Discovering the ammonite aroused different emotions from those that lit up my day in the cinema on Oxford Street. I could never own a dinosaur, I could only wonder from afar. The Natural History Museum had (and still has) a splendid gallery of marine reptiles – ichthyosaurs and plesiosaurs, several of them collected in the nineteenth century by the pioneering woman scientist, Mary Anning. A number of these specimens were discovered at Lyme Regis, a little further west along the Dorset coast from Burton Bradstock. The most I could expect to find of one of these magnificent beasts would be a vertebra or two. The ammonite was different. It was a whole specimen, and I could add others of its kind to my collection. The commonest fossils are invariably those of smaller marine creatures whose shells were entombed in sediment after they died. They are the pawns on the chessboard of life. Humble they may be, but they constitute a wonderful array of different kinds of animals: clams, snails, sea urchins, brachiopods, belemnites, corals, trilobites. I wondered if there was a specialist for every one of them in the Natural History Museum. I would learn all their names; I would master the past! Fossils would become my next target: I would discover where they were hiding in cliffs and quarries and ditches. Who knows what I might turn up?
There is a common misconception that fossils are uncommon. My first ammonite seemed to me an object of great significance, a rarity as precious as a Roman gold coin. When I began seriously to look for fossils I discovered that there were special localities where they were rather numerous. I soon recognised that a collection could sample a whole ancient habitat, and give a feel for life on sea floors that had long vanished into deep history. I could wade in the warm waters of a Jurassic reef, or I could swim alongside the ammonites. I could even devise my own pictures to replace the old images in The Children’s Encyclopedia. The charisma of collecting increased in direct proportion to the age of the fossils; the more ancient, the more exotic. I soon learned the geological periods in their proper order, the litany of geological time. Their names seemed romantic and evocative, and the older ones had a special magic. Cambrian, Ordovician, and Silurian had an irresistible allure, an alien strangeness. My new geological map of Britain was easily read as a diagram to predict what fossils I could find in a particular stratum, as the rock formations were plotted out in colour describing bands across the land. Some of the colours on the modern map dated all the way back to the first geological map made by William Smith in 1815, like the green that signified Cretaceous chalk. Green it has remained for two centuries. I still sometimes feel that at some subliminal level chalk must be green, even though I know perfectly well it is as white as … chalk.
My father fished pure chalk streams, and on Woodspeen Farm there was an old pit dug down into the white rock beneath, probably to make quicklime to ‘sweeten’ the soil – part of the process Robinson had outlined in my first chemistry book. It was an obvious place for me to commence fossicking for fossils. Old chalk pits were rather common after the war, a legacy of a time before chemicals were bought in for agricultural purposes. Picking over the pallid lumps in the quarry I soon learned to recognise flints within the chalk; they were part and parcel of the same sediments – hard silica, white outside and black inside, and so inert as to be practically immortal. Sometimes flint nodules resembled a baby’s foot or a small head, but they were put there specially to mislead the novice, for these were nothing more than ‘pseudofossils’, fortuitous shapes designed to fool the unwary. Flints of whatever form survive indefinitely to frustrate gardeners with their unassailable obduracy. Then something different caught my eye, partly sticking out of a lump of chalk, rounded and the size of a large coin, but with a suggestion of pink to it – a fossil! I carried the chalk cobble home to see if I could extract the rest of the fossil from its rocky hiding place. The good thing about chalk is that it is a very soft type of limestone that can even be cut with a sharp knife. I tapped off small chunks that were obviously not part of the fossil, and then carefully pared off layers of the chalk matrix until I was close to the specimen that had lain hidden for so long. When I felt I was in danger of damaging whatever-it-was I stopped carving and started scrubbing. An old toothbrush steeped in water slowly scraped off the chalk, but the bristles were not hard enough to damage any entombed fossil. Gradually, a shape emerged, a heart shape, and as more of the chalk wore away I made out five shallow grooves excavated into the highest part of my find. The opposite side of the fossil was flattened. It was a beautiful sea urchin. I found out later that the scientific name of the heart urchin was Micraster, which means ‘small star’, presumably referring to the five grooves making that rayed pattern. Under a magnifying glass I saw that the whole animal was made up of calcite plates that fitted together as perfectly as a mosaic, except for two round holes that I learned subsequently were the urchin’s mouth (on the bottom) and the anus (at the end). The whole urchin would have originally been covered with hairy spines, almost a fur. The glass revealed something else: there were smaller fossils perched upon my fossil: the tube of a small worm, and a branching colony of tiny bryozoans.[2] These would have settled on the dead urchin to filter out tiny organic particles from the seawater that washed over it. My sea urchin housed a whole community! The fossil fitted neatly into the palm of my hand and I cradled it as if it were some kind of talisman. I felt that it had crossed 90 million years especially to be discovered by me, fossil boy.
Fossils of sea urchins were common in the chalk at the edge of the Berkshire Downs.
The collection had begun. I discovered more fossils in the chalk as I explored other quarries nearby. Two sea urchins other than Micraster found a place in the shoebox that first housed my finds; one was a neat cone, the other larger and shaped rather like a round bun. The ‘bun’ was cast in flint, but it was no pseudofossil – it looked as if the inside of the sea urchin had been filled up with flint, as now there was none of the original shell remaining. I had picked it up in a field where it must have been brought up by the plough. Fossil urchins like this were long known as ‘shepherd’s crowns’, so they must have been spotted by farm hands who knew nothing of their true antiquity. They might well have believed that the ‘crowns’ were placed in the fields by mischievous sprites. These flinty urchins were much tougher than the original fossils, so they survived erosion and ploughing to pop up from the ground like treasure to puzzle passing shepherds. If the sea urchins were the stars of the collection, there were also simple clams that looked not very different from oysters and scallops, a small ammonite that sported lumps as well as ribs, and rounded brachiopods about the size of boiled sweets. All these discoveries were made of the same shell material – calcium carbonate, chemically the same as chalk itself (CaCO3), the favoured building material for the majority of marine animals. But the quarry was to yield up something utterly different. Out of a lump of chalk a shining, sharp blade protruded – I could have cut myself with it. It was a shark’s tooth. The brilliant lustre on the tooth was proof that it was made of bone rather than calcite. It was not difficult to dig out; it was larger than my thumbnail and just the shape you would expect from one of the ranks of teeth that fill the mouth of Jaws. It was going to displace Micraster as the favourite chalk discovery. I began to sketch a picture of the chalk sea in my head: sea urchins, brachiopods and clams on the soft sea floor, a shark cruising above in search of fishes. What I could not see was that all the white stuff of the chalk itself comprised uncountable millions of tiny fossils of planktonic, single-celled organisms. It required an electron microscope to explore their secrets.
As the collection grew I needed names for my finds, as well as a larger cabinet to house it. There was something rather grand about Latin names, and few fossils had common ones. I was not intimidated by classical names because I was taught Latin by Mr Saunders, who drilled his class with such efficiency that nearly everyone got 90%. We learned the translation of Caesar’s Gallic Wars (Book 3) by heart, so that when it came to our O level examinations we just had to recognise a few prompts to write out
the whole passage in perfect English. One phrase that remains with me is that Caesar’s navy sails were ‘lightly tanned and dressed with alum’, for which information I have yet to find a use. Only Smithers misidentified the prompt and wrote out a completely different passage that bore no relation to the Latin original. Few fossil names were as obvious as Parkinsonia. Some were real mouthfuls: my heart urchin was probably Micraster cortestudinarium, and I confess to a certain braggadocio when I trotted out the name to impress anyone who was interested, and many more who were not. I realised that the complicated species name referred to a heart (cor) and a tortoise (testudo) so it was not implausible as a description. I had my first inkling that the Latin (I should say scientific) names served as an international language and provided a rational way to deal with the immense diversity of life.
The Geological Museum was next to the Natural History Museum on Exhibition Road in South Kensington. It was much less visited, except by me. The upper floors had systematic collections of British fossils laid out according to their age and locality. Specimens were displayed in old-fashioned cases with glass tops, just ranks of examples with their geological age and scientific name on the label. Southern England would have a case or two with chalk fossils in the Cretaceous section, another couple of cases with the typical fossils from the Inferior Oolite as part of the Jurassic section. This particular case held a much better specimen of the ammonite Parkinsonia parkinsoni than my founding fossil. The display was fairly comprehensive, and an enthusiast could pore over the cases almost undisturbed. There was nothing here to get the warders in a tizzy, no ‘Do not touch’ notices to be disobeyed. I was often the only person in the gallery, and certainly the youngest. I would take out a fossil I had brought with me to match it with one on display. In the chalk section: my pyramidal sea urchin was like Conulus albogalerus, my shepherd’s crown was a dead ringer for Echinocorys scutata. One of my big clams was certainly an Inoceramus, but I could not decide which species exactly matched mine. The brachiopods were a more varied group than I had realised: I was learning more precise observation and more refined discrimination. I carried a notebook to record the details so that I would be able to update the labels in my own collection. I was as happy as could be. In the early 1960s the Natural History Museum produced handbooks with good drawings of fossils to supplement my visits[3] but there was no substitute for looking at the real thing – and besides there was always the chance of finding a species which was not included in the handbook. While my contemporaries played Saturday football in Pitshanger Park I was the solitary child in the Geological Museum. My mother must have thought that I was a curious boy.
The display cases have all gone. They began to seem old-fashioned, and they were not as attractive to the average visitor as new exhibits with friendly text offering full explanations, and plenty of special effects. The Story of the Earth appeared in the Geological Museum in the early 1970s and became a great success, because it explained the advances in geological understanding of our home planet since the advent of plate tectonics; it also featured earthquakes and erupting volcanoes. The stratigraphic collection of fossils on display was doomed, and the fine examples of ammonites and all the other invertebrate shells mostly went back into storage in the vaults. Nowadays, there are other ways for curious children to identify their specimens. But if there were such things as ghosts, after the visitors have left for the day I could imagine hearing the footfall of a young wraith walking back and forth seeking the cabinets that once held such a special charm. The former Geological Museum is now just part of the Natural History Museum – the Earth Galleries, or the Red Zone. Schoolchildren flock through it on the way to the dinosaurs.
* * *
I was extraordinarily lucky to be able to study geology as a subject while I was at Ealing Grammar School for Boys. The geography master proved to be a geologist manqué. He was one of those rare teachers that almost every student recalls with gratitude and respect. K. E. Williams was known to most of his students as ‘Kew’; for me, he always remained Mr Williams. He was a small Welshman with a long, pointy chin and a ready smile. He never had to raise his voice to control a classroom – it just seemed to happen. Some of his colleagues used tricks to achieve the same end, the deployment of sarcasm being a popular ruse. To a talkative pupil such a master might say, meaningfully: ‘I am sure you would wish to share your brilliant insights, Smithers, with the rest of the class.’ Smithers blushed, and mumbled in embarrassment as silence fell. Mr Williams just effortlessly interested his audience in the Nile Delta, the crops of the Mediterranean region, or the climate of central Spain. He hardly ever set homework, and almost all his students passed the geography examinations with distinction. His real passion was geology. He had completed a geological master’s degree at the University of Aberystwyth. He had published a scientific paper based upon his thesis in the Geological Magazine in May 1927: ‘The glacial drifts of western Cardiganshire’. The title may not resound mightily, but it was his contribution to scholarship and he was proud of it, shyly producing a ‘reprint’ of the article for his small geology class to admire. I felt a similar diffidence when I published my first article in what our trade calls a ‘learned journal’. Mr Williams had amassed a select teaching collection of fossils that included some of the species I had discovered. This was where I handled my first trilobite.
Day trips into the field in southern England took us over the chalk downs and across the Weald. It was a happy release from the routine of school life; we felt as if we belonged to a small and exclusive club that was allowed to have fun – but we were also learning. This was better than sitting in the physics laboratory fiddling with a Wheatstone bridge! Mr Williams explained how the sequence of strata controlled the landscape. The downs rose up to make the high ground, and the slopes near Box Hill were dark with native yew and box trees, while white gashes marked old quarries that revealed the chalk beneath. I wanted to stop to find another Micraster sea urchin. Near Dorking we inspected the Silent Pool; water as pure and clean as in any spa bubbled up from a spring on the line where permeable chalk met the impermeable clay beneath. This Gault clay then made a poorly drained valley that was tracked by the main routes and rivers. It could all be followed logically on the geological map. In the distance the hard ridge of the Lower Greensand rose up at Leith Hill to match the downs in elevation, and we drove to examine it along narrow sunken lanes that had been eroded by centuries of ox carts struggling up steep inclines. Dark green straps of hart’s tongue ferns lined the route. From the top of the sandstone scarp the view south over the Weald showed another broad strip of deeply wooded low clay ground with misty hills in the distance where yet more resistant sandstones came into outcrop. Hill and vale followed the bidding of the rocks, and geology provided the key to reading the landscape. Even the older houses we passed reflected the underlying strata: flint with brick corners on the chalk; clay bricks in the poorly drained valleys, timber houses in the wooded Weald. In future I would be wearing geological glasses on my journeys around Britain. Mr Williams had helped to change my vision of my homeland.[4]
When I was fourteen we had a family holiday (minus Father, of course) to St David’s, Pembrokeshire, the smallest cathedral city in Britain, on the south-western tip of Wales. By now, we had graduated from the caravan to staying in a spartan guesthouse. The peninsula on which St David’s is perched is rather flat and featureless, and Mr Williams would doubtless have described it as an uplifted peneplain. The city itself was (and is) both ancient and charming, running down the hill towards the old cathedral. Most buildings are rather modest, and almost everything is built from the tough purplish or green sandstone that underlies much of the tip of this small peninsula. It is geologically one of the most ancient areas south of the Highlands of Scotland; the streets of St David’s have grown from their rocky foundations and feel at ease with their surroundings. The result is a pleasing little city with nothing that seems out of place. The square-towered cathedral is tucked in a hollow bac
ked by open countryside. It manages to be hard to see until the visitor stumbles right upon it, as if it were crouching discreetly. Ruins of a large and opulent Bishop’s Palace add to the impression of an important medieval centre for English church and state when most of Wales was still inaccessible.
The glory of St David’s is its coastline, where ancient rocks abut a fierce sea. Inaccessible bays are backed by mighty vertical cliffs that have been fretted by thousands of years of erosion. Clefts in the rock face make narrow caves into which the waters suck and belch. The strata making up the cliffs have been mangled by the profound earth movements that elevated the Caledonian mountain chain about 400 million years ago: nothing here remains horizontal, and the rock beds are often twisted tortuously into folds, or abruptly terminated by great faults that cut vertically as if to ignore the geology altogether. Different colours were juxtaposed when the earth’s crust was sliced into these chunks: Caerfai Bay is backed by bright red shale; Solva displays black slaty rocks; massive, subtly coloured sandstones define promontories. Most implacable of all is St David’s Head – a huge mass that welled up as hot magma cooled to make an igneous intrusion that offers endless resistance to the relentless breakers. These rocks have suffered deeply in the past and face an onslaught today; the fine spray thrown skywards as another wave crashes ashore is like the exhalation of some enormous whale. The sea picks at the unyielding rock atom by atom.
On the wall of the guest house an old map illustrated the geology of the St David’s area. The rocks had all the glamour of extreme antiquity, for here were the Cambrian and Ordovician strata I had long sought, with their outcrops clearly plotted, and even notes on what to expect in the way of fossils. ‘Cambrian trilobites here’ was marked on a narrow bay called Porth-y-rhaw; north of St David’s Head ‘Ordovician graptolites abundant’ was printed next to Abereiddy Bay. All I wanted to do was to get to these places to see what I could find. My holiday was about to become my destiny. My sister tells me that it rained a lot of the time, which is not unknown in Wales, but my enthusiasm was more effective in buoying my spirits than any raincoat. All I needed was to be dropped off, and picked up before dark. My mother and sister went off in the car in search of ponies to ride, or to find somewhere to get dry. Porth-y-rhaw hardly qualified as a bay, being more like a diminutive Cornish cove, a narrow cleft in the implacable coastline, with a beach of rounded boulders through which a small stream found its way to the sea. Short turf and gorse covered the higher ground. Dark-coloured hard shales that had been tipped nearly vertical were accessible on the left-hand side of the inlet as I faced out to sea, but the waves broke dangerously close. When I jumped to avoid getting wet I glanced up at the cliff and there was the trilobite – and not just any trilobite, but a huge one, at least a foot long. It was out of reach on the steep rock face, proof if any were needed of the tectonics that had tipped everything upwards. Its surface was wrinkled and cracked, but the trilobite’s head, and thorax of many segments could easily be made out even though it was the same colour as the enclosing shale. It had suffered but not been obliterated, a survivor from the Cambrian period, a messenger from 500 million years ago. When I learned it was called Paradoxides, it seemed to be an appropriate name: it indeed appeared to be a paradox that such an ancient animal could be so complex, and more so than Parkinsonia to my naïve eye. I wanted to find one of these trilobites for myself, but there was no way I could extract a large enough piece of the hard rock. My more modest efforts were not entirely in vain. Once I had learned to break the rock with my hammer along the plane of the ancient sea floor I recovered several tiny trilobites with short thoraces (Eodiscus punctatus) just sitting on the surface of the broken rock exactly as they must have died in Cambrian times. Pride of place went to another trilobite, the flanks of whose body seemed to be covered with ramifying veins. I wrapped my finds safely in newspaper so that they could not scratch one another, and this was my first collection of the animals I would spend many years studying. It was a day well spent. When I got back to our lodgings I unwrapped the best specimens trying to imagine the seas in which they lived, taking a dive back through time and space to a world that was waiting to be explored.
A Curious Boy Page 10
