

n 



** lb* 



► 



the 





J 



" C(, sterski fL 

 of beds, 



atl 'S and b. 



freestone, i 



'''-tones of 

 inly and ft 



i Eyeford 

 o slates. \i 



xpo 



aed to i 



11-case 



4f 



w 



estone, 







1 rin 



«*<*' 



lime 



stone' 



) feet 



inite* 



thi* 



»' o 



e 



beds 



ire ^ 



I ,ur is* 1 



LIMESTONES. 



71 



L T PPEH 



band of what might be called a " Terebratula conglomerate,' 



4 inches thick, made up entirely of these and a few other Gal ^by. 



shells cemented together. The shells are frequently hollow, Wall-case 43 



• 'l"arried f . and encrusted with calcareous spar." (See " Memoir on the 



Map 44," by Edward Hull, p. 39.) 

 7. — Oolitic limestone, Great Oolite, from the upper zone 



of the great oolite. — Near 



rfi 



Oxon. (See the above Memoir, p. 63.) 

 8. — Purbeck marble, compact shelly limestone, prin- 



cipally composed of Paludina carinift 



Peveril Point 



Dorset 



) 



ly for buildii; narvonshire. 



9. - Cambrian limestone, a polished cube of red compact 



siliceous limestone. — Porthfelen, near Aberdaron, Caer- 



rchitecture.'- 



• The Geoio; 



} & Map t Island, Caernarvonshire. 



10. — Cambrian limestone, polished cube of compact 

 limestone, or grey marble, used for making lime. — Bardsey 



This is an unfossiliferous metamorphic limestone, from 

 the gneissic rocks of the Cambrian strata. It is from one of 



frost into tli several small lenticular bands, all of which are usually very 



, a l)le of \0 siliceous and difficult to polish. — A. C. R. 



The ma* 



^founded* 



11. — Wenlock 



Silurian limestone, locally termed "Ledbury marble* 

 formed chiefly of small corals. — Malvern, Worcestershire. 

 Presented by the Rev. Francis Dyson. 



12. — Carboniferous limestone, compact and crystalline, 

 formed chiefly of fragments of Encrinites. Used as a flux 

 in iron smelting. " Trivil white limestone." — Sirhowy Iron 

 Works. Monmouthshire. 



13. 



Upper 



fragments of trap rock, and rendered sub-crystalline by the 

 neighbourhood of a mass of intrusive trap. Used in con- 

 siderable quantities for making lime.— Near Old Radnor, 

 Radnorshire. 



14. — Encrinital limestone, Carboniferous Limestone, 



chiefly composed of crinoidal remains Middleton Moor, 



Derbyshire. 



