754 



E. HILL AND T. G. BONNET ON THE 



42. The Precarboniferous Rocks of Charnwood Forest. — Part I. 

 By the Rev. E. Hill, M.A., F.G.S., Fellow and Tutor, and the 

 Rev. T. G. Bonney, M.A., F.G.S., Fellow and late Tutor, of 

 St. John's College, Cambridge. (Read June 6, 1877.) 



Contents. 



Introduction and general description. 

 Sections described : — 



1. Forest Gate to Longcliff. 



2. Buck Hills and Whittle Hills. 



3. Hanging Rocks and Beacon Hill. 



4. Woodhouse Eaves and Broom- 



briggs. 



5. Swithland and Blore's Hill. 



6. Bradgate. 



7. Benscliff. 



8. Newtown-Linford District. 



9. Groby District. 



10. Markfleld to Chitterman Hill. 



11. District up to Bardon Hill. 



12. Green Hill ( Whitwick) to Char- 



ley Wood. 



13. High Towers to Ives Head. 



14. Monastery, Peldar Tor, and 



Ratchet Hill. 



15. High Sharpley and Great-Gun 



Hill. 



16. High Cadnian to Blackbrook. 

 17- The Whitwick breccia. 



18. Bardon Hill. 



19. Bawdon, Moorley Hill, and 



Brazil Wood. 

 Correlations of Beds. 

 The relations between the Igneous and 

 Stratified Rocks. 



Introduction and General Description. 



Charnwood Forest, as is well known, is a hilly district composed of 

 a number of rather parallel ridges with a general trend from N.W. 

 to S.E. These hills rise to a height of a few hundred feet above an 

 undulating plain of Mesozoic rocks, which on the eastern side is inter- 

 rupted by the wide valley of the Soar. They consist of rocks most 

 of which are more or less metamorphic ; but some are igneous ; iso- 

 lated bosses also crop up here and there from the surrounding Trias. 

 This deposit runs, as it were, in fjords into the recesses of the older 

 rocks, besides dividing the district by a kind of strait or sound. To 

 the S.W. and S. the Trias stretches far away ; but on the W. (not, 

 however, much modifying the configuration of the district) lies the 

 Leicestershire Coal-field. A boss of hornblendic granite, Mount- 

 sorrel, crops up at the western edge of the Soar Valley ; and three 

 or four masses of a somewhat similar rock occur at a greater distance 

 to the south. These most likely are all outliers of the highland region 

 of the forest, which is really the culminating point of an old moun- 

 tain-land. This was probably to some extent defined before the 

 Carboniferous epoch, and formed a scattered group of hilly islands in 

 the Triassic waters. 



The district has been investigated by Professor Sedgwick, Pro- 

 fessor Jukes, Professor Ansted, the Rev. W. H. Coleman, and several 

 others. An exhaustive list of the papers upon it will be found in 

 4 The Geology of Leicestershire,' by W T . J. Harrison, Esq., F.G.S. 



According to the map published by the Geological Survey, the 

 Forest consists chiefly of rocks of Cambrian age. These, for about 2j 



