Too Big to Walk. Brian J. Ford
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This substantiated that animals could become extinct and that skeletons of preserved carcasses were similar to the fossilized remains that were excavated elsewhere. Cuvier documented his fossil skeletons, and in 1812 he published his research, serving to dignify the study of fossils. The Maastricht fossil was a lizard as big as a crocodile, and the pterodactyl he distinguished from birds or bats, insisting it was a flying reptile. These were exciting conclusions that were already causing consternation and interest among scientists and writers. It was now clear that there had been eras when strange and unfamiliar creatures roamed the Earth32 and in Bleak House, which Charles Dickens started writing in 1852, he said it would be ‘wonderful to meet a Megalosaurus, forty feet long or so, waddling like an elephantine lizard up Holborn Hill.’
The resonances of these fossils in present-day thinking were alluded to by Reverend Charles Kingsley, when he published a serialized story in MacMillan’s Magazine each month from August 1862 through to March 1863.
French palæontologist Louis Figuier published his La terre avant le deluge (the world before the flood) in 1863 and it became immensely popular. His illustrator, Edouard Riou, portrayed an Iguanodon and a Megalosaurus fighting with each other.
Did not learned men, too, hold, till within the last twenty-five years, that a flying dragon was an impossible monster? And do we not now know that there are hundreds of them found fossil up and down the world? People call them Pterodactyles: but that is only because they are ashamed to call them flying dragons, after denying so long that flying dragons could exist.
The stories were popular, and were brought together into a single volume in 1863. As a classical moralistic tale for children it has remained in print ever since.33
What was becoming increasingly apparent was the curious consistency in the way rocks had been laid down. This new science began with Friedrich August von Alberti, born in 1795, when he attended a military academy in Stuttgart and took up geology as a hobby. Later he took up employment in the salt production plant at Rottweil, an exquisite medieval town that has still changed little since the 1500s. (This is the place after which Rottweiler dogs are named; they are believed to be the direct descendants of the military breed that Roman soldiers brought during the invasions by the Caesars.) In 1815 Alberti came to recognize the occurrence of three characteristic strata composed of sedimentary deposits. He regularly found three distinct layers: one of red sandstone, capped by chalk, and succeeded by black shales. They occur throughout Germany and were later found to extend across the whole of northwest Europe. In each he found the same characteristic types of fossils and, from the Latin trias (meaning trio), he coined the term Triassic.34 We can now date this geological period as extending from 252.17 to 201.3 million years ago, for this is when the first dinosaurs appeared. The Jurassic period starts where the Triassic leaves off, and that is when dinosaurs first reached their enormous size.
Shortly after Alberti had coined the term Triassic, Jean Baptiste Julien d’Omalius d’Halloy in Belgium recognized the Cretaceous. Born in 1783 in Liège (now in Belgium, but then in the Austrian Netherlands), d’Halloy was sent by his wealthy family to study literature and the classics in Paris. He wanted none of it – geology became his consuming passion. He attended many lectures given by the distinguished naturalists and geologists and he learned everything he could from Georges Cuvier. He loved studying the rocky structure of France, and being of independent means he could travel as widely as he wished. In 1808 he published a learned paper entitled ‘Essai sur la géologie du Nord de la France’ in the Journal des Mines, an extraordinarily wide-ranging subject for someone working independently. It was in this paper that he recognized the distinct nature of coal-bearing strata, which he named Terrain Bituminifère. The name did not gain common currency, but it was the first time that the coal measures were identified as providing a key to an earlier era of the Earth’s history. He also recognized the era of chalk formation and drew sections showing its extent; this he named the Terrain Crétacé, and it was soon recognized in English as the Cretaceous period. He is estimated to have travelled more than 15,000 miles (24,000 km) across France, and he published an immense range of textbooks on geology, all written with clarity and precision, and including some of the first illustrations of the sequence of geological strata.35
Meanwhile, in England, William Coneybeare and William Phillips – both keen amateur geologists – had also concluded that the era of coal-bearing strata must have been confined to one period of time, because of the similar fossil plants that they all contained. Their conclusion substantiated d’Halloy’s designation of his Terrain Bituminifère. This had been an era of gigantic cycads, massive stands of horse-tail Equisetum plants, and huge conifers like today’s monkey-puzzle tree Araucaria. The two English friends realized that this had been an age of swampy forests and – because of the undeniable fact that this was the era that gave us coal – in 1822 they decided to call it the Carboniferous age, from the Latin carbō (coal) and ferō (bearing).36 Today we know this geological period extended from 358.9 to 298.9 million years ago.
Recognizing these great periods – the Jurassic and Triassic, Carboniferous and Cretaceous – had now given palæontologists a greater understanding of the ages through which the Earth had passed. Our present-day countryside reveals the tortured history of churning cliffs and the weathered remains of towering mountains that have resulted from the collisions between continents over millions of years. Now eroded and reduced in stature, the mountain ranges have become rolling hills and the cliffs are cut through like a layered cake so that the æons of prehistory can be seen in strata that stretch back in time. These reveal a timeline of the way that masses of land drifted across the globe, showing us how places like North America and Europe started in the southern Arctic wastes and slowly headed north, where they now extend up towards the northern latitudes of ice and snow. Once, today’s western nations sat at the equator, and the sandy deserts from that time are bequeathed to us as sandstone strata. Later, the land was covered with huge swampy stands of conifers and cycad trees as we drifted past the tropics, and we can see them still in the coal measures. The drifting still goes on. As new rocks are spewed up from a massive split in the Earth’s crust that runs down the middle of the Atlantic, the mid-Atlantic ridge, continental masses on either side are still being forced apart. America and Europe are moving away from each other at the same speed as your nails grow. Clip a couple of millimetres from your toenail and reflect on the fact that the flying distance between New York and London has increased by precisely the same amount.
Some of the rocky strata tell a powerful story of a prehistoric world dominated by massive monsters and strange landscapes. At Kimmeridge Bay in Dorset, for example, you find oil shales from which crude oil seeps just as it does in the world’s greatest petrochemical producing nations. Indeed, there is a nodding donkey oil pump at Kimmeridge, just like those in the American oilfields. Those shale beds formed during the late Jurassic, between 157.3 and 152.1 million years ago, and from them the most beautiful fossils sometimes emerge – bony skeletons of strange swimming plesiosaurs and forbidding dinosaurs. They have been collected as curiosities for centuries. The leading present-day collector is Steve Etches, a plumber who made his living repairing and installing bathroom and kitchen appliances around Kimmeridge. At least, that was in his day job; every moment of his spare time is spent hunting for fossils in the nearby rocky cliffs. He has a keen eye and can spot a fossil when most people see nothing but stone, and his home has been extended to become a private museum. Etches has collected more than 2,000 specimens over the past 35 years. Palæontologists the world over respect his achievements; indeed, in October 2016 the Museum of Jurassic Marine Life was opened a few yards from his home to display the highlights of his collection. It is an exquisite stone building, part of which is the village hall, while the rest is a museum and a laboratory which Etches can enter through a private door