The Age of Wonder: How the Romantic Generation Discovered the Beauty and Terror of Science

(#litres_trial_promo)

Caroline was continuing her singing training, and beginning to perform regularly in Herschel’s concerts at the Pump Room. But she ‘could not help feeling some uneasiness’, as she put it, about her future prospects, as more and more of William’s time was ‘filled up with Optical and Mechanical works’.

(#litres_trial_promo) Once they went together to fulfil a singing engagement in Oxford, but Caroline remembered it largely for the perilous journey home, ‘for the jaunt was made in a single horse Chaise, and my Brother was not famous for being a good driver’.

(#litres_trial_promo)

Then William gave her ten guineas-a very considerable sum-to spend on whatever evening dress she liked, for her musical performances. She was overjoyed when the proprietor of the Bath Theatre, Mr Palmer, solemnly pronounced her to be ‘an Ornament to the Stage’, a compliment she never forgot.

(#litres_trial_promo) On 15 April 1778 she was advertised, for the first time, as the principal solo singer in a programme of selections from Handel’s Messiah at the Bath New Rooms. As this was Herschel’s own end-of-season ‘Benefit Concert’, it was clearly he who promoted her. Her performance was such a success that she was offered her first solo professional engagement by a company at the Birmingham Festival for the following spring. Here at last was her chance of an independent career, at the age of twenty-eight. But after consultation with William, she turned it down, announcing that she was ‘resolved only to sing in public where her brother was conducting’. Consciously or not, she had made a decision about her future with William.

(#litres_trial_promo)

It may be no coincidence that the following year, 1779, Herschel began a much more serious and regular pattern of observations. He recorded: ‘January. I gave up so much of my time to astronomical preparations that I reduced the number of my [music] scholars so as not to attend more than 3 or 4 a day.’

(#litres_trial_promo) He had decided on his first major astronomical project: to establish a new catalogue of so-called ‘double stars’.

John Flamsteed had observed over a hundred double stars, but had established no special record of them, and there were obviously many more to be found. The value of double stars was that they might provide a method of gauging the earth’s distance from the rest of the Milky Way, by the measuring of parallax.

(#ulink_eac02a46-1336-5c55-b8d2-4ffb45eac1dc)

Although distances within the immediate solar system-to the moon and notably to the sun (using the Transit of Venus observations)-had been approximately measured, there was no general idea how far away the stars were, or what the size of the Milky Way might be. Kant, for example, assumed that Sirius (the Dog Star), because of its brightness, was probably the centre of the entire Milky Way galaxy, and possibly of the whole universe.

(#litres_trial_promo) In fact it is one of our nearest stars, just over 8.7 light years away.

Most current ideas about the cosmos were small-scale. It was widely believed that the earth was a few thousand years old at most (Biblical calculations gave 6,000 years), and that the universe might stretch out a few million miles ‘above’ the earth. The ‘fixed stars’ revolved in an unchanging pattern, and their brightness or magnitude was probably a function of their size, rather than their distance. So a faint star was probably comparatively small, rather than comparatively far away-a perfectly reasonable assumption. (One of Herschel’s most simple and radical ideas was to assume exactly the opposite.) The physical closeness of the stars and planets also explained their astrological ‘influences’. The universe was small, closely connected, largely unchanging (except for comets), and almost intimate.

Nevertheless, the eighteenth century had been rich in speculative theories about the possibility of a ‘Big Universe’. These included Thomas Wright’s Original Theory or New Hypothesis of the Universe (1750) and Kant’s Universal Natural History of the Heavens (1755), which first proposed-though without observational evidence-that there might be ‘island universes’ outside the Milky Way, that some distant stellar systems might be altering, and that the whole cosmos might be in some sense ‘infinite’, though it was not clear what exactly ‘infinite’ might mean, as hitherto it was a quality possessed only by God and mathematics. Herschel himself had added to these theoretical accounts with an early paper, eventually published by the Bath Philosophical Society, ‘On the Utility of Speculative Enquiries’.

All these speculative essays assumed the high probability that extraterrestrial life existed, either within the immediate solar system, or further out among the stars. James Ferguson, for example, stated in the opening of his Astronomy Explained (1756) that the entire universe was evidently populated, if not positively crowded, with living forms: ‘Thousands upon thousands of Suns…attended by ten thousand times ten thousand Worlds…peopled with myriads of intelligent beings, formed for endless progression in perfection and felicity.’

(#litres_trial_promo) It was further assumed that such life forms, though not necessarily human in appearance, would have developed civilisations and sciences superior to our own. The question of whether they were ‘fallen’ in a religious sense, and required Redemption according to Christian doctrine, remained a moot point among astronomers, few of whom would have considered themselves as ‘atheists’ in any modern sense. ‘An undevout astronomer is mad,’ as the poet Edward Young reflected in Night Thoughts (1742-45).

(#ulink_8825f5aa-1600-51f8-9563-3643a5ea0f58)

However, the growing sense of the sheer scale of the universe, and the possibility that it had evolved over unimaginable time, and was in a process of continuous creation, did slowly give pause for thought. For a poet like Erasmus Darwin, in The Botanic Garden (1791), it put the Creator at an increasing shadowy distance from his Creation.

(#litres_trial_promo)

This interest in extraterrestrial life was one of the reasons that Herschel remained so fascinated by the surface of the moon, with its mysterious mountains and craters, and dramatically shifting patterns and colours of shadow. When it was invitingly at the crescent (the best time to study surface detail), but too low to be observed from his tiny back yard, he would take his seven-foot telescope out into the cobbled street in front of the house. So it was, in December 1779, while Herschel was ‘engaged in a series of observations on the lunar mountains’, that a passing carriage stopped, a young gentleman sprang out, and he had his first historic meeting with Dr William Watson, junior. This was Herschel’s first really important scientific contact in England, one not made until he was forty-one. Watson was only thirty-three.

7

Herschel later recalled the moment with appropriate gravity: ‘The moon being in front of my house, late in the evening I brought my seven-foot reflector into the street…Whilst I was looking into the telescope, a gentleman coming by the place where I was stationed, stopped to look at the instrument. When I took my eye off the telescope, he very politely asked if he might be permitted to look in…and expressed great satisfaction at the view. Next morning, the gentleman, who proved to be Dr Watson, junior (now Sir William), called at my house to thank me for my civility in showing him the moon.’

(#litres_trial_promo)

Caroline remembered it rather less formally. Herschel and Watson were so immediately taken with each other that very night that they burst into the house and began ‘a conversation which lasted until near morning; and from that time on [Dr] Watson never missed to be waiting on our house against the hours he knew my Brother to be disengaged’.

(#litres_trial_promo)

Watson warmly befriended Herschel, and encouraged his work even to the extent of helping with pounding horse-dung moulds and casting speculum mirrors. He quickly became what Caroline called ‘almost an intimate of the family’.

(#litres_trial_promo) He had Herschel elected to the Bath Philosophical Society as ‘optical instrument maker and mathematician’ (no mention of musician), and over the next two years encouraged him to submit no fewer than thirty-one papers at its meetings. These included ‘On the Utility of Speculative Enquiries’, ‘On the Existence of Space’, and further unconventional observations on the moon. They are evidence of the extraordinary intellectual ferment that had seized upon Herschel.

His notion of the cosmos was already far from conventional, and several of these papers were what would now be called ‘thought experiments’. In his ‘Space’ paper, delivered on 12 May 1780, he astonished his audience with his radical thoughts on time and distance: ‘Huygens said that it was possible some of the fixt Stars might be so far off from us that their light tho’ it travelled ever since the Creation at the inconceivable rate of 12 million of miles per minute, was not yet arrived to us. The thought is noble and worthy of a Philosopher. But [should] we call this immense distance a mere imagination? Can it be an abstract Idea? Is there no such thing as space?’

(#litres_trial_promo)

In the case of his moon speculations, he raises the question whether a scientific idea has to be ‘correct’ to be significant. One of Herschel’s most ingenious ideas was that moon craters were artificially constructed circular cities (or ‘Circuses’), built especially to harness solar power for the lunar inhabitants: ‘There is a reason to be assigned for circular Buildings on the Moon, which is that as the Atmosphere there is much rarer than ours and of consequence not so capable of refracting and (by means of clouds shining therein) reflecting the light of the Sun, it is natural enough to suppose that a Circus will remedy this deficiency. For in that shape of Building one half will have the direct, and the other half the reflected, light of the Sun. Perhaps, then on the Moon every town is one very large Circus?’

(#litres_trial_promo)

(#ulink_44d623f1-860b-513f-b83c-62e33d353bc4)

So, besides the two main projects, to record all new double stars and all new nebulae, Herschel was also embarked on a third and partly secret programme in 1779: to discover life on the moon. For some time he did not risk sending this section of the lunar paper to Maskelyne at the Royal Society, but both Watson and Caroline were aware of it. This was one of the reasons he needed to construct better telescopes.

The moon project had begun with a long entry made in his Observation Journal for 28 May 1776. He saw ‘what I immediately took to be woods or large quantities of growing substances in the Moon’. With a certain angle of solar light, some of the lunar shadows looked like ‘black soil’ spread down a mountainside. Other puzzling stippled shadows, especially in the Mare Humorum, Herschel believed were enormous ‘forests’, made up of huge, spreading leafy canopies, or at least ‘large growing substances’. Because of low lunar gravity, this gigantic ‘vegetable Creation’ was evidently ‘of a much larger size on the Moon than it is here’.

(#litres_trial_promo)

Similarly, he tended to believe that there were so many of the smaller moon craters that they must be artificial constructions: ‘By reflecting a little on this subject I am almost convinced that those numberless small Circuses we see on the Moon are the works of Lunarians and may be called their Towns.’ Nonetheless, true science required not speculation but accurate observation and telescopic proof. ‘But this is no easy undertaking to make out, and will require the observation of many a careful Astronomer and the most capital Instruments that can be had. However this is what I will begin.’

(#litres_trial_promo)

The light-gathering power of Herschel’s seven-foot reflector allowed him to see many objects that no previous astronomers had accurately observed, or at least recorded. With Caroline taking notes at his dictation, they began to compose a new catalogue of double stars, and to develop a system of recording the exact time and position of any unusual stellar phenomena not previously catalogued by Flamsteed. By this means Herschel began to build up an extraordinary, instinctive familiarity with the patterning of the night sky, which gradually enabled him to ‘sight-read’ it as a musician reads a score. He would later himself use such musical analogies to explain the technique and art of observation.

In early 1781 it was decided to close down the millinery business at 5 Rivers Street. William and Caroline moved back to the substantial three-storey terraced house at 19 New King Street, where the telescope equipment was immediately set up in the fine little back garden: ‘beyond its walls all [was] open as far as the river Avon’. Here, as Caroline noted modestly, ‘many interesting discoveries were made’. At first she however had to remain at Rivers Street to oversee the selling off of the linen stock, and she missed the first few nights of observation in March. She subsequently recorded, with unusual care, that she did not return to New King Street until 21 March-as it turned out a historic absence.

(#litres_trial_promo)

During these nights around the spring equinox Herschel was observing alone, and as well as continuing with their catalogue of double stars, he gave himself up to making drawings of Mars and Saturn. Possibly he was ranging more freely than usual, or possibly he was testing his ability to ‘sight read’ the sky. At all events, on Tuesday, 13 March 1781, slightly before midnight, Herschel spotted a new and unidentified disc-like object moving through the constellation of Gemini. This discovery would change his entire career, and become one of the legends of Romantic science.

It also raises an intriguing question: how soon did Herschel know-or suspect-what he had discovered? It seems from his Observation Journal at the time, that what he thought he had found was a new comet. The following laconic account appears in his ‘First Observation Book’ for 12 and 13 March 1781

March 12 5.45 in the morning. Mars seems to be all over bright but the air is so frosty & undulating that it is possible there may be spots without my being able to distinguish them. 5.53 I am pretty sure there is no spot on Mars. The shadow of Saturn lays at the left upon the ring.

Tuesday March 13 Pollux is followed by 3 small stars at about 2’ and 3’ [minutes of arc] distance. Mars as usual. In the quartile near Zeta Tauri the lowest of two is a curious either nebulous star or perhaps a Comet. A small star follows the Comet at 2/3rds of the field’s distance.

(#litres_trial_promo)

There are no further remarks for these nights, and certainly no expression of excitement or anticipation. On the following night, Wednesday, 14 March, it was either cloudy, or Herschel did not bother to observe, for there is no entry. He may have been prevented by an official engagement to play the harpsichord at the Bath Theatre, or to rehearse oratorios with Caroline.

(#litres_trial_promo) On 15 March there are short observations on Mars and Saturn, accompanied by some drawings of them made between 5 and 6 a.m., but nothing further about the ‘curious nebulous star or comet’. On Friday, 16 March there is again no entry. But Herschel may have been reflecting on his sightings, and talking to Caroline over the weekend, for finally, on the night of Saturday, 17 March there is the first clear sign that he was definitely in pursuit of the mysterious new object.

Saturday March 17 11pm. I looked for the Comet or Nebulous Star and found that it is a Comet, for it has changed its place. I took a superficial measure 1 rev, 6 parts and found also that the small star ran along the other [cross] wire…Position exactly measured 91′96…

Once Caroline had returned to New King Street on the twenty-first, there are regular entries in late March following the ‘comet’, and attempts to measure its diameter with William’s newly designed micrometer. For example, on 28 March the Observation Book reads: ‘7.25 pm. The diameter of the Comet is certainly increased, therefore it is approaching.’