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HUGH PRUDDEN (1929- October 1992 when he led a field trip for the Bath Geological Society to and I 2015) GEOLOGIST AND remember well his enthusiastic and distinctive style of speaking and teaching. It TEACHER, AND THE was not Hugh’s style to stand in front of an “BLACK FILE” exposure or geomorphological feature, tell us what we were looking at and how it had happened or give an explanation. His style Charles Hiscock was very much the teachers’ way – we were told to look at the feature or subject, work out what we could see and then come up with explanations or descriptions. On that trip we walked from Minehead harbour west along the coast to the flat grassy apron underlain by cobbles and pebbles at the base of North Hill known as Greenaleigh. I remember that, after giving us a clue or two, he asked us to work out why this grassy patch, bordered at the edge of the sea by a bank of cobbles, had formed and what mechanism was responsible for its formation. Because we had to work it out, I took in and retained the information to this day.

Earlier in this article I referred to the first coincidence associated with the Black File. In early February 2015, not a month after Hugh Prudden’s funeral, having been Elsewhere in this edition of the Bath fascinated by the mystery and contents of the Geological Society Journal, there is an article black file, I was re-examining the contents entitled ‘An Unsolved Mystery’ in which I and reading many of the articles. Then the recount the story of how a black spring- second coincidence occurred. On pages 373 backed file, containing 264 sheets of paper of and 374, I found an article, typewritten with 3 typewritten articles transcribed from papers photos, entitled ‘Boulder Clay of Bedford’ by in scientific and geological journals and from H C Prudden, from the ‘Bedford Magazine’. newspapers and magazines, came into my (Boulder Clay is the old name for glacial till). possession for safe keeping as Archivist for There was no date or volume number. At the Society. I also tell how, coincidentally, a first I could not believe that it was the same few days after looking through the contents author but ‘Prudden’ is not a common and discovering a paper on the ‘Cannon Shot surname, and with the initials ‘H C’, I had to Flints’ of Norfolk, we went away for a week to assume that our Hugh Prudden and the near Cromer, north Norfolk. This was the first author of this typewritten transcript was one coincidence associated with the Black File. and the same.

On 8th January 2015, at the age of 86, Hugh The internet is unbelievably helpful to us in st Prudden died, having lived at Montacute near the 21 century so I naturally went to it to , , for much of his life. Hugh start my investigations with the intention of was a much respected geologist who finding the original article in the Bedford remained active in his chosen subject, Magazine. The name of the magazine was particularly in Somerset, very much to the not helpful so I looked up H C Prudden. end of his life. At his funeral service there Unsurprisingly, there was a wealth of entries were over 200 people with one of the tributes under his name, almost exclusively given by Professor Hugh Torrens, being a concerned with the of Somerset, its fine demonstration of how much he was districts and environs. Disappointingly, there respected. I first met Hugh Prudden in was no reference to the article ‘Boulder Clay of Bedford’ although his name did appear in

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other links with boulder clay. My next changes, became stratified rocks. The sea-bed attempt was to email the Bedford Tourist rose and fell, and accumulated the thick deposit of Information Centre with the information and that underlies the whole northern half why I was interested in tracking down the of the county. Then it was raised as a great land article. Their prompt reply was that they had mass. Gradual denudation followed, and it is not heard of the publication but had passed believed that the was deposited in my enquiry to the Archive office at the turbulent straits, existing intermittently, making Borough Council. The reply from the what is now mid-Bedfordshire a region of shifting Bedfordshire and Luton Archives Service sand-banks and powerful currents. In the office was more promising in that they hold extending sea was deposited the Clay that copies of the Bedfordshire Magazine and forms a narrow strip across the county; during that they had found the article that I was further subsidence of the seabed the thick of interested in. However, it was entitled ‘‘The south Bedfordshire was deposited, derived in part Ice sheet that invaded Bedfordshire’ written from the skeletons of countless millions of minute and illustrated by H.C.Prudden’. Published in marine animals and in part from chemical Spring 1953, vol III, pages 345-348, it was precipitation. Again the whole area was raised as about boulder clay and was written by Hugh a land-mass, and subjected not only to denudation when he would have been about 24, but also to gentle tilting and folding, the distant probably around the time he graduated from effects of the tremendous epoch of mountain- Cambridge University. The title was a building that formed the Alps. surprise because, as a result of my investigations on the other articles in the When we come to more recent geological Black File, the titles of the transcribed times, say the last million years, we begin to see articles always matched those of the original the present physical landscape emerging. Several paper in the geological journal, magazine or times the climate deteriorated, and great sheets of paper. However, the Archive service passed ice accumulated and flowed out from the me on to the Bedfordshire Historical Record mountains of northern Europe; the sea-level fell, Society which holds the copyright of the now and cut down to lower levels; the severe defunct Bedfordshire Magazine and they climate intensified erosion, and valley bottoms were very happy to give permission, for were choked with debris in the form of gravel. which I thank them, to reproduce the article for the Bath Geological Society Journal. The The ice that invaded Bedfordshire was an original article is longer than the transcribed extension of the ice-caps that were expanding from version in the Black File and is reproduced the mountains of Britain and Scandinavia under here as scanned from the Bedfordshire the influence of heavier snow falls and lower Magazine. temperatures. Streams of ice from the British hills converged with the Scandinavian ice in what is The Ice-sheet that invaded now the North Sea, turned southwards along the East Coast and probably approached this county Bedfordshire from the north and east. Written and Illustrated by H. C. Prudden, B.A. The most extensive of the deposits brought by the ice-sheet was the Boulder Clay. Mostly a For the most part the land of fine-grained and soft material, it contains an Bedfordshire is made up of formations of clay, astonishing variety of ingredients. In it can be limestone, sand and chalk rock. Of these deposits distinguished igneous and metamorphic rocks the limestone rocks are the oldest. They date back from the Cheviots, southern Scotland and to times, about 135 million years ago, Scandinavia; and quartzites from the when Bedfordshire was part of the southernmost Midlands; Jurassic limestones, and clays; of two great islands which lay in a sea between and chalk, flint and limestone from Lincolnshire. ancient 'North Atlantis' on the west and an extension of the present Scandinavia covering The mixture was deposited partly from the most of the North Sea on the east. underside of the moving ice-sheet and partly from Over these millions of years vast changes melting stagnant ice. It differs from the gravel took place in the relative positions of land and of deposits in that it has been little, if at all, sorted by sea. Rivers, wasting the land, carried into the sea running water and therefore contains boulders of sediments which, after chemical and physical rock, large and small, in its clay matrix. Farmers

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valley have used the larger stones for walls, or for cobbled paths. The route of the advancing ice streams must have been affected by the topography. It is difficult to say what the pre-glacial topography was like, because of glacial and post- glacial changes, but the Chalk and Greensand areas of south and mid- Bedfordshire stood, as now above the adjacent clay vales, with the Ivel and perhaps part of the middle Ouse, draining towards the Wash. There is evidence that powerful ice movements occurred where the Ivel valley narrows in crossing the belt of more resistant Lower Greensand. A well sunk south -east of Biggleswade went through a transported mass of Jurassic clay 67 Figure 1: A typical section of Boulder Clay, the most extensive of ft. thick, which rested on 10 ft. of fine the deposits brought by the ice-sheet, showing large boulders in the glacial mud. clay matrix At Northill nearby, another well revealed 104 ft. of Boulder Clay and hikers in north and mid Bedfordshire will resting on Oxford Clay at about sea level. It was have met the Boulder Clay in newly ploughed once thought that this deep infilled valley was cut fields on hilltops, where it forms a stony, at a time when the sea level was low, but since no tenacious clay with lumps of chalk. Church- outlet to the sea has been demonstrated, it is more builders outside the limestone belt of the Ouse probably a great basin scoured out by a constricted stream of ice or by melt-water below the ice. There is evidence of similar action near Hitchin and Stony Stratford.

Like a huge blanket the Boulder Clay lies over the higher ground in the north of the county and is widespread about the centre. In places between the Ouse and the Nene it is over 100 ft. thick and there are thick drifts to the south-east of Woburn. Curious exceptions are the hills three or four hundred feet above Figure 2: Left : Gravels at Sundon, which were probably laid down by streams of melt-water draining off the nearby ice-sheet. Right : The upper part of Wilden Church porch incorporates Boulder Clay stones from neighbouring fields.

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are chipping flints into tools and hunting mammoth, although the advancing ice has driven most of them south towards more genial climes. If I read the records correctly (and there may be other versions), we shall see vast streams of ice squeezing up the lvel valley and moving over north Bedfordshire, the main body coming in from the north and east. To the south another stream of ice moves along the Gault Vale from Figure 3: General view of Sundon, where water-laid gravels and ice-deposited Cambridgeshire. As Boulder Clay rest on the white Chalk, a much older formation. it meets the higher Chalk and Greensand hills it is sea-level west of Ampthill, and little trace of diverted and flows around them. Further away Boulder Clay can be found on parts of the to the south and west, streams of melt-water plateau-like surface east of Sandy. Is this because rush towards the Thames basin, spreading later weathering processes have denuded some sands and coarse gravels along the valleys. hilltops? Or did parts of south and mid Bedfordshire stand above the ice and so escape The glaciation here described occurred glaciation? It seems likely that there was some in comparatively recent geological times, and melt-water issuing from the ice, since water- although no further ice-sheets appear to have spread gravels can be seen at Sundon chalk-pits encroached on Bedfordshire, its physical interbedded with Boulder Clay. landscape has been changed considerably during subsequent cold periods. At such times All in all, the ice probably deposited more conditions must have resembled those of material in Bedfordshire than it removed, for the present-day Spitzbergen, where perennially county was near the southern limits of the ice- frozen subsoils, heavy summer floods, and sheet. This is evident from the frequent scanty vegetation, contribute to a much more occurrence of a kind of fringe-drift of ‘foreign’ rapid wastage of the land than we experience rocks lying on the local rock formations. The here today. This wastage has removed for ever effect of the drift on the topography was probably much of the evidence with which we interpret to smooth and broaden it, choking up some geological history; yet there remain many former valleys in the process. unsolved problems and attractive lines of research concerning the formation of the Let us climb the pleasant hills at Sandy, Bedfordshire landscape awaiting those who and in imagination blot out town, railway, and care to peer back into the remote past. market gardens, and look out across the tundra that was Bedfordshire as it was during at least one stage of the Great Ice Age, a good 500,000 years ago. The nearest groups of Stone Age men I am very grateful to Mark, Hugh Prudden’s

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son, for allowing me to take extracts from the impassable at times. He led field trips, as th tribute that he gave at his father’s funeral. well as the one referred to above, on 13 April 1997 to ‘The Rocks and Buildings of Hugh Prudden was born in 1929 at Bedford Hestercombe House near ’, where he and educated at the Grammar School. During enthused about the Hestercombe his time of National Service, Hugh discovered lamprophyre which had only recently been th the and Somerset. However, it cleared of vegetation. On 28 April 2001 we was in his spare time in Bedford that he went were taken over Ham Hill near his home at th to evening classes where he met Professor Montacute, Somerset, and on 20 July 2002 Norman Pounds who encouraged him to on ‘The Geology and Wildlife of Mid nd study at Cambridge, and who remained a Somerset’. Then, on 22 May 2004 he led us lifelong mentor. Hugh studied Latin to a around showing us, or, as was sufficient level, an impressive feat, to enable Hugh’s way, getting us to examine and him to enter Cambridge. On leaving comment on the building stones of the Abbey, Cambridge, he navigated his way west with followed by another trip to Minehead and th teaching posts in Geography and Geology at Greenaleigh on 15 May 2005. The last field Tonbridge Wells, Cheltenham, and trip he led for us was called ‘The Yeovil Trail’ th finally at Yeovil. During his life, he was author on 16 July 2006. of two books on geology and published over 50 articles of geological interest. I have used Not only did Hugh lecture to the Society and Hugh Prudden’s book ‘Geology and lead field trips, he also provided three articles Landscape of Taunton Deane’ (2001) in which for the Bath Geological Society Journal and he describes the geology and landscape to be collaborated with Gilbert Green on a fourth. experienced on the many walks listed. I have As would be expected from an enthusiast for used the book on many occasions and, as a his adopted county, they were all concerned Somerset man myself, find it most interesting with Somerset – and useful about the area of my childhood Volume 25 p.33 2006 ‘Ilchester- home. He also published ‘Somerset Geology Barrington pipeline’. – A Miscellany’ in which there is a wealth of Volume 28 p.39 2009 ‘Somerset’s information on localities in Somerset, fantastic coastline seen from space’. including a comprehensive bibliography. One Volume 30 p.17 2011 ‘Book review – section entitled ‘Somerset Good Rock Guide’ Butterflies in Somerset and ’. lists many articles and publications which he Volume 27 p.34 2008 ‘The new BGS had authored over the years and is an Mendip Guides’ with Gilbert Green. invaluable guide to the information on the geology of Somerset. I am sure there will be other tributes to Hugh Prudden, but I humbly suggest that they read It is available to everyone via the Bath the tribute to Hugh Prudden, written by Geological Society website http:// another geologist who has adopted Somerset, www.bathgeolsoc.org.uk albeit much later in life than Hugh, Eric Robinson. It can be found in Volume 14, No Hugh Prudden was a good friend of the Bath 1, March 2015, page 12, of the Magazine of Geological Society. In addition to the first the Geologists’ Association where he adds field trip he led, referred to above, he lectured some more strands to the life of Hugh to the Society on 9th July 1992 ‘Rocks and Prudden. At the time of writing (April 2015) Landscape – The Yeovil Sands from volumes of the Magazine of the Geologists’ to the Coast’, and on Association are available on the internet up to 9th March 1995 ‘Soil erosion in south volume 13, no 3, 2014. Somerset’. I remember this lecture and the concern he expressed about the loss of good As recognition of Hugh Prudden’s contribution land due to the sandy nature of the soil and to geology, in 2007 he was awarded the R. H. methods of soil husbandry to prevent the Worth Prize by the Geological Society of wash-off. My parents had lived at South London, recognizing his work in bringing local Petherton for many years and I recall seeing geology to the notice of the public. He was the fields where the sandy soil had washed also awarded the Halstead Medal by the into the lanes and roads, making them Geologists’ Association in 1994.

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Deane – A geological exploration of In the tribute given by Hugh’s son at the south west Somerset’. Published funeral, he speaks of a thread running by Taunton Deane Borough Council, through his father’s life of someone always ISBN – 0-954052-0-2 141 pages. seeking to learn and apply his learning to This book was reviewed in the improve things for the benefit of all. Magazine of the Geologists’ Association, vol. Concluding his tribute, he said that his father 1, no. 1, March 2002 and the reviewer’s was a generous person, that he had achieved comment was ‘this modest book...... is a many things that are valued today, and that compendium of topographical and geological this value will live on, which was the hope of delight, full of arresting observations. It ranks Hugh Prudden, geologist, teacher and so as a best buy.’ much more. We in the Bath Geological Society have known that generosity and value 2001 – ‘Comments on further glacial tills on that he put on learning for all and are much , south-west : the better for it. implications for small ice-cap and valley glaciation’. In Harrison S et al, Proceedings of the Geologists’ Bibliography - not a complete list! Association, vol. 112, No 3, p.285-287 1953 - ‘The Ice Sheet that invaded 2003 – ‘Somerset Building Stones’. Bedfordshire’. Proceedings of the Somerset The Bedfordshire Magazine, vol Archaeological and Natural History 3, p.345-348 Society, vol. 146, p. 27-36 2004 – ‘Somerset – A Good Rock Guide’. There must be many more between Available as a download from the 1953 and 1983 which have not come to light! internet. 2005 – ‘Strike-slip faulting in Somerset and 1983 -‘ Tear faulting in south east Somerset adjacent areas’. (abstract)’. Geoscience in south west Proceedings of the Ussher Society vol England, vol. 11, p. 158-161 5, p.492. 2005 – ‘Rocks and landscape in and around 1985 – ‘Tourist Geology’. Yeovil’. Geology Today, vol. 1, no.6, Published by p.165/166. District Council 1987 – ‘Notes on the distribution of sarsen 2006 – ‘Somerset and Dorset Field Meeting stones in south Somerset and west (of the Geologists’ Association) Dorset’. Saturday 1st/Sunday 2nd October Proceedings of the Ussher Society 2005 with Robert Chandler. vol 6, p.557. Magazine of the Geologists’ 1989 – ‘The Glasgow Garden Festival’. Association vol. 5, no 1 Geology Today vol. 5, no.1, p.14/15. 2007 – ‘Letter to the Editor – Somerset 1992 – ‘New observations on the Ham Hill Geology Group’. Stone (Lower Jurassic)’. Magazine of the Geologists’ Proceedings of the Ussher Society, Association, vol. 6, no 4 vol. 8, p.492 (In Hart M.B et al). 2007 – ‘Ham Hill Geology – geology in 1995 – ‘Ham Hill – the rocks and quarries’. pictures’ South Somerset District Council. Available as a download from South 1996 – ‘Ham Hill in 1893’. Somerset Council website. Bulletin of the Somerset Industrial 2010 – ‘Field trips – a personal view – Hugh Archaeological Society, vol 72, p. 6- Prudden – Somerset Geology Group’ 11 Magazine of the Geologists’ 2000 – ‘The building stones and geology of Association vol. 9, no 2 Fine Court and Broomfield’. Leaflet available from the Somerset Wildlife Trust. 2001 - ‘Geology and Landscape of Taunton

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