LIST OF ILLUSTRATIONS 
* IQ ' PAGE 
176. Section from the great Limestone escarpment on the west to the Millstone Grit hills 
east of Teesdale ......... 4 
177. Sections of the Carboniferous Limestone series of Northumberland showing the varia- 
tions in the position of the Whin Sill. By Messrs. Topley and Lebour . . 6 
178. View of two volcanic necks in the Carboniferous Limestone series, at Grange Mill, 
five miles west of Matlock Bath, from the north . . . . .14 
1/9. Plan of necks and bedded tuff at Grange Mill, five miles west of Matlock Bath . 15 
180. Section across the smaller volcanic neck and the stratified tuff in Carboniferous Lime- 
stone, Grange Mill ......... 15 
181. Section of vesicular and amygdaloidal diabase resting on Carboniferous Limestone, 
Peak Forest Limeworks, Great Rocks Quarry . . . . .19 
182. View of the superposition of Carboniferous Limestone upon toadstone, Raven’s Tor, 
Millersdale (length about 100 feet) ....... 19 
183. Section at limekiln, south of Viaduct, Millersdale Station . . . .20 
184. Limestones passing under stratified tuffs, Poy 11 Vaaish, Isle of Man . . .24 
185. Section of tuff, showing intercalations of black impure chert, west of Closenyehollagli 
Point, near Castletown, Isle of Man . . . . . . .25 
186. Section of intercalated dark limestone, shale and chert in the tuff south of Poyll 
Vaaish Bay, Isle of Man . . . . . . 26 
187. Section of part of a volcanic neck on shore to the south-east of Poyll Vaaish Bay, Isle 
of Man ........... 29 
188. Section of successive discharges and disturbances within a volcanic vent. Scarlet 
Point, Isle of Man ......... 29 
189. Section of dyke and sill in the tuffs west of Scarlet Point, Isle of Man . • 30 
190. Section on south side of vesicular sill west of Scarlet Point . . . .31 
191. Bands of vesicles in the same sill . • • • • 31 
192. Croghan Hill, King’s County, from S.S.W. . . . • • .38 
193. Section in quarry on roadside east of Limerick, close to viaduct of the Limerick and 
Erris Railway .......... 44 
194. Section of the volcanic escarpment, east of Shelian’s Cross-roads, south of Limerick . 45 
195. "View of Derk Hill, a volcanic neck on the south side of the Limerick basin . ■ 4/ 
196. Section across the Limerick volcanic basin . - ■ • • .48 
197. Section of a bed of volcanic breccia in the Carboniferous Slate ; White Bull Head, 
County Cork . . . . . . . • .50 
198. Volcanic breccia invading and enclosing Carboniferous slate, White Bull Head . 50 
