218 FAMOUS GEOLOGISTS/Sedgwick structure to some extent, and although the rocks seemed to have few fossils, the Cambrian System was introduced, largely on the basis of Sedgwick’s work Murchison, starting in the Welsh border region in gentler country with fossiliferous rocks, had an easier time and revealed what appeared to be a new system with its characteristic fossils, dubbed the Silurian However, the line of boundary between the two systems was not established at the outset of the investigations in 1834, with the result that a bitter feud subsequently broke out between Sedgwick and Murchison, with the former trying to extend ‘his’ system upwards, the latter endeavouring to expand ‘his’ downwards, eventually to the very lowest fossiliferous rocks (The issues were very complex; it was not until after the protagonists’ deaths that the issues were resolved, by Charles Lapworth, who, in 1879, proposed the Ordovician System to occupy the disputed territory between the Cambrian and Silurian (see Palaeozoic: Ordovician) Sedgwick had complained, with reason, that materials he had sent to the Geological Society were changed so as to accord with Murchison’s views, without Sedgwick’s knowledge or consent The situation grew so bad between the two that after 1853, the Geological Society declined to accept further papers by the protagonists of Siluria or Cambria Sedgwick felt grievously ill treated and snubbed by the Society The battle became transferred to the forum of the British Association, but after 1854, Sedgwick withdrew from that body also, so far as the Cambrian and Silurian were concerned, and continued the battle from Cambridge and in the pages of the Philosophical Magazine Some of the stratigraphic formations and their classifications are shown in Figure It should be noted that the rocks that Murchison allowed to be Cambrian in 1859 were the unfossiliferous Longmynd rocks, later classified as Precambrian (Murchison also allowed Sedgwick the unfossiliferous Torridonian Sandstone in Scotland, also now regarded as Precambrian.) Initially, Murchison won the battle, partly because he had better fossil evidence, and placed full reliance on it Also, he had strong influence in the Geological Society and became Director of the Geological Survey in 1855, and his classifications were used by the survey officers Sedgwick had fewer allies, mostly at Cambridge For the rocks he was dealing with, he had to rely on structural understanding and lithologically based mapping to a greater extent than did Murchison (Graptolites were not regularly used for stratigraphic correlation in the mid-nineteenth century.) However, Sedgwick succeeded in showing, on palaeontological grounds, that the claimed unity of Murchison’s Silurian System was flawed In 1852, Sedgwick and his assistant Frederick McCoy found that one of Murchison’s Silurian formations, the Caradoc, had rocks containing two distinct faunas, as shown by the palaeontological determinations of McCoy and John Salter There had been erroneous correlations; the same term, ‘Caradoc Sandstone’, had been applied to different series of rocks; and there should be an unconformity within the Caradoc, as Murchison then understood it Sedgwick proposed the division of Murchison’s Caradoc into the Caradoc Sandstone, containing fossils such as Trinucleus, and an upper May Hill Sandstone, containing Pentamerus species This eventually turned the tide against his Silurian being regarded as a coherent system The Survey sought to retrieve the situation by adopting the terminology ‘May Hill Sandstone Llandovery’ rocks, regarding them as a kind of passage or ‘Intermediate Series’ between the Upper and Lower Silurian There were repercussions, too, for the interpretation of Murchison’s Llandeilo This battle was fought with extreme vehemence Both geologists attached their names and reputations to ‘their’ system The battle seemed to exemplify the height of the colonial era, with Sedgwick and Murchison trying to extend their empires Murchison was popularly called the ‘King of Siluria’ Both men tried to rewrite history in their historical accounts of the events In Sedgwick’s case, this may have been partly due to failing memory Earlier, there had been a bitter controversy in Devonshire, where, while still friends, Sedgwick and Murchison began to unravel the structure and stratigraphy of the area, in the process becoming involved in controversy with Henry De La Beche, the first Director of the Geological Survey From this acrimonious debate emerged the concept of the Devonian System The so-called Old Red Sandstone was the unit well known in eastern Scotland as lying unconformably over Silurian strata It was mapped by William Smith as ‘Red and Dunstone’ He placed it below the Coal Measures and below a limestone that cropped out in Derbyshire and elsewhere In Devonshire, there occurred rocks with plant remains that appeared to De la Beche to belong to the old Transition/Greywacke series (Cambrian or Silurian rocks) In Murchison’s opinion, however, the plant-bearing rocks could not be so old: they must be from the Coal Measures But he had not then been to Devon to see the rocks for himself Murchison then combined forces with Sedgwick to combat De la Beche’s interpretation It was an issue of more than academic significance because it bore on the question of the possible extent of coal-bearing rocks The plant-bearing rocks overlay contorted rocks of ancient appearance, but these contained corals