Cambridgeshire was also a place of industry, based on farming needs; its oddest industry was coprolite-digging, the extraction of phosphatised clay nodules for fertiliser. Coprolites occurred in a belt from Soham to Barrington and were exhausted in a rush between 1850 and 1890. It was an industry unique in England. Nodules were excavated in trenches, yielding 300 tons an acre.
Why did coprolite production start at this particular time? There are two important factors to consider; partly the increase of geological knowledge and above all the accidental discovery of the mineral by someone who was certainly no geologist. A miller named John Ball, of Burwell, owned land just outside the town, on the Fenland edge. How exactly he came across the coprolites will never be known. He may have discovered that his turnips were growing with extraordinary liveliness and dug the earth up to see what was underneath. But what is certain is that in 1851 he discovered the hard rounded fossils which, at that spot, would only have been a few feet below ground, in the Greensand. He dug out a quantity and according to Lucas (1931), a fenland doctor who had heard the story by word of mouth, washed the clay off them and ground them to a powder in his windmill. He then treated the powder with an acid to make a fertiliser. This process was probably similar to that used for processing bones and dried blood for manure and this explains his seemingly broad scientific knowledge.
Apart from Ball's activities, there is very little evidence of anyone mining coprolite until the end of the 1850's. There are two main reasons for this. Firstly, in such a widespread and traditional industry as agriculture, practices always take a long time to catch a hold; in the same way, crop rotation spread extremely slowly. Ball probably found sales difficult enough, even though he was the only producer in the field. Added to the difficulties of opening a market, there were transportation problems; the railway network was still limited and river tolls still high. The second important factor was the public's lack of accurate geological knowledge that was so important with thin seams of mineral. Even university geologists had little experience in the complexities of the Gault and Chalk Marl, let alone the average landowner or tenant farmer. It seems that, up to 1860, most coprolite was only discovered accidentally.
The first recorded discovery of a coprolite bed after 1851 was at Cambridge in 1858 on Coldham's Common, probably where a pit was being dug for brickmaking. Practically all pits to the south were opened in the years 1858-70 and until 1872 there were no pits to the north of Cambridge except at Swaffham and Burwell. This is not to say that production was always higher in the former group; in fact, the converse is true. There are a number of possible reasons for this distinction. The first is a severely practical one; there was no bridge between Cambridge and Ely across the River Cam until one was built at Clayhithe in 1872, so that contact could be made with the railway at Waterbeach. Until then only sites adjacent to navigations were worked. There may also have been a great prejudice against disturbing the peat soil, the best in the world, until it was realised that bringing up the undersoil was beneficial. The balance between profits from normal agricultural activity and the costs of transporting the bulky coprolite must surely have been an important factor in production here.
By 1880 almost every landowner along the relevant geological outcrop, roughly on a line drawn from Soham to Royston, must have been involved directly or indirectly with coprolite extraction. As early as 1863 the effect of expansion was being felt on transport; mostly of coprolites being taken to the factory. There was an early conflict between rail and road interests becuase the turnpike was not getting its share of the profits from the already large amount of coprolite traffic originating from workings and factories in the Abington Pigotts and Clopton area. Initially, at the small workings, the coprolite was loaded into a cart after being washed and was taken by road to the manufacturer. By 1873 things had changed. The map of workings at Clayhithe shows a large system of 'tramways,' perhaps as long as 3 miles. An estate map of the same area in 1875 also includes tramways but in almost all cases these have been removed completely or shifted to another field. Clearly, as a mine was worked, the tramway was manhandled to a new position and work could then have begun anew. The tramway was thus of a very temporary nature needing flanged wheels for bullhead rail and which were difficult and expensive to construct: the 'tramways' would have possibly been 'plateways' made of simple 'L' shaped girders along which horses drew wooden-wheeled trucks. At a minimum yield of 200 tons of nodules per acre 13-15,000 tons of coprolite had to be shifted. But no bridge existed across the Cam to reach the railway from the eastern fenland until 1872 and the old fenland lodes were at first in too bad a state to take large industrial lighters. This lack of facilities and the realization of the profits that farmers were making in the south of the county prompted the rebuilding of equipment in the north. The Bridge across the Cam at Clayhithe was built in 1872 a wharf also existed. From here the mineral was taken in barges to Cambridge, Ely or Kings Lynn for subsequent distribution by sea.
Further north in the Fens, a long way from the railway, at Upware, Wicken and Reach, river transport was always the only way of distributing coprolite, road transport being far too expensive and unreliable. Here, rather than companies searching for transport facilities for their particular working, they would pick an area of greensand through which a navigation ran. In three cases this was already available; at Bottisham, Reach and Burwell Lodes. At other places the extreme slowness of river transport made it inevitable that the railways should eventually become the biggest carrier. Tolls were no more expensive by train, either. Added to this, the Great Eastern Railway had lost most of through coal traffic to the East Coast Great Northern main line, and was very eager to make up for it.
As prices show phosphate was the cheapest form of fertiliser apart from animal manure, but the proportion of farmers that used it is not known. The phosphate would arrive, not bagged, but loose in a cart. Modes of applying the fertiliser varied. The powder might be mixed loose with animal manure and distributed by hand from a cart on the fields in the traditional way. Used by itself, however, the phosphate marked a definite improvement in agricultural practice. One part of phosphate was mixed with six parts of water and placed in a fertiliser drill. The drill differed from a seed-sowing apparatus. The was used for most of the 'root' vegetables such as turnips, mangolds, swedes and sugar beet. The fall in the production of coprolite was by no means as sudden or confident as the rush had been in the early 1870's.
The factors governing the decline are more far-reaching geographically and less obvious than the expansion. One complication is that a primary lull started in 1878. An increase then followed, reaching its climax in 1885, from which year the permanent decline can be dated. The reasons for the first lull was due to extensive imports from abroad, especially from America. The Americans had discovered phosphate deposits in the states of New York and New Jersey; by 1880 the American market was saturated and they possibilities of the British market were now open to them. This and the decline of the seams in Cambridgeshire led to a decline in the industry. By 1900 there were virtually no mines left.
"The Cambridgeshire Coprolite Mining Rush" by Richard Grove, published by Oleander Press, ISBN0 902675 61 3.
Return to Main Index page page
Last Updated on: 13 January 2000
For comments about this webpage, please email Martin Edwards.
©1999. EnglandGenWeb and WorldGenWeb Project.