August 1st. I have calculated 100 nebulae today, and this evening I saw an object which I believe will prove tomorrow night to be a Comet. August 2nd. Today I calculated 150 nebulae. I fear it will not be clear tonight, it has been raining throughout the whole day, but seems now to clear up a little … 1 o’clock. the object of last night IS A COMET. August 3rd. I did not go to rest till I had written to Dr Blagden [at the Royal Society] and Mr Aubert to announce the Comet. After a few hours sleep I went in the afternoon to Dr Lind, who with Mr Cavallo accompanied me to Slough with the intention of seeing the Comet; but it was cloudy and remained so all night. August 4th. I wrote today to Hanover, booked my observations and made a fair copy of 3 letters … The night is cloudy. August 5th. I calculated nebulae all day, paid the smith … The night was tolerably fine and I SAW THE COMET.22
Both Aristotle and Galileo had thought comets were low-level atmospheric phenomena, perhaps lower than the moon. The study of comets was improved by the sixteenth-century Danish astronomer Tycho Brahe, but transformed in 1682 when Edmund Halley famously calculated that the Great Comet of that year, subsequently named after him, would reappear in 1759. It was then finally accepted that comets were outer-space objects that moved in extreme elliptical orbits round the sun, and swung far beyond the known planets. Yet they were still mysterious: of unknown origin and composition, various in their appearance, irregular and alarming in their habits. A reassuring popular view, that they were celestial table-waiters, supplying the planets with moisture and the sun with fire, was expressed by James Thomson in his poem The Seasons (1726-30).
From his huge vapouring train perhaps to shake Reviving moisture on the numerous Orbs, Thro which his long elipsis winds; perhaps To lend new fuel to declining Suns, To light up Worlds, and feed the etherial Fire.23
By the mid-eighteenth century only about thirty comets had been identified and recorded in the annual French catalogue La Connaissance des Temps. The greatest comet-hunter of the age, Charles Messier, had personally found about half of these, and so comet-hunting was generally regarded as a French speciality. Caroline’s discovery — even if it had been her only one — would have been an important contribution internationally. Comets (meaning ‘hairy stars’) were significant because they were the only celestial objects which came in from beyond the known solar system, and therefore carried possible information about conditions further out in space.
The fact that the elliptical path of periodic comets could be calculated according to Newton’s laws, and their returns predicted scientifically, seemed to prove that their traditional role as portents of events on earth (usually of sudden disasters) was a meaningless superstition. So the comet that appears in the Bayeux Tapestry turned out to be Halley’s on a previous periodic visit; it reappeared without disaster in 1986, and is next scheduled in 2061. However, new comets such as that of 1811 still caused a great popular stir. Adam Smith noted in his Philosophical Enquiries (1795): ‘the rarity and inconstancy of their appearance, seemed to separate them entirely from the constant, regular, and uniform objects in the Heavens’.24 ♣
It is revealing that Caroline was too excited to sleep, and that in the absence of Herschel, almost her first reaction was to contact her friend and confidant Dr James Lind, who had spoken up for her over the treatment of her wounded leg. The note dashed off to Alexander Aubert is disarming in its modesty, but hints at her sense of obstacles overcome. ‘I hope, Sir, you will excuse the trouble I give you, with my wag [vague] description, which is owing to my being a bad (or what is better) no observer at all. For, for the last three years past I have not had an opportunity to look as many hours in the telescope. Lastly I beg you Sir, if this Comet should not have been seen before to take it under your protection.’25
Privately she still had grave doubts about her own observation skills, and wrote a frankly unscientific ‘Memorandum’ in her Observation Book, admitting that the comet seemed to have a mind of its own, and was not behaving at all as it should. ‘I am at a loss what to think of the path which this Comet may have, by the figures [drawings] of last night it seemed to move downwards but tonights figures show just the contrary. In my letter to Mr Aubert I avoided taking notice of this circumstance … for my wish was only to say what was just necessary by way of delivering it into better hands.’26
Her letter to Charles Blagden, Secretary to the Royal Society and Banks’s right-hand man, produced a dramatic reply by return of post: ‘I believe the comet has not yet been seen by anyone in England but yourself. Yesterday the Visitation of the Royal Observatory at Greenwich was held, where most of the principal astronomers in and near London attended, which afforded an opportunity of spreading the news of your discovery, and I doubt not but that many of them will verify it the next clear night. I also mentioned it in a letter to Paris, and in another I had occasion to write to Munich.’27
The verification of Caroline’s comet was achieved much more rapidly than Herschel’s planet had been. Its movement through Coma Berenices was relatively easy to ascertain, and its fine hazy tail or coma was unmistakeable. Its cometary status was quickly confirmed by Nevil Maskelyne, and on the following evening, 6 August, an impromptu top-level deputation rode down to Slough. Caroline was astonished to receive Blagden himself, Sir Joseph Banks and the MP Lord Palmerston, demanding to see her comet through her special sweeper telescope. Gratefully, she recorded that the evening was ‘very fine’, and everyone was able to get a glorious view of the new visitor, both with her small sweeper and the higher-powered seven-foot telescope.28
Banks was in one of his triumphal moods, and announced that her historic letter would be immediately published in the Philosophical Transactions, where it duly appeared — though after the usual bureaucratic delay — on 9 November, as An Account of a New Comet. In a Letter from Miss Caroline Herschel’. This was her first ever publication by the Royal Society, and an almost unheard-of rarity for a female correspondent.29 Maskelyne was also full of praise, patriotically recruiting Caroline into the new ranks of British astronomy at once. ‘I hope that we shall, by our united endeavours, get this branch of astronomical business from the French, by seeing comets sooner and observing them later.’30 Alexander Aubert, realising the personal significance of the find for her, struck a more intimate note: ‘I wish you joy most sincerely of the discovery. I am more pleased than you can well conceive that you have made it — and I think that your wonderfully clever and wonderfully amiable Brother, upon the news of it, shed a tear of joy. You have immortalized your name.’31
The idea of a female astronomer intrigued people. When William returned from Germany ten days later, on 16 August, he found that Caroline had become something of a celebrity. In September he was summoned to Windsor specifically ‘to exhibit to His Majesty and the royal family the new comet lately discovered by his sister, Miss Herschel’.32 Fanny Burney the novelist, then a lady in waiting to Queen Charlotte, had evinced little previous interest in the stars. But she now suddenly discovered a lively fascination with astronomy, and leaped at the chance to abandon a game of royal piquet and join the viewing party on the Windsor terrace.
To Fanny’s disappointment, Caroline herself was not there (she avoided the Court whenever possible). But the session was interesting ‘for all sorts of reasons’, the glimpse of the comet-catcher’s brother being as fascinating as the comet. ‘We found [Herschel] at his telescope. The comet was very small, and had nothing grand or striking in its appearance; but it is the first lady’s comet, and I was very desirous to see it. Mr Herchel then showed me some of his newly discovered universes, with all the good humour with which he would have taken the same trouble for a brother or a sister astronomer; there is no possibility of admiring his genius more than his gentleness.’33 Fanny was struck above all by Herschel’s total lack of arrogance: ‘he is perfectly unassuming … yet openly happy in the success of his studies’. But she wondered about his relationship with his reclusive sister.
Intrigued, she soon after persuaded her fat
her to take her on a private visit to Herschel’s observatory at The Grove on 30 December 1786. The ‘great and extraordinary man’ received them in his genial manner with open arms, showed them over the unfinished forty-foot telescope in the garden, and talked unguardedly over tea about ‘the new views of the heavenly bodies and their motions’ which it would reveal. Fanny was entranced. She exclaimed excitedly: ‘he has discovered fifteen hundred universes! How many more he may find who can conjecture?’ Charles Burney was also inspired by this visit, and began to compose an extensive ‘Ode to Astronomy’ in Herschel’s honour, which he threatened to read out loud at future convivial suppers.34
By contrast, Caroline Herschel was rather silent, and much more of a puzzle. Fanny Burney evidently tried hard, but failed to get on terms with her. ‘She is very little, very gentle, very modest, very ingenuous; and her manners are those of a person unhackneyed and unawed by the world, yet desirous to meet and return its smiles.’ Those shy smiles seemed to be the extent of their communication. Equally, Caroline did not mention Fanny at all in her day book.35
Other visitors to The Grove had better luck. The German novelist Sophie von La Roche gushingly introduced herself to ‘the great man’s sister, who accompanies him on his path to immortality’. Perhaps Caroline found her fellow-countrywoman easier to placate than Fanny Burney, and made the inspired gesture of picking a bunch of daisies growing in the grass at the foot of the twenty-foot, and presenting them to her as a scientific keepsake. No doubt Sophie was intended to compare them to a star cluster beyond the Milky Way36
Surprisingly, it was Nevil Maskelyne who began to take Caroline’s technical prowess most seriously. A correspondence sprang up between them, and slowly blossomed over the next decade. He later wrote a detailed description of her ‘large’ Newtonian sweeper and her method of working with it. This telescope, built in 1791, was a five-foot reflector with an even bigger aperture of 9.2 inches, but the same low magnification of twenty-five to thirty times, designed for still more effective comet-hunting. Its field of view, being slightly narrower than that of the two-foot sweeper at 1.49 degrees, required even greater familiarity with smaller patterns of the surrounding stars.37 Maskelyne remarked in passing that, like her brother, Caroline knew all the nebulae in the Connaissance des Temps instantly, and sight-read the night sky.38
During these same years Caroline was intensely involved in the final stages of setting up the great forty-foot telescope, intended as the climax of Herschel’s observation work on the nebulae. While continuing her regular night work as assistant on the twenty-foot, she was also helping to organise a vast team of workmen during the day, overseeing the accounts, and trying to bring some order to Herschel’s ever-increasing stream of distinguished and demanding visitors. In autumn 1787 these included the great French astronomer Pierre Méchain, director of the Royal Observatory in Paris and influential editor of the Connaissance des Temps. Praising Herschel for his preparatory work on the forty-foot, he also referred gallantly to ‘Miss Caroline, your worthy sister, whose celebrity will shine down through the ages’.39 When she discovered a second new comet in December 1788, any question of beginner’s luck melted away even in England.40 Her reputation continued to grow, especially in France and Germany.
Caroline remembered 1786-88 as the most intense and exciting years of her and William’s lives. They were both in their prime: in 1786 he was a vigorous forty-seven, she an animated and increasingly self-confident thirty-six. Their teamwork had never been closer. Thanks to Caroline, Herschel published over a dozen new papers with the Royal Society. (‘Very seldom could I get a paper out of his hands in time enough for finishing the copy against the appointed day for its being taken to Town.’41) Their great catalogue of nebulae had long since overtaken Flamsteed, and now stood at over 2,000 clusters, her own reputation as ‘comet-hunter’ gave her an independent scientific standing, and above all the great forty-foot telescope held out the promise of immense new discoveries. Sir Joseph Banks, the Astronomer Royal and the King himself all supported them. Sir William Watson commissioned a bust of Herschel for the Royal Society. Perhaps they would find more planets, new life elsewhere in the solar system, or even new civilisations among the galaxies. By 1789 they would certainly better understand how the universe had been created than at any previous time in history. This moment of scientific optimism coincided with the political optimism in Britain and France. In 1789 the Bastille would fall, and the Rights of Man would be declared.
Caroline’s picture of her brother at this period is heroic, but also unintentionally disturbing in its impression of his single-mindedness. The gentle, humorous, sociable man that Fanny Burney had observed is very little in evidence. Here instead was the man who cut down trees. He was in the grip of his dreams, ruled by a new kind of scientific obsession, intensely focused, workaholic, self-denying. He was driving, driven, indefatigable, omnipresent: ‘The garden and workrooms were swarming with labourers and workmen, smiths and carpenters going to and fro between the forge and the forty-foot machinery, and I ought not to forget that there was not one screw-bolt about the whole apparatus but what was fixed under the immediate eye of my brother. I have seen him lie stretched many hours 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 [the mirrors] 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.’42
The subliminal image of Herschel almost crucified along the top beam of his telescope frame could not have been deliberate. Yet amidst all the bustle and excitement, Caroline slowly became aware of a growing financial crisis, which threatened to bring the entire project to a halt and wreck their fortunes. Over £500 had been wasted on the casting of a first, faulty mirror, a setback so severe that Alexander had urged the mirror’s ‘secret destruction’ because it called into question the whole viability of their casting techniques.43 Herschel had also seriously underestimated the costs of constructing the revolving gantry and paying the workmen for polishing the mirrors. Despite the sales of telescopes, they were threatened by bankruptcy. The whole glorious project could collapse in disaster and humiliation. By the summer of 1787 Herschel had to consider the delicate business of a new application to the King.
It was once again Sir Joseph Banks, the master of scientific diplomacy, who came to his aid. Although the huge half-ton mirrors were not yet finished, there was still a lot to see at The Grove: the great wooden gantry was partly installed on its turntable, now over seventy feet high, zone clocks and micrometers were assembled, and above all the enormous metal tube of the telescope was lying on its side, slumbering on the grass supported by wooden chocks, and ready to be winched into position. It was the moment, urged Banks, to give a Royal Telescope Garden Party.
Accordingly, on 17 August 1787 an impressive cortège of royal carriages rattled down from Windsor Castle, and Herschel and Caroline played host for the afternoon to a glittering party of dignitaries. The company included King George III and Queen Charlotte, the Duke of York, the Princess Royal, the Princess Augusta, the Duke of Queensberry, the Archbishop of Canterbury, many lords and ladies in waiting, a number of foreign visitors, and several distinguished Fellows of the Royal Society, although Banks himself seems to have remained tactfully absent. It was an impressive display which had the subtle effect, just as Banks would have foreseen, of further publicly committing the King to the scheme for which he was the acknowledged benefactor.
It also provided the occasion for another of the royal witticisms, a great additional gain. Caroline remembered it well even fifty years later. ‘One anecdote of the old tube … Before the optical parts were finished, many visitors had the curiosity to walk through it, among the rest King George III and the Archbishop of Canterbury: following the King, and finding it difficult to proceed, the King gave him his hand, saying, “Come, my Lord Bishop, I will show
you the way to heaven.”’44
Now was the precise psychological moment to apply for the royal top-up grant. Herschel drafted a long letter to Banks for submission to the King, explaining the financial shortfall, the replacement of the faulty first mirror, the technical requirements of the gantry (now to be eighty feet high), and the fact that he expected no immediate profits except purely scientific ones. In an elegant formula probably devised by William Watson (if not by Banks himself), Herschel stated that his sole aims were ‘the advancement of astronomy, the honour of a liberal Monarch, and the glory of a nation which stands foremost in the cultivation of arts and sciences’. All details were then costed. The new sum required was huge: £950. But there were also, of course, the continuing running costs, which he estimated could (with careful economies) be kept at £200 per annum. If this increased grant was again assumed to cover operations until 1789, then the total requested (though not specifically stated) was in the region of £1,400 — a very large amount indeed.45
Amazingly, Herschel did not stop there. He also raised through Banks something entirely new: the question of a separate royal stipend for Caroline as his official ‘astronomical assistant’. No British monarch had ever granted a woman a salary, or even a pension, for scientific work before. The very idea that Caroline might be eligible was as novel as that she might be elected to a Fellowship of the Royal Society, or to a professorship at Oxford or Cambridge or Edinburgh. The one concession Herschel made to convention (again probably advised by Banks himself) was that this stipend might come officially from Queen Charlotte. His phrasing was a fine mixture of reason, politesse and provocation. It also contained the interesting claim that the idea for the request had originally come from Caroline herself. She was after all the ladies’ comet hunter.
You know, Sir, that observations with this great telescope [the forty-foot] cannot be made without four persons: the Astronomer, the Assistant, and two workmen for the motions. Now, my good industrious Sister has hitherto supplied the place of Assistant, and intends to continue to do that work. She does it indeed much better, to my liking, than any other person I could have, that I should be very sorry ever to lose her from that office.