Darwin and the Barnacle

by Rebecca Stott

  Darwin was always hungry for new ideas, which made him gullible in that first encounter with words and stories and ideas on the written page. ‘It is only after considerable reflection that I perceive the weak points,’ he wrote later, when, as an old man, he was asked to summarize his mental abilities; but at the same time, he said, ‘I am not apt to follow blindly the lead of other men. I have steadily endeavoured to keep my mind free, so as to give up any hypothesis, however much beloved (and I cannot resist forming one on every subject) as soon as facts are shown to be opposed to it.’ He was no sceptic, however. He liked ideas and weighed each with equal attention to claim and evidence, though following abstract logic was sometimes a struggle for him: ‘My power to follow a long and purely abstract train of thought is very limited; I should, moreover, never have succeeded with metaphysics or mathematics’.10

  Other ideas came more slowly, through dialogue, through the hundreds of letters Darwin wrote and received every year. This was speculation in the round – collective speculation, speculation by negotiation and through exchange of information. In 1850 he read James Dana’s book on geology and by letter he and Charles Lyell discussed its implications, so that Darwin continued to shape his ideas about the book, weighing it up, digesting it, in dialogue with Lyell. Sometimes the correspondence was more of a sport than a conversation, such as the series of letters he exchanged with Albany Hancock in 1850, the Newcastle naturalist he had met in 1848 at the British Association meeting. These were detailed and absorbed letters about whether certain barnacles had ‘boring’ powers or not. The two men slugged it out throughout the year, using not pistols or boxing gloves but increasingly detailed evidence taken from their notebooks and from the lenses of their microscopes. Perhaps they each thought that the other would concede out of sheer boredom or fatigue with the weight of evidence being aimed from each side; but neither would concede, and so the letters continued. Even on Christmas Day of 1850 Darwin sat down to write to Hancock, signing off: ‘I hope I have not bored you,’ a pun uncharacteristically unnoticed by Darwin. Like other scientists of his day and ours, Darwin did not discover alone, but through conversation, debate and exchange, a process made possible by a postal system, made possible by railways, made possible by investment and speculation.

  In 1850 Darwin was all too conscious of the power and danger of words, too: wrenching language to tell the story he needed to tell and to do the persuading he needed it to do, like James Dana taking his reader with him up the slopes of a Tahitian mountain to see the evidence conjured up for his mind’s eye. He wrote to Lyell: ‘Dana is dreadfully hypothetical in many parts & often as “d-d cocked sure” as Macaulay. He writes, however, so lucidly that he is very persuasive.’11 In his own writing he knew that if he chose the wrong word or a clumsy inflection, the walls would fall, the picture fade, the evidence collapse. It took so much time to get it right, these words poised delicately against each other within a single sentence, patterned, balanced, holding the reader’s trust for a moment longer, just to carry him or her, like a bridge, through to the next claim.12 If the reader accepted this claim, would she or he accept the next? How far would readers travel with him? Would they be converted? What would it take to get them to see through his eyes?

  So he threw much of his writing away: the mangled sentences, the botched phrases. Then those phrases would return like ghosts to haunt him, for he would find the scraps of his torn manuscript scattered about the schoolroom when the children used the blank backs for their exquisite watercolours and stories. One morning, visiting the empty schoolroom, Charles found red-coated soldiers and gentlemen with large heads and tiny legs, drawn and painted by George, marching across the back of a piece of manuscript.13 As he turned it over, the staccato pencilled phrases of his barnacle classification, smudged and crossed out, brought back all too clearly the memory of an afternoon’s struggle to describe barnacle cement ducts and membranes. This fabulous story about the body of a water creature and how it had come to exist over unimaginable eons of time – this story of valves and apertures and anal orifices shaping in deep time – was this so very different from the fairy tales that George and Annie inscribed on his abandoned manuscripts? It was no less wonderful. He was, after all, a Baron Münchausen amongst naturalists.

  The Ibla and Scalpellum discoveries were the most wonderful of all, he knew, and how to tell this particular story? He wrote to James Dana in February 1850 that Scalpellum ‘[has] revealed to me a wonderful story, but it is too long here to tell you’.14 In writing up his conclusions to the discoveries about the sexual peculiarities of Ibla and Scalpellum, he found it impossible to maintain the critical distance needed to weigh up facts rationally and posit hypotheses. Sometimes the prose would run away with itself even here, in this the most considered and dry of texts that he would ever write; wonder would overtake him at the microscopic communities of creatures he found living together within a single sac of a single barnacle. Oh brave new world that had such creatures in it:

  As I am summing up the singularity of the phenomena here presented, I will allude to the marvellous assemblage of beings seen by me within the sack of an Ibla quadrivalvis, – namely, an old and young male, both minute, worm-like, destitute of a capitulum, with a great mouth, and rudimentary thorax and limbs, attached to each other and to the hermaphrodite, which latter is utterly different in appearance and structure; secondly, the four or five, free, boat-shaped larvae, with their curious prehensile antennae, two great compound eyes, no mouth, and six natatory legs; and lastly, several hundreds of the larvae in their first stage of development, globular, with horn-shaped projections on their carapaces, minute single eyes, filiformed antennae, probosciformed mouths, and only three pairs of natatory legs, what diverse beings, with scarcely anything in common, and yet all belonging to the same species!15

  Speculation was very much on his mind in 1850, in more ways than one. It was to anchor his speculative mind in fact that he had embarked on this barnacle research, and yet the barnacle facts that he had collected from every corner of the Earth were pushing his mind into even more large-scale speculation. In March Charles Henry Lardner Woodd, then twenty-nine, a distant relative and Fellow of the Geological Society, wrote to him from Oughtershaw Hall, a manor house in a tiny hamlet in the Yorkshire Dales, with a paper and a list of pressing large-scale questions about whether masses of metamorphic rock, when heated, would crumple or bow. Darwin tried to answer but ended by transforming the young man’s questions into a new set of his own and then writing in exasperation: ‘how awfully complicated the Phenomenon is’. Woodd’s questions reminded him of his own youth and propensity to unempirical speculation. How to reply? Should he caution Woodd against speculation of this kind or encourage him in this vein? In the end he felt he had to find a way of telling Woodd tactfully to do some careful fact-collecting, to turn his head to tangible evidence, not abstract hypothesizing:

  All young geologists have a great turn for speculation; I have burned my fingers pretty sharply in that way & am now perhaps become over cautious; & feel inclined to cavil at speculation when the direct & immediate effect of a cause in question cannot be shown – How neatly you draw your diagrams; I wish you would turn your attention to real sections of the earths crust, & then speculate to your hearts content on them; I can have no doubt that speculative men, with a curb on make far the best observers.16

  So much of what he read in 1849 seemed to be about this problem: how to conclude, how and when to hypothesize? Even the little sea-side book he ordered and read in August 1850, William Harvey’s Sea-Side Book, was still advocating a purist Baconian method in insisting that naturalists should be ‘patient observers … contented to store up facts’; that they should abstain from ‘all general views that are not warranted by the amount, either of their own knowledge, or of that of the scientific world in general’. The world was full of hasty observers, Harvey warned his readers:

  Deeply informed and comprehensive intellects will discover glimpses through
the haze, like the looming of distant land, where common observers can see no indications of a solution, and their ‘guesses at truth’, being built partly on real induction, partly on skilfully-applied analogies, often open up to us correct views of the order of nature which subsequent discoveries only confirm and strengthen. Such minds will ever be cautious in advancing theories … but how many hasty observers … ignorant of the liabilities of error, and therefore despising caution, rush forward in their course, and propose to the world their fanciful schemes as important discoveries.17

  Harvey presented a very different version of nature from Darwin’s. Harvey’s seashore was divinely ordered and if he was prepared to concede that seashore creatures had transformed through time, it was, he believed, because God had transformed them. Harvey’s warning to young naturalists about the dangers of rash speculation was typical of many of the scientific books that Darwin was reading. What was he, Charles Darwin? A hasty observer, or a naturalist with a deeply informed and comprehensive intellect? When did one turn into the other? Where would the barnacle research leave him?

  20 Microscope

  Of course, it was only four years since Joseph Hooker had pressed him to undertake this damned barnacle work, Hooker who had implied that he had to earn the respect of fellow scientists by undertaking this pursuit of classification of a single minute species. Hooker was now trekking through India and Tibet, seeing all manner of extraordinary sights and speculating with Darwin’s own species theory; Hooker who now – to Darwin’s considerable irritation – seemed to be bored by his barnacle reflections, frustrated that Darwin seemed only to see the dusty detail and not the bigger, speculative picture. He had grown tired of the barnacles and was hungry for news of Darwin’s as yet unveiled and still to be completed species theory.

  In April 1850, Hooker wrote from the Botanical Gardens in Calcutta. He was staying with the Professor of Botany there, Hugh Falconer, who was busy replanting the Gardens and draining and embanking the land. Hooker had become aware from the tone of Darwin’s letter that awaited him at Calcutta that he had given offence to his friend in being less than enthusiastic about his barnacles. He wrote to apologize:

  Probably I spoke too strongly about your specific work & Barnacles, but really I was in periculosis [dangerous or threatening situation] when I wrote & much harassed in mind & body. – was in short seeking & finding a very great comfort in wrapping you round with all my thoughts. I remember once dreaming that you were too prone to theoretical considerations about species & unaware of certain difficulties in your own way, which I thought a more intimate acquaintance with species practically might clear up. Hence I rejoiced at your taking up a difficult genus & in a manner the best calculated to throw light on specific characters their value &c. Since then your own theories, have possessed me, without however converting me & interested as I am in the Barnacles & felt desirous of knowing in what direction they had carried your other views.18

  Then, as if by way of entreaty to forgive, he told Darwin of his own frustrations with Falconer who, whilst Hooker had been off in the mountains, had neglected to forward his mail for five months. Hooker had written to him from prison and from the mountain camps where he had been held hostage to beg him to forward the post, but in the end he had had to implore powerful friends to act as intermediaries. To Hooker’s astonishment, when he reached Calcutta, Falconer’s easy good nature and generosity of spirit made him forget all his anger: ‘a more amiable fellow never lived’, he enthused to Darwin. ‘He had no excuse to offer & plead none – I flared up & forgave him all.’19

  It was all a matter of time. Hooker seemed ambivalent about the barnacle work not because it was a waste of time but because it was absorbing so much time. He was impatient with Darwin, wanting him to get back to the species theory that would make his name. Hooker had never expected, when he urged him to undertake this work, that it would take him so long to complete. Darwin hadn’t realized it would take so long, nor be so frustrating. Two hours of work a day was all he was allowed by Gully, which meant that he constantly had to judge how to invest his time. The motto he had used on the Beagle was all the more important now: Take care of the minutes. He had never forgotten how precious time was, and now Gully’s regime meant that he was constantly looking for ways to save fifteen minutes or ten minutes of working or dissecting time, anxious not to be wasteful. The study was arranged for maximum efficiency: everything within easy reach and drawers carefully labelled, wheels on his chair. No time for rummaging. Emma was the bookkeeper of his time: wherever she was in the house, she knew exactly when Darwin had over run his work allowance and sent a child to him. He knew she was right to do so; she was only carrying out Gully’s orders, guarding his health. It was for the best. He liked the way she managed him.20

  So was the barnacle work worth it? implied Hooker in that April letter. ‘What direction are they taking you?’ he had asked. Darwin, always inclined to play up the labour and play down the theoretical importance of his barnacle work, replied to Hooker in June, drawing attention to the way in which speculation and systematic observation played off against each other in his barnacle work:

  At last I am going to press with a small, poor first fruit of my confounded cirripedia, viz the fossil pedunculated cirripedia. You ask what effect studying species has had on my variation theories; I do not think much; I have felt some difficulties more; on the other hand I have been struck (& probably unfairly from the class) with the variability of every part in some slight degree of every species: when the same organ is rigorously compared in many individuals I always find some slight variability, & consequently that the diagnosis of species from minute differences is always dangerous. I had thought the same parts, of the same species more resembled than they do anyhow in Cirripedia, objects cast in the same mould. Systematic work wd be easy were it not for this confounded variation, which, however, is pleasant to me as a speculatist though odious to me as a systematist.21

  Infinite and confounded variation these barnacles offered. No two pairs of antennae were the same. He may have begun with the notion that all barnacle legs or oviducts had been ‘cast in the same mould’ (signs of design, signs of a creator), but now he was working on the acorn barnacles and wondering whether there had been any common ‘mould’ at all. Which barnacle most closely represented the typical form, the type from which all others could be measured, when there was so much variation? This was worth four years’ investment surely? For it had provided him with proof that the diagnosis of species was itself dangerous.

  Whilst Darwin may have told Hooker that his first book was about to go to press in June 1850, it would not be published until the following year. There were more obstacles ahead. The problems were caused largely by his dependence on the goodwill of fossil collectors who loaned him their collections, and on the postal system, but also by his feeling that he had more barnacles to see before he could write the final conclusive word. A good deal of 1850 was spent negotiating with the collectors. Each time he needed permission from the owner to open up a particular specimen or fossil, for instance, he would have to write a letter and wait for its answer. The postal system was both enabling and frustrating: parcels went astray, letters crossed in the post, his correspondents did not answer quickly enough. Above all, now that the first monograph was reaching completion, he had to hang on the whims of his illustrator, James Sowerby, who was not only excruciatingly slow in his progress with the drawings of cirripedes, but also neglected to reply to his letters. Each month’s delay meant that Darwin had to write more letters to his collectors asking them to tolerate the loan of their collections for another few weeks. He was embarrassed, impatient and eventually maddened by the whole process. Then, when some pictures did arrive from Sowerby, in April, they were inaccurate and overly artistic, so that Darwin had to write again, this time barely able to contain his anger and despair: ‘I do not care for artistic effect, but only for hard rigid accuracy. The inside drawings of the scuta … are useless, from ind
istinctness and shading … I am sorry to … give you the trouble of going over them again.’22

  By August he began to write every week to press Sowerby:

  Please remember how time slips by. – I am plagued to return specimens & only the other day I was asked by Mr Bowerbank on part of Pal. Soc., what progress I was making & I could only answer by stating that everything depended on you. – All this is very disagreeable to me & I do earnestly hope that you will endeavour to make more progress; I know not what to say to those gentlemen, whose specimens I borrowed for only a few weeks.23

  A week later he wrote again: ‘Pray observe how time slips by,’ and a week after that: ‘let me earnestly beg you to put your shoulder to the wheel & get the job done’. His instinct for good manners and politeness was strained to its limit in these letters to Sowerby.

  The book may have been drawing to a close, but Darwin still worried about the barnacles he hadn’t seen. More arrived almost by the week. There was one in Worthing he was particularly worried about; he had seen a drawing of it but felt he should dissect the actual specimen to be sure of its significance. Trouble was, the owner of the collection, Frederick Dixon, a Worthing doctor, had died the year before, and although Darwin knew where the widow lived, he couldn’t bring himself to visit her. Travelling was so exhausting and took up so much time. He went so far as to write to Richard Owen, who had known Dixon, to ask him to write to his widow on his behalf and to ask for the specimen: ‘I certainly do wish much to see it’, he wrote to Owen, ‘but not sufficiently to take me such a journey.’24 He would never see the Worthing barnacle.

  Time was indeed slipping by much faster than he was happy with. This was an anxious year. Emma had given birth to Leonard, their eighth child, in January 1850 and was pregnant again by the autumn. He wrote to Fox in October that he and Emma were thinking about emigration, another kind of life gamble: ‘about midsummer we expect our 8th arrival … I often speculate how wise it wd be to start off to Australia, or what I fancy most, the middle States of N. America’.25 The future of his growing tribe of boys concerned him most. William was attending a local school but would need to go to a boarding school, and Charles and Emma were not happy with the emphasis on Latin grammar that so many schools offered. They began to send away for pamphlets about progressive schools, and in the meantime Darwin continued to speculate about emigration. He wrote to Syms Covington in Australia to ask about prospects in November: