Читать книгу Fossils, Finches and Fuegians: Charles Darwin’s Adventures and Discoveries on the Beagle - Richard Keynes - Страница 13

CHAPTER 5

Across the Equator to Bahia

On the day originally fixed for sailing on across the Atlantic to Brazil, FitzRoy was busy on shore complying with Captain Beaufort’s strict instructions that no port should be quitted before not only the magnetic angle, but also the dip and daily variation had been ascertained. On 8 February the instruments were re-embarked, and after swinging the ship and determining less than twenty minutes’ difference in any position of the bearing of the peak eleven miles away, the Beagle weighed anchor and sailed. On 10 February they came alongside the packet Lyra, on passage from London to Rio de Janeiro, and were pleased to find that she was carrying a box of six sounding-leads for them, modified by their designer to operate satisfactorily at depths well below a hundred fathoms. Charles posted a brief letter to his father, in case it might arrive sooner than a long one due to be dispatched from Bahia, in which he said:

I think, if I can so soon judge, I shall be able to do some original work in Natural History – I find there is so little known about many of the Tropical animals.

At sunset on 15 February the St Paul Rocks were seen on the horizon, these being the summit of a sunken mountain, and further from land than FitzRoy had ever seen a group of such small rocks. At daylight next morning the sea was smooth, and while the Beagle sailed round so that Stokes could take angles and make soundings, two boats were sent out to enable FitzRoy, Charles and a party to land on the rocks and examine them. As FitzRoy described it:

When our party had effected a landing through the surf, and had a moment’s leisure to look about them, they were astonished at the multitudes of birds which covered the rocks, and absolutely darkened the sky. Mr Darwin afterwards said that till then he had never believed the stories of men knocking down birds with sticks; but there they might be kicked before they would move out of the way. The first impulse of our invaders of this bird-covered rock was to lay about them like schoolboys; even the geological hammer at last became a missile. ‘Lend me a hammer?’ asked one. ‘No, no’ replied the owner, ‘you’ll break the handle’; but hardly had he said so, when, overcome by the novelty of the scene, and the example of those around him, away went the hammer, with all the force of his own right arm.⁵⁴

In his own account Charles did not deny that he had been somewhat carried away. So he participated in the slaughter of birds on land while a similar struggle to obtain fish for the cooking pot was also taking place in the surrounding waters, both birds and fish being welcome to men who had been living too long on salt provisions. But he nevertheless found time to note that unlike almost all other isolated rocks in mid-ocean, St Paul was exceptionally not volcanic in origin, but was a mineral unfamiliar to him that incorporated streaks of serpentine.^* The surrounding waters were very deep, so that it was the tip of a very large and steeply sided mountain. His conclusion was correct, and the modern view is that St Paul is an important example of the primordial material of the earth’s mantle modified to become the basalt layer of the oceanic crust. The only birds to be seen were boobies, a species of gannet, and noddies, a species of tern; and the only other animals of any size were large tropical crabs of the genus Grapsus. Not a single plant, nor even a lichen, could Charles find growing on the rocks. There were some ticks and mites, and a small brown moth feeding on feathers that could have arrived with the birds; a rove beetle and a woodlouse from beneath the dung; and a large number of spiders that presumably preyed on the other insects. He reflected that since the first colonists of the coral islets in the South Seas were probably similar, ‘it destroys the poetry of the story to find that these little vile insects should thus take possession before the cocoanut tree and other noble plants have appeared’.

The Beagle sailed on. They were now close to the Equator, and preparations were set in hand for the traditional naval ceremonies that accompanied ‘crossing the line’. Soon after dark they were hailed by the gruff voice of a pseudo-Neptune. The Captain held a conversation with him through a speaking-trumpet, and it was arranged that in the morning he would visit the ship.

The proceedings next day were vividly described from memory nearly sixty years later by the then fourteen-year-old Midshipman Philip Gidley King:

The effect produced on the young naturalist’s mind was unmistakably remarkable. His first impression was that the ship’s crew from Captain downwards had gone off their heads. ‘What fools these sailors make of themselves’, he said as he descended the companion ladder to wait below till he was admitted. The Captain received his godship and Amphitrite his wife with becoming solemnity; Neptune was surrounded by a set of the most ultra-demoniacal looking beings that could be well imagined, stripped to the waist, their naked arms and legs bedaubed with every conceivable colour which the ship’s stores could turn out, the orbits of their eyes exaggerated with broad circles of red and yellow pigments. Those demons danced a sort of nautical war dance exulting on the fate awaiting their victims below. Putting his head down the after companion the captain called out ‘Darwin, look up here!’ Up came the young naturalist in wonderment but yet prepared for any extravagance in the world that seamen could produce. A gaze for a moment at the scene on deck was sufficient, he was convinced he was amongst madmen, and giving one yell, disappeared again down the ladder. He was of course the first to be called by the official secretary, and Neptune received him with grace and courtesy, observing that in deference to his high standing on board as a friend and messmate of the Captain his person would be held sacred from the ordinary rites observed in the locality. Of course Mr Darwin readily entered into the fun and submitted to a few buckets of water thrown over him and the Captain as they sat together by one of the youngsters as if by accident.⁵⁵

From Charles’s own account, he was treated with rather less courtesy than King remembered:

Before coming up, the constable blindfolded me & thus lead along, buckets of water were thundered all around. I was then placed on a plank, which could be easily tilted up into a large bath of water. They then lathered my face & mouth with pitch and paint, & scraped some of it off with a piece of roughened iron hoop. A signal being given I was tilted head over heels into the water, where two men received me & ducked me. At last, glad enough, I escaped. Most of the others were treated much worse, dirty mixtures being put in their mouths & rubbed on their faces. The whole ship was a shower bath, & water was flying about in every direction, of course not one person, even the Captain, got clear of being wet through.

Although FitzRoy condemned the practice as an absurd and dangerous piece of folly, he also defended its survival on the grounds that ‘its effects on the minds of those engaged in preparing for its mummeries, who enjoy it at the time, and talk of it long afterwards, cannot easily be judged of without being an eyewitness’.

The Beagle’s next port of call on 20 February was at Fernando Noronha, another isolated group of small islands, where the most prominent feature was a conical hill on the principal island rising very steeply to a peak a thousand feet high, and seemingly overhanging the shore on one side. Near its summit a permanently manned lookout station was maintained by the Brazilian government. According to Beaufort’s programme, FitzRoy was required to verify some measurements of longitude made a few years earlier by another survey ship in pendulum experiments conducted in the Governor’s house.

With the Beagle lying offshore that evening before anchoring in the harbour, Lieutenant Sulivan skilfully harpooned a large porpoise, and moments later ‘a dozen knives were skinning him for supper’. In the morning, landing despite the high surf as near as possible to the house where the previous observations had probably been made, FitzRoy took his shots of the sun and compared his chronometers with those used on shore, while Charles spent ‘a most delightful day in wandering about the woods’. He concluded that unlike the St Paul Rocks, Fernando Noronha consisted of a volcanic rock called phonolite,^* which had probably been injected in a molten state among yielding strata, but was not of very recent origin. The island was thickly covered with trees, often coated with delicate blossoms, though because of the low rainfall their growth was not luxurious, and FitzRoy noted that firewood collected by the crew was full of centipedes and other noxious insects. There were no gaudy birds, no humming birds, and no flowers, so Charles felt that he had not yet seen the full grandeur of the Tropics.

At noon on 28 February the Beagle anchored in the great Bay of All Saints (Baia de Todos os Santos) on the mainland of Brazil, on the north side of which the fine old town of Bahia, now known as Salvador, was situated. The view of the town itself was magnificent, and when next morning Charles had ventured ashore, he wrote in his journal of what he saw with a characteristic aesthetic appreciation, coupled with a strictly practical conclusion:

The day has passed delightfully: delight is however a weak term for such transports of pleasure – I have been wandering by myself in a Brazilian forest. Amongst the multitude it is hard to say what set of objects is most striking. The general luxuriance of the vegetation bears the victory: the elegance of the grasses, the novelty of the parasitical plants, the beauty of the flowers, the glossy green of the foliage, all tend to this end. A most paradoxical mixture of sound & silence pervades the shady parts of the wood. The noise from the insects is so loud that in the evening it can be heard even in a vessel anchored several hundred yards from the shore. Yet within the recesses of the forest when in the midst of it a universal stillness appears to reign. To a person fond of Natural History such a day as this brings with it pleasure more acute than he ever may again experience. After wandering about for some hours, I returned to the landing place. Before reaching it I was overtaken by a Tropical storm. I tried to find shelter under a tree so thick that it would never have been penetrated by common English rain, yet here in a couple of minutes, a little torrent flowed down the trunk. It is to this violence we must attribute the verdure in the bottom of the wood. If the showers were like those of a colder clime, the moisture would be absorbed or evaporated before reaching the ground.

He took many more walks with King or another companion, and after collecting numerous small beetles and some geological specimens, reflected that:

It is a new & pleasant thing for me to be conscious that naturalizing is doing my duty, & that if I neglected that duty I should at the same time neglect what has for some years given me so much pleasure.

Sometimes it was driver ants that caught his attention:

Some of the smaller species migrate in large bodies. One day my attention was drawn by many spiders, Blattaæ [a species of cockroach] & other insects rushing in the greatest agitation across a bare bit of ground. Behind this every stalk & leaf was blackened by a small ant. They crossed the open space till they arrived at a piece of old wall on the side of the road. Here the swarm divided & descended on each side, by this many insects were fairly enclosed: & the efforts which the poor little creatures made to extricate themselves from such a death were surprising. When the ants came to the road they changed their course & in narrow files reascended the wall & proceeding along one side in the course of a few hours (when I returned) they all had disappeared. When a small stone was placed in the track of one of their files, the whole of them first attacked it & then immediately retired: it would not on the open space have been one inch out of their way to have gone round the obstacle, & doubtless if it had previously been there, they would have done so. In a few seconds another larger body returned to the attack, but they not succeeding in moving the stone, this line of direction was entirely given up.

On another day he shot a most beautiful large lizard, but he complained that both here and at Rio de Janeiro, birds seemed to be unexpectedly scarce in the tropical jungle. Had he, however, set up a modern mist net in a clearing, and left it unobserved for an hour, he would have been better impressed by the large number of small birds that would have been caught in it.

Confined on board the Beagle by a badly swollen knee for a couple of weeks, Charles captured a puffer fish Diodon swimming in its unexpanded form alongside the ship, and since he was always interested in the mechanics of animal movements, wrote a closely analysed account of its behaviour, as usual unafraid to contradict the authorities if necessary:

On head four soft projections; the upper ones longer like the feelers of a snail. Eye with pupil dark blue; iris yellow mottled with black. The dorsal, caudal & anal fins are so close together that they act as one. These, as well as the Pectorals which are placed just before branchial apertures, are in a continued state of tremulous motion even when the animal remains still. The animal propels its body by using these posterior fins in same manner as a boat is sculled, that is by moving them rapidly from side to side with an oblique surface exposed to the water. The pectoral fins have great play, which is necessary to enable the animal to swim with its back downwards. When handled, a considerable quantity of a fine “Carmine red” fibrous secretion was emitted from the abdomen & stained paper, ivory &c of a high colour. The fish has several means of defence, it can bite hard & can squirt water to some distance from its Mouth, making at the same time a curious noise with its jaws. After being taken out of water for a short time & then placed in again, it absorbed by the mouth (perhaps likewise by the branchial apertures) a considerable quantity of water & air, sufficient to distend its body into a perfect globe. This process is effected by two methods: chiefly by swallowing & then forcing it into the cavity of the body, its return being prevented by a muscular contraction which is externally visible; and by the dilatation of the animal producing suction. The water however I observed entered in a stream through the mouth, which was distended wide open & motionless; hence this latter action must have been caused by some kind of suction. When the body is thus distended, the papillæ with which it is covered become stiff, the above mentioned tentacula on the head being excepted. The animal being so much buoyed up, the branchial openings are out of water, but a stream regularly flowed out of them which was as constantly replenished by the mouth. After having remained in this state for a short time, the air & water would be expelled with considerable force from the branchial apertures & the mouth. The animal at its pleasure could emit a certain portion of the water & I think it is clear that this is taken in partly for the sake of regulating the specific gravity of its body. The skin about the abdomen is much looser than that on the back & in consequence is most distended; hence the animal swims with its back downwards. Cuvier doubts their being able to swim when in this position; but they clearly can not only swim forward, but also move round. This they effect, not like other fish by the action of their tails, but collapsing the caudal fins, they move only by their pectorals. When placed in fresh water seemed singularly little inconvenienced.

The prevailing rock in Bahia was gneiss-granite.^* An interesting point was that in the immediate neighbourhood of Bahia, the foliations tended to be lined up with the coastline striking E 50°N, in agreement with the observations of Humboldt in Venezuela and Colombia.

It was at Bahia that one of Charles’s most violent quarrels with FitzRoy arose. When he first landed there he was horrified to find himself in a country that was still a haven for ‘that scandal to Christian Nations, Slavery’ by legally importing slaves from Africa. This practice continued, thanks to the dependence of the Brazilian coffee-growers on slave labour, until it was abolished a quarter of a century later in response to sustained pressure from the British government. Slavery was an issue that always aroused Charles’s strongest emotions, brought up as he had been in a family where both of his grandfathers had played prominent parts in the anti-slavery movement during the last twenty years of the eighteenth century, and which numbered influential Whig campaigners for the abolition of slavery among their friends. Two weeks later, Captain Paget of HMS Samarang, when dining with FitzRoy on the Beagle, regaled the company with horrific facts about the practice of slave owners in Brazil. As Charles recorded in his journal, Paget also proved the utter falseness of the view that even the best-treated of the slaves did not wish to return home to their countries. What Charles did not record at the time, but only revealed much later, was the sequel:

Early in the voyage at Bahia in Brazil, FitzRoy defended and praised slavery, which I abominated, and told me that he had just visited a great slave-owner, who had called up many of his slaves and asked them whether they were happy, and whether they wished to be free, and all answered ‘No’. I then asked him, perhaps with a sneer, whether he thought that the answers of slaves in the presence of their master was worth anything. This made him excessively angry, and he said that as I doubted his word, we could not live any longer together. I thought that I should have been compelled to leave the ship; but as soon as the news spread, which it did quickly, as the captain sent for the first lieutenant to assuage his anger by abusing me, I was deeply gratified by receiving an invitation from all the gun-room officers to mess with them. But after a few hours FitzRoy showed his usual magnanimity by sending an officer to me with an apology and a request that I would continue to live with him.⁵⁶

As on other occasions, FitzRoy’s anger was short-lived. Moreover, as he had already shown by his actions, he was always very sympathetic to natives, slaves and underdogs of all kinds, so that his outburst was perhaps more a reflection of his Tory political views than of his true feelings for humanity. Charles’s point was well taken, and when writing from Monte Video to Beaufort in July 1833, FitzRoy said, ‘If other trades fail, when I return to old England (if that day ever arrives) I am thinking of raising a crusade against the slavers! Think of Monte Video having sent out four slavers!!! … The Adventure will make a good privateer!!’ And by the end of the voyage his views on the evil of slavery in Brazil were fully in agreement with those held by Charles.⁵⁷