I have one dug out of a quarry in the Parish of Cornwell, and given me by the ingenious Sir Thomas Pennyston, that has exactly the Figure of the lowermost part of the Thigh-Bone of a Man or at least of some other Animal, with capita femoris inferiora, between which are the anterior … and the large posterior Sinus: and a little above the Sinus, where it seems to have been broken off, shewing the marrow within of a shining Spar-like Substance of its true Colour and Figure, in the hollow of the Bone. In Compass near the capita femoris, just two foot, and at the top above the sinus measures about 15 inches: in weight, though representing so short a part of the Thigh-Bone, almost 20 pounds.5
His suggestion that this came from an animal proved to be prescient, and for a time he interpreted the bone as coming from a Roman war elephant, though his later interpretation was that it came from a gigantic human.6 Philosophers at the time accepted that 10-foot (3-metre) giants had lived in the past, for they were mentioned in the Bible.7
What Plot was describing was actually the end of a fossilized long-bone. His published engraving is the first we have of a dinosaur bone, even though nobody at the time realized its significance. Plot himself was an enthusiastic naturalist and collector who met many of the luminaries of his day and carefully cultivated their acquaintance. Plot saw himself as Britain’s answer to Pliny the Elder; just as Pliny had written his Natural History, so Plot resolved to publish a Natural History of his own that would commemorate his lifetime’s work.8
Plot’s description of the fossil was meticulous, though he did not assign a scientific name to the specimen. His illustration was re-published by Richard Brookes in 1772. Brookes was a physician and naturalist who wrote a great many books on British wildlife, and his desire to categorize species correctly obliged him to find a suitable designation. Considering its appearance, and disregarding Plot’s attempt at a detailed description, it seemed to Brookes that he knew what it was. There was only one name that unambiguously summed up its appearance: in the fourth volume of his New and Accurate System of Natural History he boldly named it ‘Scrotum humanum’. It certainly looked like one.9
This fossil was found in the Stonesfield quarry near Oxford in 1676 and given to Robert Plot. He identified it as ‘Scrotum humanum’ but is it actually part of a Megalosaurus. His published engraving was the first illustration of a dinosaur bone.
Observation and the art of seeing were becoming a philosophical preoccupation of the learned classes at this time; it was even the subject of literature for children. A six-volume book entitled Eyes or no Eyes; or, the Art of Seeing, written by John Aiken and his married sister Anna Barbauld, was published in 1780. It told the tale of two brothers who walked together in the countryside; one finding it a tedious trip, with nothing of interest, while the other was endlessly engaged in the plant species that they encountered, the myriad insects and meadow creatures he could see, and the geology of the landscape – even finding traces of a prehistoric encampment. It was not what you could see that mattered, but what you perceived. The book was so popular it was frequently republished and remained constantly in print for well over a century.10 So successful was the book that the celebrated W. S. Gilbert and Arthur Sullivan later wrote an opera with the same title.
When Gideon Mantell was growing up in Sussex, the rocky strata around his home were rich in fossils of oyster-like shellfish along with ammonites and belemnites, both of which we now know had swum by jet propulsion like cuttlefish. There was little surprise at the sight of those fossils among the village folk who discovered them. Clearly, they were further evidence substantiating the biblical descriptions of the flood. The shellfish were believed to have been deposited during that inundation, while the coiled shells of ammonites were regarded as serpents that had been turned to stone and the pointed belemnite fossils were taken to be thunderbolts. Collecting these fossilized remains was a popular hobby among youngsters, and young Gideon’s enthusiasms were triggered by the discovery of an exquisite ammonite fossil when he was about 12 years old. Even though palæontology was a word yet to be coined, the collecting of fossils now had a term: oryctology. It is now forgotten and absent from most dictionaries (it has no page in Wikipedia), having originated from the Greek oryktos meaning ‘formed’. And so, by the time Gideon was grown, he was already a seasoned oryctologist.11
It was Mantell’s desire to become a physician that took him to St Bart’s Hospital, where his collecting in the field was replaced with the purchasing of fossils from London dealers including Joseph Stutchbury. Many of the doctors at Bart’s were fascinated by fossils, including the celebrated anatomist John Hunter, and many of those doctors simply purchased curiosities from dealers. In 1790 Hunter wrote a revolutionary account of fossils. Wisely, he proposed that the layers of marine fossils he observed had not resulted from the biblical accounts of a flood, and he concluded: ‘Many retain some of their form for many thousand years …’12
By this time, the way in which layers of rock were laid down in succession had become a fashionable subject for study in Germany. First to write authoritatively on the subject was a mineralogist born in 1714, Johann Gottlob Lehmann. He studied at Wittenberg and was subsequently invited by the Russian Academy of Sciences to move to St. Petersburg and expand his work. Rocky strata seemed to him amenable to serious scientific study, and he realized that they must have been laid down in strict order. In one mining area he identified more than 20 strata, which he called Flötzgebirge, and he soon realized that studying the sequence could perhaps allow prospectors to locate mineral-bearing strata. He concluded that this could be a key to the discovery of vast mineral riches.13
The idea was taken up by Abraham Werner, a young mineralogist who had studied at Freiburg, Saxony, and Leipzig. What a curious man was this – sensibly enough, he taught students that rocks were laid down in an orderly fashion, the study of which could help to ascertain where minerals would lie; but, although he never travelled, he confidently concluded that the sequences he observed in Saxony were representative of those everywhere else on Earth, and he decided that volcanoes resulted from the combustion of coal measures deep below the ground. He had a captivating and charming manner. His students hung on every word. He was only 36 when he published a definitive analysis on a classification of mountain ranges that quickly became essential reading for all budding geologists.14
One person who bought the book when it appeared was Alexander von Humboldt, a brilliant explorer and naturalist; he was the younger brother of the Prussian linguist and philosopher Wilhelm von Humboldt, and studied mineralogy and geology under Abraham Werner at the School of Mines in Freiburg, Saxony. Alexander von Humboldt bequeathed to us the most familiar geological period of all – the Jurassic. This was the name he gave to an important set of limestone strata that Werner had omitted from his book. This characteristic pale limestone was observed by Humboldt in the Jura mountains, so in 1795 he called it Jurakalk. From this, the term ‘Jurassic’ was soon to emerge. Now we know that this period extended from 201.3 to 145 million years ago, and was an era populated by gigantic sauropod dinosaurs. Alexander von Humboldt became widely admired and internationally famous. He was elected a foreign member of the Royal Society in England and the Royal Academy of Sciences in Sweden, while in the U.S. he was showered with honours, being elected a foreign member of the American Academy of Arts and Sciences, a member of the New York Historical Society, the American Antiquarian Society and the American Ethnological Society. Thomas Jefferson described him as the most important scientist he had ever encountered. Although Humboldt has named for us one of the best-known eras in the whole of palæontology, he did little research in that field and never studied fossil animals. But he did write about prehistoric crocodile tracks in samples of Buntsandstein rock that he discovered in 1834. He thought