Collins New Naturalist Library. Philip Chapman
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the classical Avernus and poetical descent into the infernal regions.”
The north-country clergyman John Hutton stands out among the ‘curious travellers’ as someone who developed a genuine interest in caves. His A Tour to the Caves in the environs of Ingleborough and Settle (in various editions from 1780 onwards) contained descriptions of some two dozen caves and potholes and was the first book in Britain, and one of the first in the world, whose main purpose was to describe the natural history of caves. In spite of his liberal use of Gothic adjectives such as “horrid”, “dreadful” and “terrible”, a real enthusiasm for his subject comes through, and in the two later editions of his book he added a section entitled “conclusions of a philosophic nature”, in which he discusses limestone geology, cavern formation and hydrology. Some of his views, particularly those on the springs and underground streams of the area, were farsighted, although others seem laughably quaint in the light of modern science. It is interesting for the modern reader to note the touchstone against which he measured his own ideas:
“I think I may say without presumption, that my theory is conformable to events as related by Moses; and my reasoning agreeable to the philosophical principles of Sir Isaac Newton, where they could be introduced.”
The early 19th century boom in natural science, when it spread to caves, focussed initially on two fields of research which Hutton had completely overlooked – namely palaeontology and archaeology. Deposits of bones had been known from caves in mainland Europe at least as far back as the 16th century, when speculation about their nature had inclined, as might be expected, to the fantastic. Some were considered to be dragon bones, while others – the sub-fossil tusks of elephants or mammoths, known as ‘unicorn horn’ – were greatly prized for their reputed medicinal properties. Quite an industry sprang up around such deposits, and their discoverers or the owners of the caves could become rich on the proceeds.
The Victorian naturalists were the first to appreciate the antiquity of cave bone deposits and their value as a geological record of Britain’s past. The best known of the early cave excavators was Dean Buckland, who plundered cave deposits throughout the country in the 1820s. In the interpretation of his results he was limited by the thinking of his day, but he recognized that many of the bones were from animals no longer present in Britain, and in some cases from animals that no longer existed at all. He was the first to suggest that the explanation for the accumulation of fossil bones in some caves might be that in the distant past hyaenas had used the caves as dens and dragged the carcasses of animals into them. Buckland also made the first find of an Old Stone Age human burial, the ‘Red Lady of Paviland’ found in Goat Hole on the Gower coast, so-called because her body had been anointed with ochre before burial.
Fig. 1.4 Gough’s Cave digging in early 1935, first published in Bristol Evening World, 1 Feb 1935. (Trevor Shaw collection, courtesy of Cheddar Caves Ltd.)
In the 1830s, Schmerling recognized that the remains of humans and of extinct mammals found together in the same deposits in Belgium were of the same age. It was not, however, until later in the century, that the work of William Pengelly and Boyd Dawkins and their colleagues established that these remains dated back thousands of years to the Ice Ages of the Pleistocene era, when cave-dwelling people shared our familiar countryside with a fearsome array of giant animals, including cave bears, hyaenas, woolly mammoth, bison, aurochs and woolly rhinoceros. Excavation in caves has, of course, continued to the present day, and cave sites worldwide have now yielded material which has helped to shape our understanding of human evolution and the birth of our culture.
The systematic exploration, documentation and commercial exploitation of caves was already underway in China many centuries before miners and natural historians first began to measure and record details of our European cave systems in a scientific way. One of the first of this breed of explorers in Britain was John Beaumont, a 17th century Somerset surgeon and an amateur student of mining and geology. When in 1674 lead miners excavating a shaft in the Mendip Hills accidentally breached a natural underground chamber, Beaumont hastened to the site and hired six miners to accompany him into the cave. Carrying candles, the company descended the 18 m shaft to the first chamber, which Beaumont proceeded to measure: it was 73 m long, two metres wide and nine metres high. “The floor of it is full of loose rocks,” wrote Beaumont in his subsequent report to the Royal Society, “its roof is firmly vaulted with limestone rocks, having flowers of all colours hanging from them which present a most beautiful object to the eye.” The intrepid surgeon then led a 100 m crawl through a further low passage which opened into the side of a second chamber, so vast, Beaumont reported, that “by the light of our candles we could not fully discern the roof, floor, nor sides of it.” The miners, accustomed as they were to the underground, could not be persuaded to enter this chasm, even for double pay. So Beaumont went down himself:
Fig. 1.5 Interior Chamber of Cox’s Stalactite Cavern, Cheddar, Somersetshire. Lithograph by Newman & Co. London; pub. S. Cox, Cheddar about 1850. (Courtesy of Trevor Shaw)
“I fastened a cord about me, and ordered them to let me down gently. But being down about two fathom I found the rocks to bear away, so that I could touch nothing to guide myself by, and the rope began to turn round very fast, whereupon I ordered the miners to let me down as quick as they could.”
He landed dizzy but safe 21 m below, on the floor of a cavern 35 m in diameter and nearly 37 m high within which he found large veins of lead ore. Surprisingly, Beaumont’s account failed to stimulate much curiosity about caves in scientific circles, and after a brief flurry of lead mining, the cave, known as Lamb Leer, was abandoned; its entrance shaft eventually collapsed and the sealed-off chamber was virtually forgotten for two centuries.
The rediscovery of Beaumont’s long-lost Lamb Leer cave took place in 1879, the same year that a young French law student, Edouard-Alfred Martel, made his first visit to the famous Adelsberg Cave in Slovenia (which was then part of Austria, but since World War II has reverted to its local name of Postojna Jama). Martel was completely enthralled, and in 1883 began to devote all his vacation time to cave explorations in the Causses of southwestern France. What set him apart from previous cave explorers, was his meticulous preparations and his systematic recording of all aspects of the caves he explored, combined with a tremendous physical ability and courage. His speciality was deep vertical pits, and in 1889 he successfully negotiated the 213 m vertical entrance shaft of the Rabanel pothole north-west of Marseilles – an outstanding feat given the equipment then available.
To calculate a pit’s depth, he would read the barometric pressure at the bottom and compare it with the surface pressure. He measured the horizontal dimensions of each newly-discovered chamber with a metal tape, drawing a sketch of the cave as he worked. Roof heights were calculated with an ingenious contraption: after attaching a silk thread to a small paper balloon, he would suspend an alcohol-soaked sponge beneath it, light the sponge, and measure off the length of thread carried aloft by the miniature hot-air balloon. Martel also habitually recorded subterranean air and water temperatures, finding variations with depth and season, and amassed whole volumes about cave geology, hydrology, meteorology and flora and fauna. But perhaps his greatest contribution to cave science was his research on how subterranean water circulates – a study prompted by his own bout with ptomaine poisoning, contracted from drinking spring water in 1891. After recovering from the illness, he traced the spring’s source using fluorescein dye introduced to nearby sink holes. Descending the appropriate pit, he found the putrefying carcass of a dead calf that had contaminated the spring with what he wryly termed “veal bouillon”. Further study allowed him to distinguish between “true springs”, fed by diffuse circulation of rainwater, cleaned and filtered by its passage through soil and rocks, and “false springs” fed by a rapid flow from sinkholes via cave passages too large to filter out impurities. Martel’s subsequent campaigning for stricter control of sources of drinking water eventually led