Non- Identity of Suffolk Diluvium and Crag. 285 



Art. V. Letter from The Rev. W. B. Clarke, on the Non-Iden- 

 tity of Suffolk Diluvium and Crag. 



My Dear Sir, 



As nothing tends so materially to the increase 

 of error, as ascribing to others those opinions or expressions 

 which they do not employ, I am sure that you will allow me 

 to make a remark or two on the note which you have append- 

 ed to my letter "in reference to the alleged occurrence of the 

 bones of terrestrial Mammalia in the red and coralline crag 

 of Suffolk." (P. 224—225). 



I have alluded in that letter to Mr. Lyell's opinions respect- 

 ing the relative ages of the crag and diluvium ; and my words 

 are, — ' I have shewn that the diluvium and crag are not, as 

 Mr. Lyell has supposed, of the same age.' To this you have 

 added in a foot-note,- — ■ The above observation of Mr. Clarke's 

 appears to us calculated to convey a wrong impression of the 

 opinion Mr. Lyell has advanced upon this subject; for al- 

 though he may have referred certain beds to the tertiary epoch, 

 which more properly belong to the diluvial, yet we think there 

 is no ground whatever for assuming that Mr. Lyell has consi- 

 dered, in an extended sense, the diluvium of SufFolk and Nor- 

 folk to be of the same age as the crag.' — Ed. 



Giving you credit for that desire to be candid and fair which 

 I assume to myself, I must beg you to compare my assertion 

 respecting Mr. Lyell's views, as to the unity of age of these 

 formations with his own words, in which he conveys, 'in an 

 extended sense,' all and more than I have attributed to him. 

 After describing the composition of the crag beds, and what 

 I term diluvium, together with their transported and foreign 

 contents, he says, — ' It has been questioned whether all the 

 above-mentioned beds can be considered as belonging to the 

 same era. The subject may admit of doubt, but after exa- 

 mining, in 1829, the whole line of coast of Essex, Suffolk, 

 and Norfolk, I found it impossible to draw any line of sepa- 

 ration between the different groups. Each seemed in its turn 

 to pass into another, and those masses which approach in 

 character to alluvium, and contain the remains of terrestrial 

 quadrupeds, are occasionally intermixed with the strata of the 

 crag.' (Vol. 3, 8vo. ed. ch. xiii. pp. 171 & 172). 



You will now, I am assured, acquit me of misrepresenting 

 Mr. Lyell's opinions. It is true, however, that in the last e- 

 dition of his 'Principles &c.' he has adopted another view. — 

 He says, (ed. 5, 1837, vol. iv. p. 76), 'Superimposed upon the 

 fossiliferous crag in the cliffs of Norfolk and Suffolk, is a for- 

 mation of much greater thickness and of more uncertain age. 



