THE GEOLOGY OF TYTHERINGTON AND GKOVESEXD. 5 



The silicious limestones are remarkable beds, very 

 dense and hard in the solid ; the upper bed, which is the 

 more silicious, weathering at surface to a friable red sand- 

 stone. A fragment of this treated with dilute hydrochloric 

 acid effervesces briskly, but on the cessation of the action 

 of the acid, still retains its form and consistency ; if then 

 treated with concentrated hydrochloric and boiled, the acid 

 is stained deeply yellow by ferric chloride, and there 

 remains a white sugary sandstone. Under the lens the 

 rock is seen to be almost entirely composed of grains of 

 detrital quartz, cemented by calcareous matter, and with 

 here and there dark-red scales of ferric oxide. After 

 treatment with acid, the lens shows that the rock is sugary 

 from the removal of the calcareous matter and iron scales. 

 The percentage of insoluble matter, after treatment with 

 acid, is 72'05. The stone is used for road-metalling, and 

 has a resistance to a crushing stress of 14,694 lbs. to the 

 square inch, as determined by Messrs. Kirkaldy.* 



In the midst of the " Eire-stone " there are seen, where 

 the beds outcrop at the surface, lenticular masses of 

 Lithostrotion irregulare^ and on the dip-slope of Limestone, 

 exposed by the removal of the overlying '' Fire-stone," fine 

 branching stocks of the same coral are abundant. In the 

 lower bed of " Fire-stone " Mr. Win wood obtained Spirifera 

 octoplicata and Athyris glohularis. It is, however, exceed- 

 ingly difficult to obtain satisfactory fossils from this quarry, 

 though Producti and Lithostrotion are abundant. About 

 15 feet above the " Fire-stone " occurs a bed, the surface 

 of which, where exposed, is crowded with Brachiopods and 

 Euonipliali (?) ; all, however, in bad condition for extrac- 

 tion or recognition. Both above and below the ^' Fire- 



* "Highway Management. Proceedings of a Conference held at 

 Gloucester, 1886." Appendix I., page 50. 



