328 GEOLOGY OF THE BKISTOL COAL-FIELD. 



continuation of the upper limestone series. It contains many- 

 univalves, whicli have, by many, been thought doubtful as Clifton 

 specimens. It is a dark semi-crystalline limestone passing into one 

 having a lighter colour. The fossils are very distinct from those 

 found in previous beds. 



Murchiso7iia angulata ^(Phill.) ; Platyschisma tiara (McCoy.), 

 Jamesoni (McCoy.) ; Naticopsis variata (Phill,), spirata (McCoy.) ; 

 Loxonema rugifera {^\n\]..) 'y Bellerophon apertus (Sow.)', Conula/ria 

 quadrisulcata (Mill.) ; SedgwicUa centralis (McCoy.). 



38. — Orthoceras led Q,onidims^Q2it\xQVQdi encrinites, and imperfect 

 specimens of a large orthoceras. 



39. — [2260]. — The Great Faulty very properly so named, and is 

 well worthy of a visit from every one studying the Clifton rocks. 

 This spot bears most evident testimony to the great convulsive 

 power that nature sometimes puts into action. Through the 

 distance of 1090 feet, the ground is distorted and broken up in the 

 utmost confusion, and the rocks twisted and overturned. The 

 strata has been displaced to the extent of 800 feet vertically. One 

 side upheaved, the other depressed and at the same time lateral 

 pressure completed the destruction. Beds of coal mixed with 

 millstone grit are side by side with mountain limestone, while the 

 500 feet of upper shales have been, as it were, buried out of sight, 

 and the Avon gorge riven asunder. All these are open to the eye 

 of the observer of the present day. So great was the disturbance 

 of the country, that one half was turned one-fourth of the whole 

 compass; the beds below the Great Fault dip to the S.S.E. 30°, 

 while those above the Great Fault dip to the N.E. 70°. At the 

 entrance to the tunnel, near the Clifton Station, coal beds may be 

 seen, which have been buried 300 feet in the ground, while the 

 same beds have, since that time, been entirely removed by 

 denudation from the surface of the higher ground in the immediate 

 neighbourhood. Complete evidence of lateral pressure may be seen 

 by the curling of the marls and shales as they were forced against 

 the massive beds of the St. Vincent's Eocks, which are only a 

 repetition of the mountain limestone before described. 



