Darwin and the Barnacle

by Rebecca Stott

  The sea-shore is a sort of neutral ground, a most advantageous point from which to contemplate this world … The waves forever rolling to the land are too far-travelled and untameable to be familiar. Creeping along the endless beach amid the sun-squall and the foam, it occurs to us that we, too, are the product of sea slime.

  Henry David Thoreau, from Cape Cod

  From Carlton Hill, in Edinburgh, Darwin’s eyes would have followed the line of the wide street of Leith Walk, lined by fields and terraces of elegant houses, all the way down to the harbour of Leith. Beyond the harbour, the Firth of Forth, grey and steely in the winter light, stretched out from left to right, peppered by fishing boats and single-masted oyster boats. The shoreline view in 1825 was dominated by four cone-shaped brick mounds down on the sands of Leith, like giant brown barnacles between Darwin and the sea, which only a year before would have trailed smoke into the sky. These were the kilns of the Leith Glassworks Company, which had fallen into bankruptcy in 1825 because of high taxes on glass. They were already felling into disrepair; but the sea-bathing industry was growing. Seafield Baths, with seventeen hot, cold and tepid baths, a large plunge bath and hotel accommodation, had been trading successfully since 1813 and the number of bathing machines lined up on the sands grew from year to year. A regular plunge into a cold sea, doctors claimed, would restore an ailing body to a natural state of health. The sea acted as an antidote to the corporeal corruptions and pollutions of the industrial city, by restoring balance and circulation.

  The two brothers, Charles and Ras Darwin, had arrived in Edinburgh in late October 1825. In studying medicine at Edinburgh, Darwin was walking a family route – his brother, father and grandfather had all enrolled as medical students there. After spending a few nights at the Star Hotel in Princes Street, they found lodgings four flights up at 11 Lothian Street with a Mrs Mackay: two bedrooms and a sitting room that were ‘very comfortable & near the College’.1 Darwin’s first impressions of Edinburgh were of its gloominess; but their lodgings, he noted in a letter to his sister, were remarkably well lit compared to some of the ‘little holes’ he had seen. Light would be important here – for reading, for writing up his lecture and reading notes, and for his microscope.

  For the next two years these small rooms would be a place of intense concentration, for although Darwin was later critical about his experience of University life in Edinburgh and gave the impression that he didn’t achieve much, he and his brother read voraciously. The curriculum at Edinburgh was based entirely upon lectures, some held as early as eight o’clock in the morning; but they were not enforced, and Darwin found them very varied in quality, as he wrote to his sister in January 1826:

  As you know nothing either of the Lectures or Lecturers, I will give you a short account of them. – Dr Duncan is so very learned that his wisdom has left no room for his sense, & he lectures, as I have already said, on the Materia Medica, which cannot be translated into any word expressive enough of its stupidity. These few last mornings, however, he has shown signs of improvement & I hope he will ‘go on as well as can be expected.’ His lectures begin at eight in the morning. – Dr Hope begins at ten o’clock, & I like both him & his lectures very much. (After which Erasmus goes to Mr Lizars on Anatomy, who is a charming lecturer) At 12, the Hospital, after which I attend Munro on Anatomy I dislike him & his Lectures so much that I cannot speak with decency about them. He is so dirty in person & actions – Thrice a week we have what is called Clinical Lectures, which means lectures on the sick people in the Hospitals – these I like very much. – I said this account should be short, but I am afraid it has been too long like the Lecturers themselves.2

  Darwin confessed to his sisters in letters that he found all his lectures dull and preferred to follow his own intellectual curiosity in self-directed reading; but his elder sister, Catherine, who had filled his mother’s role after his mother’s death, was concerned and spoke to their father. Robert Darwin, a powerful man of great direction and drive, was shocked at his son’s lack of application: ‘If you do not discontinue your present indulgent way, your course of study will be utterly useless,’ he wrote fiercely, dictating to Susan.3 He was also anxious about the health of his two sons in the fierce Edinburgh winters and advised them to remember to wear the special fleece vests he had sent them. Ras, instinctively reclusive and frail in health, was reluctant to socialize with fellow students, so the brothers had a good deal of time on their hands for reading. Between them, they signed out more books from the University library in their first term than most other students did in that year. Among these were books on zoology, at this point in the history of science one of the most philosophical of the sciences.

  Although Darwin had been sent to Edinburgh with the expectation that he would become a doctor, he quickly found that surgery turned his stomach and that his intellectual interests ranged beyond medical questions. He also discovered in 1826 that his future inheritance would be large enough to make it unnecessary for him to earn his own living. This belief, as he said himself, ‘was sufficient to check any strenuous effort to learn medicine’,4 but it also gave him the freedom to be an intellectual dilettante and in an environment that encouraged independence of mind. He had the butterfly-like curiosity of a sixteen-year-old. In January 1826 he may have been skipping lectures, but he was busy filling his notebooks with zoological observations and taking private taxidermy lessons from a black taxidermist who lodged in the same street.5 He wanted to be able to stuff birds.

  Freed from parental authority, the two brothers roamed the city, drinking porter and eating oysters in the candlelit taverns, visiting the theatre, dining with old friends of their father’s. It was a city full of drama and contrasts, with high-rise tenements built on the steep sides of the craggy hills. A sharp and steep ravine dissected the city so that the two sides had to be linked by bridges – a jagged urban skyline surrounded by jagged hills; and a castle perched on top of a mountain in the midst of it all. But whilst Edinburgh may have been elegant – ‘stately Edinburgh throned on crags’, as Wordsworth called – it the Old Town slums were dangerous and desperate places. The brothers explored the markets held down in the deep ravine that divided the city. Behind the covered stalls of the fish market, rows of fisherwomen bantered loudly with their customers over the wicker baskets of pilchards, cod, haddock, herrings, mackerel and lumpfish, demanding three times the price they expected so as to start the bartering high. Darwin would often have woken to the sound of the cries of fisherwomen selling clams, mussels, prawns and oysters on Edinburgh street corners in the early morning.

  Meanwhile, Darwin was using his private income and the marine invertebrates he found at Leith to think through philosophical questions about the origins of life, questions that were now of a distinctly aquatic character. In conversation with the other young men of the student societies of Edinburgh, he would continue to philosophize about the sea creatures he found at Leith and Newhaven. Like Grant before him, he had read his grandfather’s book, Zoonomia, in 1826, and like Grant he had questions about the body structures of certain marine invertebrates that the shores of the richly fertile Firth of Forth could help him answer. Later, at Cambridge University, with no ready supply of sea creatures to dissect, he would turn his attention to the body structures of insects and begin to see important points of connection between them and certain sea creatures; but here the zoological riddles that taxed his mind came chiefly from the rock pools of the Firth of Forth.

  That year Darwin was also reading a book by a notable Scottish naturalist, John Fleming, called The Philosophy of Zoology. Fleming, a minister of Flisk, a tiny fishing village with a population of 300 on the banks of the Tay in Fife, was a passionate collector of sea creatures, but he rejected transmutation or development as a way of explaining the variety of anatomic structures under the sea. These ideas had not yet been absolutely proved, he claimed. Yet his zoological observations of marine creatures were making him face up to disturbing questions. He couldn’t de
ny that some sea creatures seemed to slip between the absolute categories marked out by Cuvier. Creatures like the infuriating sea sponge defied established systems of classification. Although there was much to suggest that the animal and vegetable kingdoms had once been joined,6 he wrote, there were some absolute differences between animals and plants that could not be denied. He was working with a similar set of definitions to Grant’s: sensation, independent movement and digestion were the three critical distinctions between animals and plants. These were also Darwin’s seashore preoccupations from as early as January 1826. Grant’s, too; but the two men had not yet met.

  In February 1826 Darwin returned with his brother to the sands of Leith. Ras, wading out in the water, caught a cuttlefish in his dredging net, a weird, squid-shaped cephalopod, about eight inches long, with a ring of ten arms round its large mouth and a body sac filled with blackish fluid. The brothers watched it thrash about in the net, then released it to watch its strange movements in the water. Darwin noted in his red notebook that its mouth ‘had a bill, like a parrot’s’ inside its ring of suckered arms. It had huge eyes, too, bright lizard-like eyes on either side of its beak. It hovered and darted about very quickly in the water like a jellyfish, all tentacles and suckers, fanning its fins and sometimes forcing a stream of water, siphon-like, through a body opening behind its head. Darwin checked its classification back in the textbooks in Lothian Street: Loligo sagittata – Barbed fish.

  Two days later Darwin explored the ridge of rocks that at low tide look as if they have been scattered along the grey sands from Crammond round to Prestonpans. They were – and still are – black with mussel shells. Against this gleaming black rocky crowd of mussels and barnacles, growing in and over each other in their thousands, Darwin’s eyes caught sight of a flash of bright orange, a globular zoophyte. He prised it out from its rock hole and placed it in a basin of seawater – a basin he had carried with him down the hill from Edinburgh. It immediately turned itself inside out like a glove. So he prodded it with his stick and it reversed the process. This time he carried the basin back up Leith Walk to his lodgings and slipped the animal into a jar of wine spirits, where it instantly ceased its aquatic contortions.

  In the final days of February the night’s storms took Darwin back down to the sands. Here he found that the pools of water left by the sea around the black rocks were full of bright-red sea anemones. Under the still-stormy sky and against the wet, black rocks they gleamed like glossy strawberries. Gingerly, he pulled one or two from the rock and placed them carefully into his pan of seawater. They were cold and slimy, difficult to grasp. Like the zoophyte, once pulled from the safety of the rock and frustrated by the slippery surface of Darwin’s bowl, they gyrated and twisted and turned themselves inside out, entirely changing the shape of their bodies. Inside each of the strange cylindrical rocks that covered the black rocks he found a Pholas candida, about half an inch deep. These sack-like creatures had found a way of boring into rocks and no-one knew quite how. Some said they emitted phosphoric acid; others that they used mechanic abrasion for boring. They were also luminous. At night the rocks, lit up, glowed under the moonlight.

  The shore itself, after the night’s storms, was littered with the bodies of still-live, twitching cuttlefish; there were glossy tentacles everywhere on the shoreline, twisted up with the dark-green sea weed, mussel shells and driftwood. They were enormously sensitive, Darwin noted. He prodded them with his stick and they squirted a dark-coloured liquid on to the sand. Darwin was sure that they had begun to squirt even before he touched them: they seemed to be sensitive to the slightest movement. So he experimented, creeping up on them to monitor their sensitivity. Everywhere along the sand the cuttlefish were oozing black ink as Darwin played Grandmother’s Footsteps with them. This cuttlefish liquid is called sepia, which, when dried to a fine power, was used in ink production. The brown ink that Darwin used in his red notebook in 1826 may even have contained some of this pigment derived from dried cuttlefish sacs. Before he turned away to wander further along the sands, he lifted a few limp cuttlefish back into the water to watch them swim.7

  Darwin picked up a starfish here, too, with only three arms, the other two having been torn off by the violence of the storm-driven waves; but he noticed in wonder that even just a few hours since the storm had abated, two new arms had begun to grow. The starfish repairs itself again and again. In March, alone in Edinburgh after Erasmus’s departure for London, he found spawning starfish and more sea mice at Leith. Growing more confident, he picked them up with his stick and threw them back into the sea, where they rolled themselves up like hedgehogs. The shore in March was full of hideous, jelly-like creatures: a yellowish globular mass called a sea wash ball, a three-foot green worm with numerous feet on each side and a nose an inch long, with dot-like eyes.

  So why so much prodding and poking? Why was the sixteen-year-old Darwin so interested in the acrobatics of these creatures – so much so that he would prise them off their rocks in order to watch them dance in his bowls of sea water? What questions was he asking of the cuttlefish and the sea mice in Leith in 1826? The experiments he conducted on these creatures give us further clues about his questions. His notebooks show that he was interested in how they moved and how sensitive they were, because these questions would help him understand their place in nature, particularly their animal or vegetable status. These questions had also troubled Erasmus Darwin and Jean-Baptiste Lamarck, and ten miles east round the coast in a high-walled house in Prestonpans, they continued to trouble Robert Grant.

  That summer, away in Wales on a walking holiday during his university vacation, Darwin missed seeing a luminous meteor that lit up the evening skies of Edinburgh on Sunday, 27 August. The sky hung heavy for some time beforehand, meteorologists noted. Suddenly a large body of fire, pear-shaped, and apparently the size of a beehive, moved across the sky from the south-west to the north-east with a rushing noise and turned the night sky as bright as day. It left behind it a very long train, not of sparks, but fluid-like and of the brightest prismatic colours, mirrored in the waters of the Firth of Forth.

  John Coldstream, another young medical student at the University and now a protégé of Robert Grant’s, was on the shore of Leith to see the comet and record it in his diary that evening. He had a particular interest in comets, the aurora borealis and the sea sponges of the Firth of Forth. Like Grant, he had been born at Leith, attended Edinburgh High School and graduated to the Medical Faculty of the University. Like Grant, he had been building an invertebrate collection since childhood. Unlike Grant, he was religious. However, the more he collected and studied marine creatures, the more his scientific and religious beliefs came into conflict. In the early days, when he was a member of the Leith Juvenile Bible Society, the abundant life of the shoreline had been a constant testimony to the benevolence of God. At fifteen, he had stood on the sands of Leith at dawn on a winter morning in 1821 and recorded the sight in his diary:

  5 Leith Pier and Harbour, 1798

  This morning as the storm subsided, I determined to go down to the sands at Leith that I might revel in the riches which might have been cast up by the deep after the terrible storm. First I went to the end of the pier. I saw a most beautiful sight. As the sun was rising, his rays dissipated a thick frosty fog which hovered around; this rose like a curtain on the horizon, and displayed the whole coast of Fife clothed in snow, and reddened by the sunbeam; a large number of vessels lying at anchor in the Roads on account of the storm; dark blue waves rolling in silent majesty, undriven by any wind, and all forming the grandest coup-d’oeil I have ever seen. Returning thence, I strolled along the sands, past the baths, and picked up a number of curious things. There was a scarcity of shells, but asterias, actinae, aphrodites, and crabs were very common. I brought several home, along with a fine specimen of the Cyproea islandica, a new coral &c. I added an Aphrodite aculeata to my menagerie of living animals.8

  From 1823, when his marine interests brought him i
nto the company of the sponge doctor, Robert Grant, Coldstream’s diaries record a sudden change in his personality and outlook. He was seventeen when he met Grant and his journals from 1823 record a painful story of self-blame, torment and physical self-loathing. On his eighteenth birthday, 19 March 1824, for instance, he wrote:

  My praise is altogether an unclean thing; my glorifying of the Lord is filthiness before Him. From the dust do I cry unto thee, O God! Hear me, hear me. I earnestly beseech Thee to purify my heart … I am at a time of life when the amusements of this little world lead me away into temptation; now, heavenly Father, point out to me in what measure I should best enjoy these, that all my conduct may be to Thy glory. Oh, were I prepared, how I would fly from the attractions of the flesh.9

  But Coldstream didn’t leave the Plinian Society, nor the company of the doctor. He continued to struggle with his religious doubts and with a certain mysterious sense of personal corruption focused on his own sexual body during these years.10 He became one of the Society’s presidents in 1824–5 and one of the doctor’s closest companions, collecting sea sponges for him and for the Museum of Natural History at the University. He also was always on the lookout for other young naturalists who might be nominated for membership of the Society. He published regularly in the Edinburgh Philosophical Journal – articles on the springs of Ben Nevis, the saltiness and transparency of the water of the ocean, on hoar frost, on the aurora borealis, which he saw out in the Firth of Forth on his nineteenth birthday, in 1825, and on the sea sponges and the zoophytes of the Firth of Forth. The Firth, its sea creatures and meteorological phenomena were the primary source of his scientific and philosophical speculations; but they were also to drive him to ask questions he did not want to ask and which would eventually drive him to moral and religious breakdown in 1828.