The Dinosaur Hunters: A True Story of Scientific Rivalry and the Discovery of the Prehistoric World. Deborah Cadbury
Mantell was intrigued to know how Birch’s giant Ichthyosaurus bones compared to the fragments he had found. In March 1820, shortly after the birth of his second son, Walter Baldock, Mantell received an intriguing letter from Lieutenant-Colonel Birch.
‘I am going to sell my collection for the benefit of the poor woman and her son and daughter at Lyme who have in truth found almost all the fine things,’ Birch wrote. ‘I found these people, the Annings, in considerable difficulty – on the act of selling their furniture to pay their rent – in consequence of their not having found one good fossil for near a twelvemonth. I may never again possess what I am about to part with; yet in doing it I shall have the satisfaction of knowing that the money will be well applied.’
Birch was genuinely concerned that the Annings had not been able to maintain their early success. Apart from an Ichthyosaurus uncovered in 1818, they had had no more significant finds. Birch’s sale was planned for 15 May, in the Egyptian Hall in Piccadilly. Gideon Mantell attended the auction and had a chance to see Mary Anning’s ‘marine lizards’: an Ichthyosaur femur and head that was bought for Georges Cuvier in Paris, a partial skeleton, vertebrae and other fossils. Lieutenant-Colonel Birch’s sale raised £400 for the Annings.
Less than a month later, in June 1820, Gideon Mantell entered in his diary: ‘received a packet of fossils from Cuckfield. Among them was a fine fragment of an enormous bone; several vertebrae and some teeth.’ Having met Birch and seen Mary Anning’s giant sea lizards, he immediately wrote that these giant bones must belong to a ‘Proteosaurus or Ichthyosaurus.’ After all, this was the only large creature that had been described in England. Inspired by this discovery of the largest bone he had received so far, he began a series of excursions to Whiteman’s Green in the Weald, the mundane little quarry where workmen laboured for basic stone material, unaware that they were laying bare the secrets of the past. To Mantell the quarry was a magical place; it was like entering the ancient tombs, where extraordinary records of a former world were waiting to be explored. With great enthusiasm, on 16 August 1820 he took the entire family on an outing to the quarry: ‘We made an excursion to Cuckfield; my brother drove the ladies in his chaise and I rode on horseback.’
But the more specimens he found, the more baffling the site became. Strangely, although he believed the animal bones belonged to an Ichthyosaurus, or sea lizard, he began to find the petrified remains of land plants. These fossils were difficult to interpret, some blackened like charcoal, with cracks and fissures filled with white crystalline minerals or the brilliant bronze of fool’s gold. As he scrutinised the stone, he thought he could discern fragmentary remains of leaves, stems and other ‘ligneous structures’, which appeared to be of vegetable origin.
Before 1820, very little was known of fossil botany. In the eighteenth century, Carl Linnaeus had developed a detailed classification system for plants, establishing in his catalogues of several thousand plant species from all over the world the ground rules that a botanist should follow to describe and name plants correctly. Since then, other scholars had occasionally attempted to identify fossil plants, but there were few systematic studies of fossil species before 1820, and names had no legal status. Faced with tantalising impressions of the relics of plants that he could not recognise, Mantell had no knowledgeable source to which he could turn. ‘I am unacquainted with any vegetables either recent or fossil with which these remains can be identified,’ he wrote.
During one trip to the quarry at Cuckfield in 1820 he had a breakthrough. He unearthed, buried with more giant bones, part of a tree trunk more than three feet long, very weathered, with the rudiments of branches. He could see at once that the trunk was covered in distinctive diamond-shaped scars, resembling woody bases where leaf stalks were once attached. This was nothing like the English trees around him, the familiar indentations on the bark of oaks, chestnuts and birches. The roughened surface of the trunk, the pattern of scars from woody leaf stalks, were striking – like those of a tropical palm.
Mantell soon found other fossils, too, which bore more resemblance to a tropical flora. Some of the leaves and stems he thought were like Euphorbia from the East Indies, a lush, flowering shrub. With some confidence he entered in his journal on 17 August 1820: ‘Had a very fine specimen of Euphorbia from Cuckfield.’ Two weeks later, he sent ‘a large and beautiful specimen of fossil Euphorbia from Cuckfield to Mr Greenough … it was embedded in mastic, the same composition as used for the Minerets and Domes of the oriental palace at Brighton’. In fact, flowering plants, like Euphorbia and palms, had not yet appeared on the map of the primitive landscape. The history of fossil plants and the habitat for Mantell’s unknown giant creature were stranger than anything he could anticipate with the limited evidence then available to him.
In 1821, as Mantell was trying to find out more about tropical plants and animals, the Reverend William Conybeare completed his detailed study of Ichthyosaurus for the Geological Society. This was to provide another clue to the giant bones. Conybeare had included beautiful anatomical drawings of the bones of Ichthyosaurus. When Mantell compared the fossil bones that he had uncovered at Whiteman’s Green in the Weald, he found that they were very different from those of the sea lizard of Lyme. The vertebrae of an ichthyosaur were slender and deeply hollowed, allowing for the flexible movements of an animal living in water – nothing like the chunky, solid vertebrae that he had uncovered in Sussex. The leg bone of the Ichthyosaurus was more like the fin of a fish; the slender central bone, the humerus, ‘immediately supporting a very numerous series of small bones, form[ed] a very flexible paddle’. But the portion of giant femur, or thigh bone, that he had found in the Weald bore no resemblance to any bone in the sea lizard. It was truly enormous: the fragment, of the top part of the bone, was over two feet long and twenty inches in circumference. If this fragment of a giant leg was not derived from an Ichthyosaurus, then to what kind of monstrous creature could it belong?
Apart from the shape of the bones, there was another clue that the unknown creature from the Weald was not a sea lizard. When a creature dies at sea, its body sinks down to the ocean floor and is gradually covered by a fine rain of particles that form the new sediments. As it is gradually densely packed with layers of sediment accumulating above, the bony skeleton can be well preserved, just like the ichthyosaurs of Lyme. But when a creature dies on land it is much more likely to be destroyed, falling prey to some other animal or scattered by wind and rain, leaving only a confused jumble of bones. Mantell could recover only fragments of bone from the Weald, never a full skeleton. As yet, he had not even found two bones joined together. It occurred to him that these worn relics of giant bones might have belonged to a creature that spent at least part of its life on land, beneath the shade of palms.
In the quiet of night, when all the town was long since asleep and his medical duties were completed, Gideon Mantell studied the fossils he had found, so utterly absorbed in his work that he was often unaware that the small hours were approaching. With careful use of chisel and hammer, the shape of the bones slowly emerged from the surrounding stone like some strange primordial sculpture, perhaps more impressive than something that is finished, containing all the promise of a great work of art gradually taking shape before his eyes. He would glimpse eerie fragments of the ancient animal: the exquisitely smooth curve of the giant femur, the sharp points of the damaged vertebrae, the strange ridges on the enamel of the teeth; the foramina, or holes, for blood vessels, far larger than any human capillary. It was unearthly.
To try to make more sense of this confusing picture, he would use as a reference Georges Cuvier’s acclaimed four-volume summary, Recherches sur les Ossemens Fossiles des Quadrupèdes, which had been translated into English in 1813. Here Cuvier outlined the details of several species of ancient extinct crocodiles found at Honfleur and Le Havre. Mantell compared his fossils against Cuvier’s drawings, and some of the bones, especially the vertebrae, seemed to correspond. To obtain a second opinion, he now made arrangements to view the Hunterian Museum at the Royal College of Surgeons in London. John Hunter’s collection of ten thousand anatomical specimens had been bought by the government after his death in 1793 and placed in the Royal College at Lincoln’s Inn Fields. Here, they were being catalogued by Hunter’s former apprentice, William Clift.
The child of a poor family in Devon, Clift possessed an exceptional talent for drawing which had been noticed