110 Horace B. Woodward — On Landscape Marble. 



Turrilepas 



Ske)iidium,Ti.s^ 



Jlolopea 



Orthoceras vagans, Salt. 



Corniilites 



Myclodactylus ? 



Ghjptocrinus 



Ogijgia 



Fhacops apiculatiis. Salt. ... 



' eucentra, Ang 



Thyllopora Hisingeri, M'Coy 



Orthis actonice, Sow 



• hiforata, Schlot. 



■^— — calligranuna, Dalm. ... 



elcgantula, Dalm. 



protcnsa, Sow 



• tcstudinaria, Dalm. ... 



' vespertilio, Sow. 



Strophomena siluriana, Dav. 



Theca triatigularis, Portl. ... 

 Xellerophon 



Ashgill; Troutbeck; Swindale. 



Billy's Beck. 



Troutbeck. 



Troutbeck. 



IIIb. Ashgill Shales. 



Skelgill ; Backside Beck. 



Backside Beck. 



Skelgill. 



Troutbeck. 



Eebecca Hill ; Troutbeck. 



Ashgill ; Troutbeck. 



Backside Beck, 



Skelgill. 



Skelgill; Ashgill; Swindale; Backside Beck. 



Skelgill. 



Skelgill ; Swindale. 



Skelgill; Ashgill; Swindale; Backside Beck. 



Skelgill ; Applethwaite. 



Skelgill. 



Troutbeck; Skelgill; Ashgill; Rebecca Hill; 



Swindale ; Fairy Gill ; Backside Beck. 

 Skelgill. 

 Ashgill. 



II. — Remakks on the Formation of Landscape Marble. 

 By Horace B. "Woodward, F.G. S. 



THE Landscape Marble or Gotham Stone is one of the best known 

 of our English ornamental rocks. Polished slabs of it may 

 be seen in most museums ; and there are fashioned out of it paper- 

 weights, ring-stands, and other useful objects, which raay be 

 purchased on Clifton Down and elsewhere. 



This stone came into notice when it was quarried, together with 

 other beds, near Gotham House, on the northern side of Bristol ; 

 and it was described in considerable detail in 1754 by Edward Owen, 

 who then gave it the name of "Gotham Stone." ' 



It is a hard, close-grained ai'gillaceous limestone, which breaks 

 with a fracture almost as conchoidal as that of flint ; and it is 

 characterized by dark arborescent markings which pervade the 

 stone. These markings rise from a more or less stratified base, 

 and terminate upwards in the wavy banded portion of the limestone, 

 which varies from one to about nine inches iu thickness. ITaus 

 when slabs, cut at right angles to the planes of bedding, are 

 polished, there may often be discerned (with the aid of the imagina- 

 tion) a landscape with a prominent row of trees and bushes, with 

 clouds above, and perhaps the semblance of water in the foreground.^ 



The lower surface of the limestone is even, though sometimes in 

 small masses of the rock it is gently curved ; the upper surface is 

 corrugated, and the irregularities appear to correspond in many 

 instances with the original planes of deposition, for thin layers that 



^ Observations on the Earths, Eocks, Stones, and Minerals, for some miles about 

 Bristol, etc., 8vo. London. 



" An illustration of the Landscape Marble was published in the Proc. Geol. 

 Assoc, vol. i. p. 209. 



