'34 PROF. T. G. BONNEY ON THE NARBOROUGH DISTRICT. [Feb. 1 89 5, 



explain on any theory. The absence either of well-worn rock- 

 surfaces or of any material disturbance of the surface of the Keuper 

 appears not to accord well with the hypothesis of an ice-sheet and a 

 moraine profonde. At any rate, the journey of such a sheet up the 

 valleys, first of the Trent, then of the Soar, must have been a long 

 one, and the route somewhat circuitous and difficult. 



Discussion. 



The Rev. Edwin Hill mentioned the present extensive use of 

 these rocks for road-material. This paper confirmed the supposed 

 connexion with those of Groby and Garendon, but showed that their 

 specific gravity varied in a way entirely different from the variations 

 in their coarseness of structure. These observations agreed with 

 those formerly made as to the absence of glacial striae where they 

 certainly ought to be found, if an ice-sheet had moved in any 

 direction whatever over Central England. 



Prof. Hull, while recognizing the interest attached to the Author's 

 investigations on the igneous rocks of the district, wished to remind 

 the Society that a very important question bearing on the geology 

 of this part of England still remained for decision : namely, the 

 age of the Charnwood Eorest rocks. No reliable fossils had as yet 

 been obtained from these beds ; and any observer who should succeed 

 in discovering one or more organisms of a decisive character would 

 add an interesting chapter to the physical geology of Central 

 England. 



Mr. Eutlet also spoke. 



The Author said that, in regard to the specific gravity, he 

 thought that chemical composition was a more important factor than 

 crystalline condition. He had never been able to see that there was 

 any reason for calling the Charnwood rocks Cambrian, other than 

 that they were not very like any known Cambrian. He had never 

 been fortunate enough to find any fossils. 



