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The HMS Challenger Expedition, 1872-1876
From: The Natural History Museum
| By:
Tony Rice |
EDITOR'S INTRODUCTION |
The Challenger's 68,890-nautical-mile expedition, organised by the biologists William Benjamin Carter and Charles Wyville Thomson in 1872, witnessed the birth of oceanography as it is known today. Tony Rice explains how the voyage provided positive proof that life really did exist on the deep-sea bed. Scientists were also able for the first time to identify sediment material as extraterrestrial dust from comets and asteroids. |
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| The HMS Challenger. | |
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 y the middle of the 19th century all of the earth's main landmasses, and most of the minor ones, had been "discovered" and their coastlines, at least, pretty well surveyed. But despite more than two centuries of fairly intensive navigation all over the world's ocean by vessels from many nations, almost nothing was known of the nature of the deep seas beyond a depth of a few tens of metres. Even the basic depths of the great ocean basins were still a mystery, while it was commonly believed that the utter darkness, high pressures and intense cold assumed to characterise the deeper layers meant that they would be totally lifeless. In the 1850s and 1860s, however, a number of factors came together to change all this. |
 First, developments in submarine telegraphy and mounting pressure to lay cables between the continents generated a demand for accurate knowledge of the shape and nature of the deep-sea floor. Second, some tantalising, but inconclusive, new pieces of information suggested that the idea of a lifeless deep sea might be erroneous. Moreover, some of the animals found in early deep hauls were what we would now call "living fossils" and adherents of the evolutionary process proposed in Charles Darwin's recently published On the Origin of Species thought that the deep ocean might hold many more. Clearly there were strong commercial and philosophical arguments for studying the deep oceans. And so it was that on 21 December 1872, a Royal Naval corvette, HMS Challenger, sailed from Portsmouth at the beginning of a three-and-a-half-year voyage of scientific exploration which was to become the most famous expedition of its kind ever undertaken. It is often considered to represent the birth of oceanography, the science of the sea, for it was an absolute first. Never before had any nation despatched a major expedition with the express purpose of studying the physics, chemistry, geology and, particularly, biology of the deep ocean. At a total cost to the UK Treasury of almost £200,000 (well over £10 million today) it was also the world's first example of "big science," for nothing like this amount had ever been spent on a single scientific undertaking before. |
The voyage was the brainchild of two civilian biologists, Professor William Benjamin Carpenter (1813-85) from the University of London and Charles Wyville Thomson (1830-82), Professor of Natural History in the University of Edinburgh. Like most other scientists of the day, until a few years before the Challenger Expedition Carpenter and Thomson had accepted the idea of a lifeless deep sea. But a series of short cruises on rather unsatisfactory naval ships around the British coasts between 1868 and 1870 had convinced them, correctly, that animal life would be found at all depths in the sea. These cruises also dispelled another myth, that the deep seas were universally filled with water at a temperature of about 4°C (40°F)--based on the erroneous assumption that, like fresh water, sea water has a maximum density at this temperature. As the preliminary cruises revealed, temperatures at the near-bottom of the ocean could be considerably lower or higher. But these results were based on a few observations in one corner of a single ocean. What was needed, Carpenter and Thomson reasoned, was a properly equipped global expedition to investigate the last great geographical unknown on earth. The audacious proposal was put to the Admiralty via the Royal Society and, with surprisingly little opposition, was accepted. |
The submission had come at an auspicious time. Britain was at the peak of her imperial power; Britannia unquestionably ruled the waves and British jingoism was alive and well. Consequently, many within the Admiralty, and outside, thought that Britain should lead the way in any innovative maritime undertaking. Moreover, while the Admiralty Hydrographic Office had been the world's finest surveying and chart-making institution for several decades, until recently its interest in the deep ocean had been limited. But the submarine telegraph companies were asking unanswerable questions about the deep-sea floor so that quite apart from the scientific arguments, the proposal had the backing of the Hydrographer, Admiral G. H. Richards. |
Within 18 months a ship had been selected, extensively refitted with purpose-built laboratories, civilian accommodation and winches, and supplied with tonnes of the latest equipment--including more than 400 kilometres (249 miles) of rope--for the extensive research programme. The ship's Captain was to be an experienced surveying officer, George Strong Nares (1831-1915), supported by a naval complement of about 225. The civilian scientific staff of six was headed by Thomson as chief scientist (at the age of 58, Carpenter had decided he was too old to participate) and included a Scottish chemist, John Young Buchanan, three zoologists: one English, Henry Nottidge Moseley; one Scottish-Canadian, John Murray; one German, Rudolf von Willimoes-Suhn; and a Swiss artist, Jean Jacques Wild. This was a curiously appropriate mix for the beginnings of a discipline which has been characterised ever since by international collaboration. |
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| Scientific dignitaries from the Royal Society, together with some of the expedition's scientists on board the Challenger at Sheerness in early December 1872. | |
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| A Moro Indian from Zamboanga, Mindanao. | |
After a short "shake down" period to check the sampling techniques, and brief calls at Lisbon and Tenerife, the work began in earnest on 15 February 1873, some 64 kilometres (40 miles) south of the Canaries and at a depth of 3,500 metres (11,483 feet). Here, the Challenger personnel worked what would be the first of many official "stations" or study sites dotting the world's oceans. By the time the ship returned to Spithead on Queen Victoria's 51st birthday on 21 May 1876, the Challenger had criss-crossed all of the major oceans other than the Indian, covering a total of 68,890 nautical miles, mostly under sail despite her 400 nominal horsepower coal-fired steam engine, coupled to a twin-blade propeller. She had spent more than half of the intervening days in harbour, providing her sailors and scientists with the opportunity for exotic port calls in North and South America, South Africa, Australia, New Zealand, Hong Kong, Japan and a series of Atlantic and Pacific islands. During these runs ashore the ship's officers and scientists made extensive zoological, botanical and ethnographic collections, and met all kinds of people, ranging from the King of Portugal and the Emperor of Japan to Fijian natives who had only recently given up cannibalism. Many of these events and views were documented by the official artist, Jean Jacques Wild. But many were also recorded photographically, because the Challenger Expedition seems to have been the first to routinely use this relatively new technology. Photography was, of course, still in its infancy and the long exposure times required made it quite unsuitable for action shots, for example of the scientists or sailors working on deck. But it was excellent for recording individuals or groups of people as well as distant views; indeed, one of the requirements in the expedition's official instructions was that: "Every opportunity should be taken of obtaining photographs of native races to one scale." Consequently, the resulting superb collection of photographs provides an historically important record of places and people in the late 19th century--including, probably, the very first photographs of Antarctic icebergs ever taken. |
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| Queen Charlotte of Tonga. | |
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| Specimens collected during the four-year voyage of the HMS Challenger. | |
But the Challenger's main work, of course, had been accomplished during her 713 days at sea when, every two or three days on average, she would stop and work one of her 362 official stations. At each one, the depth of water was measured and a small sample of the bottom sediment was collected. The water temperature at the surface, near the bottom and often at several intermediate depths, was measured and water samples collected for later chemical analysis. Finally, biological samples were obtained, always using a dredge or trawl dragged across the seabed and often also plankton nets to collect midwater animals down to about 1,500 metres (4,921 feet). Each time, the catch had to be carefully sorted, preserved, bottled, labelled, stored and meticulously documented. The speed and direction of the surface currents were also recorded fairly routinely while attempts to measure the shallow subsurface currents were made rather less regularly. |
During the course of the voyage, material was sent back from Bermuda, Halifax, the Cape, Sydney, Hong Kong and Japan. In his introduction to the scientific reports Thomson wrote that "... after the contents of the ship had been finally cleared out at Sheerness, we found, on mustering our stores, that they consisted of 563 cases, containing 2,270 large glass jars with specimens in spirit of wine, 1,749 smaller stoppered bottles, 1,860 glass tubes, and 176 tin cases, all with specimens in spirit; 180 tin cases with dried specimens; and 22 casks with specimens in brine." He adds that "... of upwards of 5,000 bottles and jars of different sizes sent from all parts of the world to be stored in Edinburgh, only about four were broken, and no specimens were lost from the spirit giving way." Despite the importance of these specimens, the mechanics of collecting, storing and recording them was tedious, as was the cataloguing of the endless measurements made at each of the stations. Even for most of the scientists the novelty wore off after the first few tens of stations, while several of the officers documented their boredom in their personal journals. It must have been much worse for the ordinary sailors who had to do all the hard physical work without the reward of a vested interest in the results. No wonder 61 of them deserted at the various port calls. |
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| Drawing by Jean Jacques Wild of a glass sponge, probably Euplectella suberea. Probably "reconstructed" from damaged specimens collected in deep water. | |
But it was the sheer routine that was the strength of the Challenger Expedition. Almost nothing accomplished from the ship was absolutely new, for the techniques employed were mainly tried and tested ones which had been used sporadically by ships of many nations. The significance of the Challenger was the intensity of the observations made, the global coverage and particularly the emphasis on very deep water. Her deepest sounding, at almost 8,200 metres (26,904 feet) in what later became known as the Challenger Deep in the south-western Pacific, was by far the deepest taken up to that time, at a site very close to where the current record depth--of a little over 11 kilometres (seven miles)--was measured. Similarly, her 25 successful dredgings at depths in excess of 4,500 metres (14,765 feet), and the deepest at 5,700 metres (18,701 feet), were totally unprecedented. |
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| Two specimens of the Venus's Flower Basket sponge, Euplectella aspergillum. | |
The resulting vast biological collections were shipped back periodically to Edinburgh to await the ship's return. For like all scientific undertakings, it was realised that the collections and the data would be of little value until they had been intensively studied and the results published. Accordingly, Thomson established a Challenger office in Edinburgh after the voyage to collate all the data, despatch the biological specimens to specialist scientists and supervise the publication of the resulting reports. This was to take much longer than the voyage itself, and after Thomson's death in 1882 the supervisory role was taken over by John Murray (1841-1914), one of the junior naturalists on the voyage but destined to become one of the most famous scientists of his day. It also turned out to be a much bigger task than had been originally envisaged. Thomson had estimated that the results would run to about 15 volumes to be published by the Stationery Office within about five years. In the event, the official reports ran to 50 large volumes with a total of 29,552 pages. The final two volumes appeared in 1895, 19 years after the end of the expedition. |
The preparation of the reports had also involved Thomson and subsequently Murray in a series of rows. Firstly, this was because the authorities of the British Museum thought they should receive the collections and organise the work on them, rather than Thomson in Edinburgh. Many also thought that only British scientists should work on the material, rather than the best scientists, irrespective of nationality, as Thomson wished. Thomson won, and the collections were sent to an international galaxy of experts from France, Germany, Italy, Belgium, Scandinavia and the United States, as well as from the UK. The specimens eventually went to The Natural History Museum in London, where they remain to this day. |
But the longest and most difficult battle was with the Treasury which was most unwilling to foot the increasingly large bill for the publication of the reports. This undoubtedly contributed to Thomson's failing health and his death at the early age of only 52. Murray was eventually able to secure the Treasury's financial backing, partly by shaming them when he threatened to finance the publication himself. |
The final result is that the excellent reports, residing in the libraries of dozens of major laboratories around the world, are constantly referred to by modern oceanographers. And rarely a day goes by when a visiting scientist from one or other of those laboratories is not sitting in a room in The Natural History Museum, carefully studying specimens from the superb collections on which the reports are based. The reports contain thousands of illustrations, including many photographs and a few of Wild's watercolours. But Wild was only moderately talented as an artist, and although he illustrated some of the animals collected in their fresh state, the vast majority of the originals of the illustrations in the reports were produced either by the individual scientists to whom the various animal groups were sent, or by artists and engravers engaged by them. Consequently, instead of being dominated by one or a small number of artists, the pictorial material from the Challenger Expedition is the work of literally dozens of artists, engravers and lithographers most of whom never even saw the ship let alone sailed on her. |
Despite the accolades which the Challenger Expedition has justifiably received from marine scientists in the subsequent century and a quarter, it did not encourage the British Government to continue support for oceanography in the immediate aftermath. So shocked was the Treasury at its unintended generosity, that it was to be several decades before it again became involved in a comparably expensive scientific undertaking. Fortunately, other nations did follow the Challenger's lead. In the last quarter of the 19th century, major oceanographic expeditions were despatched from the United States, Germany, Norway, Sweden, France, Italy and Monaco. The newly opened oceanographic trail blazed by the Challenger was well on its way to becoming the broad international co-operative highway that it is today. |
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