltation, but she had no thought for herself. On her brother's return she resumed her place as his humble and unknown assistant without a regret for the career of original distinction which she was foregoing. First and last, Caroline Herschel discovered eight comets. Her journals usually contain such an entry as this:—"August—, 2 A.M., discovered a comet;" and the letter-book of the next day contains transcripts of communications to the astronomers of her own and other nations, giving its declination and right ascension, and "commending it to their protection"—of her own labours or success never one solitary word. Many years afterwards she said, with characteristic modesty, that it was all chance; "I never called a comet mine till several post-days passed without any account of them coming to hand. And after all, it is only like the children's game, "Wer am ersten kick ruft, soll den Apfel haben."[17]
On the 8th of May, 1788, Sir William Herschel married. His wife was a lady of great amiability, and she brought him a fortune which enabled him thenceforth to pursue his scientific career without any anxiety about money matters. Sir William was made happy, but it was the great grief of Caroline Herschel's life. She resigned, as she said, her position as housekeeper, and lived henceforth in lodgings, coming every day to her work, and in all respects continuing the same labours, as her brother's assistant and secretary:—
But [says the authoress of the memoir] it is not to be supposed that a nature so strong and a heart so affectionate should accept the new state of things without much and bitter suffering. To resign the supreme place by her brother's side which she had filled for sixteen years with such hearty devotion could not be otherwise than painful in any case; but how much more so in this where equal devotion to the same pursuit must have made identity of interest and purpose as complete as it is rare! One who could both feel and express herself so strongly was not likely to fall into her new place without some outward expression of what it cost her—tradition confirms the assumption, and it is easy to understand how this long significant silence[18] is due to the light of later wisdom and calmer judgment, which counselled the destruction of all record of what was likely to be painful to survivors.
It is evident from her diary, which was resumed in 1798—though the entries thenceforward are exceedingly brief and business-like—that she never lived beneath her brother's roof again. During his absence from home she would go to his house and put things in order for him; little passages show that at such times she was always at work for him, polishing the brass-work of his telescopes, making curtains for his bookshelves, cataloguing his books and papers; but the day before his expected return she would go back to her lodgings again, whence she would emerge only at nightfall to take her share of the duty of "minding the heavens," as she used to call it. Her brother made her a new telescope, which to the end of his life was her most cherished possession. Letter after letter she used to write during her old age, making arrangements that it should be in safe hands, which would use it tenderly when she was dead. Its ultimate fate is thus spoken of in a letter from Sir John Herschel:[19]—
The telescopes are now, I trust, properly disposed of. Mr. Hausmann (who will value it) has the sweeper. The five-feet Newtonian reflector is in the hands of the Royal Astronomical Society, and it will be preserved by it, as the little telescope of Newton is by the Royal Society, long after I and all the little ones are dead and gone.
The ten years which succeeded her brother's marriage were among the most laborious of Caroline Herschel's life. The Royal Society published two of her works, namely, "A Catalogue of 860 Stars, observed by Flamsteed, but not included in the British Catalogue," and "A General Index of Reference to every Observation of every Star in the British Catalogue." But the most laborious, as well as the most valuable, of her works was the "Reduction and Arrangement in the form of a Catalogue of all the Star-clusters and Nebulæ observed by Sir William Herschel in his Sweeps." It was for this that the gold medal of the Royal Astronomical Society was conferred upon her, and the extraordinary distinction of an honorary membership.
We cannot follow Sir William Herschel through the laborious years which followed. They were a time of intense activity. Not a year passed that he did not signalize with some important memoir in the "Philosophical Transactions." He demonstrated what had hitherto been only suspected, that the sun was not the stable centre of the universe, but that it, together with the planets which form the solar system, was changing its position among the stars. He showed that the direction of our course through space—in company with the sun, our master, and the planets, our companions—is in the direction of the constellation Hercules. It is a fact calculated strongly to impress the imagination, that the sun himself is but a star, among millions brighter, probably, and grander than himself, and that he and all his system of attendant worlds are darting with inconceivable rapidity towards a definite point in space. The establishment of this circumstance in the orderly organization of the universe would alone have made Herschel's name famous. But it is thrown into the shade by other discoveries still more calculated to strike the mind with awe.
There is no branch of astronomy which Herschel might more justly claim for his own domain than that which relates to clustered stars. The catalogue of Meissier contained but sixty-eight nebulæ, to which Lacaille afterwards added twenty-eight, and they were looked upon as mere tracts of luminous matter: their real nature was not suspected. But as soon as Herschel applied to them his powerful instruments, his rare penetration and unconquerable perseverance, this branch of science took a rapid stride. In 1796 he published in the "Philosophical Transactions" a catalogue of one thousand nebulæ or clusters of stars. Three years later appeared a second catalogue, quite as extensive as the first; and that, again, was followed, in 1802, by a third catalogue of five hundred nebulæ.
"Two thousand five hundred nebulæ!" exclaims Arago; such was the contingent supplied by Herschel to a branch of astronomy which had hardly been touched before him. But he was not content with simple discovery. It was his rare good fortune to demonstrate their true nature.
One single nebula out of the vast "contingent" mentioned by Arago, resolved itself under Herschel's telescope into a cluster of fourteen thousand stars! And though not all the nebulæ are resolvable into similar clusters, it is demonstrated by his, and by subsequent observations, that thousands of these beautiful objects are clusters of innumerable stars, so immeasurably distant from us that only their collective light is visible—a dimly luminous point in boundless space.
The immense distance of the planet Uranus, its small angular diameter, and the feebleness of its light, long forbade any hope of discerning from the earth its satellites, if any such existed. It was to the great forty-feet telescope, invented and built by Herschel, that the discovery was due at last. His perseverance was rewarded by a sight of six moons, which revolve around the planet, thus completing, to use the words of Arago, "the world of a system that belongs entirely to himself."
Time went on in the Slough observatory unmarked by any incident external to the scientific labours of its inmates, if we except the birth of his son, Sir John Herschel. Their work, their pleasures, and the events of their lives, were all astronomical. Sir William's position as astronomer to the king brought a constant succession of guests to the observatory who were distinguished by their rank, and his own eminence in science attracted those who were best worth knowing in the world of letters, whether Englishmen or foreigners. Miss Herschel, who liked a quiet joke as well as any one, tells some good stories of her visitors. Some of them, it must be acknowledged, asked very remarkable questions; amongst others, one is recorded of the Prince of Orange, who called one day at the observatory to see Sir William Herschel, but, not finding any one at home, wrote the following note: —
The Prince of Orange has been at Slough to call at Mr. Herschel's, and to ask him, or if he was not at home, to Miss Herschel, if it is true that Mr. Herschel has discovered a new star whose light was not as that of the common stars, but with swallow-tails as stars in embroidery.
About the time when Sir John Herschel, having arrived at man's estate, took his degree as senior wrangler, Sir William's health began to fail. He still pursued his labours, but no longer with his wonted energy, and the journals are filled with remarks which show the bitter grief with which Miss Herschel noted his declining strength. He died in 1822, in the seventy-second year of his age.
The terrible blow of her brother's death seemed to paralyze the energies of his sister, who determined to leave England forever, as soon as the beloved remains were buried out of her sight. She collected the few things which she desired to keep, and retired to Hanover. Her letters from thence to her nephew, Sir John Herschel, are full of recollections of the past, and abound with anecdotes of the great astronomer with whom she passed so many years.
The reader of the memoir will be well able to appreciate the efficient service which Miss Herschel gave to her brother during the forty years of his astronomical work; but she herself did not think so. She always said that a well-trained puppy-dog would have done for her brother everything that she had done; that she was a tool fashioned and polished by him; and that if the tool performed anything worth doing, he was entitled to the credit of it. Thinking nothing of herself, seeking nothing for herself, with an intense power of sympathy, and a noble love of giving herself for the service of others, she transferred her whole personality to the object of her affection. After her brother's death she transferred that affection to his son; she often said that she would have willingly remained at the old observatory at Slough to work under the son, as she had done under the father, but that her strength and health would no longer serve her.
It is sad to think of her in her old age. She was then seventy-two, going back desolate and broken-hearted to the home of her youth. Still more sad when we remember that she was still removed by twenty-six weary years from her rest. She found everything changed. She had been removed from the old familiar paths, and the authoress of the memoir truly applies to her words borrowed from one of Miss Edgeworth's sisters, "You don't know the blank of life after having lived within the radiance of genius."
Caroline Herschel died at Hanover in 1848, at the age of ninety-eight. Her death-bed was attended by the daughter of the Madame Beckedorff, whose acquaintance she had made at the house of the Hanover milliner eighty years before.
One of her nieces, writing to Sir John Herschel an account of her aunt's death, said of her, with true appreciation of her character, "I but too well know that even in England she must have felt the same blank. She looked upon progress in science as so much detraction of her brother's fame, and even your investigations would have been a source of estrangement if she had been with you." A curious illustration of the truth of this remark is found in one of her latest letters.[20] "They talk of nothing in the clubs here but of the great mirror (Lord Rosse's telescope), and the great man who made it; but I have but one answer for all, which is, der Kerl ist ein Narr—the man's a fool."
Her coffin was covered with garlands of laurel and cypress, and palm-branches sent from Herrenhausen, and the service was read over it in the same garrison church in which nearly a century before she had been christened. A lock of her brother's hair, and an old almanac which had been used by her father, were, at her own desire, buried with her.
- ↑ 1. Memoir and Correspondence of Caroline Herschel. By Mrs. John Herschel. London, 1876.
2. Analyse historique et critique de la Vie et des Travaux de Sir William Herschel. Par M. Arago. Paris, in the "Annuaire du Bureau des Longitudes" for 1842. - ↑ Obituary, 1822.
- ↑ "On l'a déjà vu, c'est par la musique qu'Herschel arriva aux mathématiques; les mathématiques à leur tour le conduisirent à l'optique, source première et féconde de sa grande illustration."
- ↑ Memoir, p. 35.
- ↑ Miss Herschel's "Recollections," p. 35.
- ↑ "Les lunettes que construisit Galilée, celles qui lui servirent à decouvrir les satellites de Jupiter, les phases de Vénus et à observer les taches du soleil, grossirent successivement 4, 7, et 32 fois les dimensions Iinéaires des astres. Ce dernier nombre l'illustre astronome de Florence ne le dépassa pas. En remontant autant que j'ai pu faire aux sources où je devais espérer de trouver quelques données précises sur les instruments à I'aide desquels Huygens et J. D. Cassini firent leurs belles observations, je vois que les lunettes de 12 et de 23 pieds de Iong, de 2 1-8 pouces d'ouverture qui conduisirent Huygens à découverte du premier satellite de Saturne et à la détermination de la vraie forme de l'anneau grossissaient 48, 50 et 92 fois; rien ne prouve que ces illustres observateurs aient jamais appliqué à leurs immenses lunettes des grossissements Iinéaires de plus de cent cinquante fois. Enfin une lunette travaillée par Auzont (1664) qui avec la colossale longueur focale de 300 pieds ne grossissait que 600 fois."—Arago.
- ↑ Invented by James Gregory of Aberdeen, 1663.
- ↑ In 1672.
- ↑ Lord Rosse's telescopes.
- ↑ "Je lis le passage suivant dans un mémoire de Lalande, imprimé en 1783 et faisant partie de la préface du tombe v'ii des 'Ephémérides des mouvements célestes.'"
"Chaque fois qu'Herschel entreprend de polir un miroir (de télescope), il en a pour dix, douze, quatorze heures d'un travail continu. Ii ne quitte pas un instant même pour manger, et reçoit des mains de sa sœur les aliments sans lesquels on ne pourrait supporter une si longue fatigue: pour rien au monde Herschel n'abandonnerait son travail; suivant iui, ce serait le gâter." - ↑ Quoted in Chambers's "Astronomy," p. 150.
- ↑ Alexander Humboldt wrote to Miss Herschel on the 25th September, 1846, a letter conveying to her from the king of Prussia the gold medal for science, on the occasion of her ninety-sixth birthday. "I know I may count upon your indulgence. . . . I specially deserve such leniency to-day—the day on which my young friend Dr. Galle, assistant astronomer in our observatory (to the triumph of theoretical astronomy be it said), has discovered the trans-Uranian planet indicated by Leverrier as the cause of the perturbations of Uranus."
- ↑ "Même à l'époque où, dans la ville de Bath, Herschel n'était qu'un simple amateur d'astronomie, il fit jusqu' à deux cents miroirs newtoniens de 7 pieds anglais de foyer; jusqu' à cent cinquante miroirs de 10 pieds, et environ quatre-vingts miroirs de 20 pieds."
- ↑ Hanover, Feburary, 1842.
- ↑ Stars are known empirically as of the first, second, third, etc., magnitude. The theory is that all are of the same size, and dwindle from the first to the second magnitude, and so on in proportion to their distance. This theory is known not to be exactly correct, but it is convenient for astronomical purposes, and is therefore conventionally used.
- ↑ December, 1826, p. 207.
- ↑ " Whoever first calls 'kick' shall have the apple.'—Letter to Lady Herschel, July, 1842, p. 326.
- ↑ She destroyed all her journals and letters from 1788 to 1798.
- ↑ t August 10, 1840.
- ↑ To Sir John Herschel, June, 1844.