562 ISLE OF MAN. GEOLOGY. LIMESTONE. 



cations of violence, are impressed on the unstratified rock. 

 In the stratified one, the usual appearance of straight 

 joints, filled with ordinary or magnesian carbonate of lime, 

 occurs, but in no great abundance. The unstratified is, 

 on the contrary, penetrated by innumerable fissures cross- 

 ing each other in irregular directions, and filled with the 

 same materials. Here also, at the entrance of the Santon 

 river, is to be seen the breccia which was formerly men- 

 tioned. This is a part of one of the irregular beds, and 

 it consists of fragments of the crystalline rock, cemented 

 by the same substances which fill the rifts of the limestone 

 in other places ; as if in this particular spot the rock had 

 been broken into fragments, instead of yielding in a body 

 to the impression of the disturbing force. 



After :thus minutely detailing the changes apparent at 

 this junction, it is proper to say that, in many other 

 instances, it is impossible to trace any passage from the 

 crystalline rock to the ordinary one, nor from the unstra- 

 tified to the stratified disposition ; but that the change is 

 sudden and perfectly defined ; while, at the same time, the 

 proximity of the schist cannot be detected. 



There is yet another distinct set of appearances, con- 

 nected with the change from the stratified to the unstra- 

 tified limestone. There are two examples of this, each 

 of which is sufficiently distinguished from the other to 

 require a separate detail. 



Near Scarlet point, the successive beds of stratified 

 limestone are to be traced in a flat position; following 

 each other in a very even and regular manner for a con- 

 siderable space. On a sudden they undergo an undula- 

 tion in repeated curves, and are then intersected by a num- 

 ber of trap veins.* These veins are repeated at intervals 

 for some distance along this shore in proceeding westward. 

 They all lie in a position more or less erect, and their 

 general tendency is towards the south-west ; but as they 



* Plate XXVII. fig. 3. 



