: .r 



r. . 



Ante veins. Cornwall (De la Beci) 167 



64. Section of hmrbaddad igneou rock* LmJuhgowshw* 



w of the Island of Sufla and Kingal Cave, showing 



Benlary strata lying upon it . 170 



67 FTow-uructurr in n t'ppw Siluriwi rhyol. Ooftw Hd. 



DtaflB. natural sue 171 



in lava drawn out in the direction of the flow of 



and ftoatafe 



lo the rock . . . 



60. Cracks in an Old Rod Sandstone Uvm which have been 

 Mad In with sandstone from above, Coast of Kincardine- 

 shire 

 fa Crumpling and thrust-planes m fneiu. Sooth coast of 



1 80 



Salt. Donegal i8a 



7>. SchistoM Conflonerate. Three miles S.W. of Westport. 

 Mayo. Some of the blocks of quamite are two feet long, 

 and the matrix is a true schist . 185 



73. Beds of conglomerate and schist. Shore. Cataool. Isle of 



Arraa. The pebbles in the conglomerate have been 

 moved round and placed with their longer axes in the 

 plane of foliation (indicated by the arrow) which is ob- 

 ttque to the bedding of the schist 186 



74. Dyke changed into hornblende-schist. new Dunlanaghy. 



County Donegal The foliation of the schist runs 

 obliquely across the dyke, and traverses also the sur 

 rounding quart/ : 187 



iiatkM of mica.schist and grit hands coincident with bed- 

 ding ; rocks subsequently folded .... 188 



76. Map of part of the mining district of Gwennap. Cornwall 



.. Becbes Gtobfi'* 1 Oturvrr. p. 566) . 190 



77. Section of a mineral vein . 191 



78. Cliff cut into buttresses and riiceani by means of the verti- 



cal joints of the rocks . 195 



