160 Sir Roderick I. Murchison on the 



" Cambrian." With this arrangement we both felt certain, that no 

 anomaly could be introduced into the lower palaeozoic classification, 

 as the relations and fossil contents of mineral masses which were 

 contiguous must be eventually cleared up, without fear of error, or 

 the introduction of theoretical views. 



The word " Cambrian" (as far as I know) was first used in print 

 by myself in the year 1836, in describing the structure of Pembroke- 

 shire. But whilst I then spoke generally of such Cambrian rocks, 

 and afterwards at greater length in my large volume, their analysis 

 and examination formed no part of my scope ; that task having been 

 specially undertaken by Professor Sedgwick, at a time when I really 

 believed, that from their great thickness, apparent inferiority and 

 different lithological structure, they would be found to contain a suite 

 of organic remains distinct from those I had called " Lower Silu- 

 rian." Improving in the following years the description of the Silu- 

 rian region, and having completed as well as I could by my own la- 

 bours (aided by a few kind friends resident in the country), the col- 

 lection of its typical fossils, I published in 1839 the " Silurian Sys- 

 tem," as founded on my own researches. This work was accom- 

 panied by a map, which, as far as the parts coloured Silurian are con- 

 cerned, has, I believe, been found little fault with ; the distinctions 

 of the Upper and Lower Silurian rocks, with their subordinate for- 

 mations (all perfectly conformable, be it observed, to each other) 

 being accurately laid down in reference to other overlying deposits. 

 But notwithstanding the labour bestowed upon it, this map was ne- 

 cessarily very defective in the boundary-line between the typified 

 Lower Silurian, and the wntypified Cambrian rocks. In the northern 

 part of the map that line was, indeed, for the most part inserted, at 

 my request, by Professor Sedgwick himself ;* and in Central and 

 South Wales it indicated, according to my view, little more than that 

 to the west of it, the so-called Cambrian rocks were then neither 

 zoologically nor physically explored — a task which, as repeatedly an- 

 nounced to the Geological Society, and expressly declared in my 

 work, wa^ left exclusively to Professor Sedgwick. But although it 

 was, so to speak, a point of honour with me not to trench upon the 

 privileges of the eminent geologist who had engaged to describe the 

 Cambrian region, I can truly say, that I repeatedly urged him to 

 determine the organic remains of those slaty rocks ; for I then 

 thought, I repeat, that they would be found to be in that manner 

 essentially distinguished from my Silurian types. Years, however, 

 rolled on, and this desirable end was not accomplished ; and no 

 peculiar fossils having to this day been published, the Cambrian 

 system consequently remained without organic characters of its own. 

 It was, in fact, a great physical mass without the vitality of a 

 system. 



''' -See de£criptlou of the map, >Sil. Syst., p. xxix. 



