Fossils, Finches and Fuegians: Charles Darwin’s Adventures and Discoveries on the Beagle. Richard Keynes
shut until sufficient evidence had been accumulated.
Sedgwick’s aim was to follow the line of contact along the Vale of Clwyd between the Carboniferous Limestone cliffs and the Old Red Sandstone, shown in the geological map with ribbons crossing the Vale at several points, starting at Llangollen and finishing at Great Ormes Head on the coast.30 At a quarry near Ruthin they found a possible outcrop of the Old Red, and north of Henllan there was red sand and earth, but Sedgwick was not sure that this established with certainty the nature of the underlying strata. Charles was therefore dispatched on a traverse of his own from St Asaph to Abergele via Betwys-yn-Rhos, crossing a substantial band of Old Red shown on the map. Finding in some places a few loose stones and some reddish soil, he noted: ‘It was in such points as these where the strata have been much disturbed, that I observed the greatest number of bits of Sandstone, but in no place could I find it in situ.’31 Near Abergele the soil was indeed ‘very red’, but this he attributed ‘entirely to the very ferruginous [rich in iron] seams in the rock itself, & not to the supposed sandstone beneath it’. That evening he told Sedgwick that there was no true Old Red to be seen, and to the end of his life could remember how pleased his teacher had been with this new evidence that the Vale of Clwyd did not have a complex structure as had been supposed, but was a simple trough-like syncline* resulting from a stretching of the strata. Although his experience of geology in the field was thus limited to just one week, Charles had sat at the feet of a master, and had solved his first problem with conspicuous success.
Geological map of part of North Wales, redrawn by Secord15 after Greenough,30 with Charles’s route from Llangollen to Penmaenmawr as a dotted line. In the second edition of Greenough’s map, published in 1839, the Old Red Sandstone had disappeared.
Among other sites of geological interest in the Vale were the famous caves in the limestone cliffs at Plas-yn-Cefn, above the River Elwy. Here the owner had excavated vertebrate fossils in the largest cave that included the tooth of a rhinoceros, and there were other bones in the mud. Charles’s imagination was fired by the prospect of making similar discoveries from past worlds in his projected trip to the Canaries, though his hopes were not in fact realised until his arrival in 1832 at the cliffs of Punta Alta in Patagonia. After a week, Charles and Sedgwick separated at Capel Curig in the neighbourhood of Bethesda, and Charles strode on across the central mountains of Wales, steering by map and compass, to join some Cambridge friends at Barmouth.
Reaching home at Shrewsbury on 29 August 1831 after two weeks of shooting with his Uncle Jos at Maer, ‘for at that time I should have thought myself mad to give up the first days of partridge shooting for geology or any other science’, Charles found the fateful letter from Henslow proposing that he should sail on the Beagle. The clock must next be turned back to explain its origin.
The Strange Consequences of Stealing a Whale-Boat
On 25 September 1513 the Spanish explorer Vasco Núñez de Balboa crossed the narrow isthmus joining the two halves of the American continent to discover on the far side the Mar del Sur, later named the Pacific Ocean. The town of Panama was built on the Pacific shore, and became the base for a rapid expansion by the Spaniards. While Hernán Cortés was conquering the Aztec empire in Mexico, Francisco Pizarro was overcoming the Incas in Peru. During the next three hundred years prosperous Spanish colonies were established in the western and southernmost parts of South America, while in the east the Portuguese took over a large area in Brazil.
The English were jealous of their success, but for a long time could only benefit from it by robbery, following the example of Sir Francis Drake when he returned from his circumnavigation in 1580 with a rich cargo of treasures stolen from the Spanish colonies at Queen Elizabeth’s behest. In 1806 Buenos Aires was attacked by a British force, which was successfully repelled, giving the Argentinians the confidence to join the other Spanish colonies in breaking away from Spain. By 1820 they were all independent countries, though not always at peace with one another.
The Hydrographic Office of the Royal Navy, founded in 1795, was initially responsible for looking after the Admiralty’s collection of navigational charts, and of the ‘Remark Books’ about foreign shores and harbours that all naval captains were required to keep. In 1817 the second Hydrographer, Captain Hurd, was empowered to recruit some surveyors of his own, and had soon built up a programme of a dozen Admiralty surveys in home waters and abroad. Trade was quickly building up with the new governments of South America, and there was a need both for a British naval presence in South American waters, and for accurate charts of the coastline to assist shipping. Hence it came about that:
In 1825, the Lords Commissioners of the Admiralty directed two ships to be prepared for a Survey of the Southern Coasts of South America; and in May of the following year the ADVENTURE and the BEAGLE were lying in Plymouth Sound, ready to carry the orders of their Lordships into execution. These vessels were well provided with every necessary, and every comfort, which the liberality and kindness of the Admiralty, Navy Board, and officers of the Dock-yards, could cause to be furnished.32
HMS Adventure was a ‘roomy’ ship of 330 tons, without guns, under the command of Captain Phillip Parker King. HMS Beagle was a smaller vessel of 235 tons, rigged as a barque carrying six guns, and commanded by Captain Pringle Stokes. On 19 November 1826, Adventure and Beagle sailed south from Monte Video, and until April 1827 carried out surveys in the south of Patagonia and in Tierra del Fuego, around the Straits of Magellan. In June 1827 they arrived back at Rio de Janeiro. Six months later, now accompanied by a schooner named Adelaide to assist in the surveys – for whose purchase Captain King had prudently obtained Admiralty approval in advance, unlike Captain FitzRoy when in 1833 he bought the second and smaller Adventure – they sailed south again. In January 1828 the Adventure was anchored for the winter at Port Famine. Captain Stokes was ordered in the Beagle ‘to proceed to survey the western coasts, between the Strait of Magalhaens and latitude 47° south, or as much of those dangerous and exposed shores as he could examine’, and to return to Port Famine (Puerto Hambre) by the end of July. Captain King allotted himself a more comfortable task in the Adelaide, charting the southern parts of the Strait relatively close at hand, and collecting birds and plants.
When at the appointed time the Beagle returned to Port Famine with her difficult assignment conscientiously completed, Captain Stokes was found to be in a state of acute depression thanks to the extreme privations and hardships that he and his crew had suffered from very severe weather, both stormy and wet, when working in the Gulf of Peñas. On 1 August 1828 he tried unsuccessfully to shoot himself, and although the surgeons thought for a while that he might recover, he died in great pain on 12 August. He was interred at the Adventure’s burial ground, the so-called English Cemetery two miles from Port Famine. (The tablet erected to his memory has since been moved to the Museo Saleciano in the modern town of Punta Arenas, some forty miles away along the Straits of Magellan.)
The Adventure and the Beagle, temporarily commanded by her First Lieutenant, William Skyring, sailed back to Rio de Janeiro in October for repairs and replenishment of their stores. Here Admiral Otway, Commander-in-Chief of the South American Station, appointed his young Flag Lieutenant, Robert FitzRoy,* to take over command of the Beagle in succession to Captain Pringle Stokes. His choice was successful, and FitzRoy had soon overcome the handicap of restoring the morale of a demoralised ship’s company well enough to