Correspondence — C. Reid — J. E. Marr — 8. 8. Buckman, 527 



COK/ie-IESIF'OIsrXDIEIsrGJB:. 



OFF ASTER PILULA. 



Sir, — Mr. Sherborn is right as to the unfortunate slip in the 

 recently published Memoir on the Geology of Southampton. Having 

 Dr. Barrois' book open before me when I wrote the paragraph, 

 I seem to have forgotten for the moment the more recent authorities. 

 Elsewhere I have correctly referred the highest Chalk in that 

 neighbourhood to the zone of Actinocamax quadratiis. 



Clement Eeid. 



October 8th, 1902. 



LAKES OF SNOWDONIA. 



Sib, — In my letter which appeared in the September number of 

 your Magazine (p. 430, line 16 from top of letter) is an erratum 

 which destroys the significance of the sentence. For ' sunny ' read 

 ' snowy.' J. E. Mark. 



Cambridge, October 9th, 1902. 



EIVER DEVELOPMENT. 



Sir, — Because I frankly admitted that statements in my paper in 

 Natural Science, vol. xiv, 1899, might be termed " mere speculation," 

 giving as the reason that the maps which we can obtain do not 

 supply sufficient information for the precise study required, 

 Mr. Strahan thinks he was justified in characterizing my work as 

 " transgressing the limits of legitimate speculation." Yet he had 

 just admitted not having seen the paper in Natural Science when he 

 made that remark. 



There is all the diiference between my admission and Mr. Strahan's 

 remark. Any theory is a speculation. I gave the grounds 

 on which the theory was based ; and I followed out the logical 

 conclusions. The basis of the theory is that the original rivers 

 flowed with the dip. As the general dip of the area in question is 

 from north-west to south-east, that involves an original river-system 

 such as was depicted in my map. Strong evidence in favour of the 

 theory is found in the peculiar course of the tributaries on the left 

 bank of the Severn, and in the breaches of the Cotteswold 

 escarpment. 



It is difficult to admit that in a country of simple structure such as 

 the Cotteswolds, a Chalk anticline and all that it involves could 

 be masked. 



As to the indefinite westerly rise of the Chalk, is it so very 

 great ? The rise of the Oolitic surface on which the Chalk could 

 have rested is about 800 feet in 25 miles. Having regard to the 

 thickness of the Chalk and the extent of its outcrop, can its rise be 

 much more than this? 



One word about the Moreton anticline. I described an anticline 

 there, formed and covered over again in Inferior Oolite time. We 



