206 Mr. Hutton on the Stratiform Basalt. 



ferous formation, I would object the great extent of the bed, its edge 

 having been traced regularly cropping out with the other strata for 

 above 100 miles, whilst it is found many miles within the formation in 

 fact, wherever the water-courses or the operations of the Miner pierce 

 deep enough ; it is affected by the veins cutting the formation equally 

 with the other beds, and bears Lead ore so as to be worked into and 

 through in many situations. In the upper part of Raven Beck, a 

 stream which joins the Eden, near Kirkoswald, the Whin appears three 

 times, although, as before described, there is but one bed here, it being 

 a constant character of this part of the escarpment to present broken 

 masses, which have slid down from their proper position ; in each of the 

 situations, it is in two layers, having a slaty micaceous Sandstone in it 

 from 18 inches to 2 feet thick. It is not easy to conceive how a mass 

 of matter, 10 fathoms in thickness, which had forced itself up from a 

 great depth, and insinuated itself into the solid strata, could have been 

 cut through by a Sandstone bed of 2 feet thick to so great a depth as 

 is here exhibited, and more particularly so as in Croglin Water, where 

 the Whin is again seen, on the other side of the hill (more than 2 miles 

 distant in a direct line), a Sandstone bed of the same nature is found in 

 it. But the most convincing argument of all is the almost total absence 

 of mechanical action, and what is to be seen being so entirely exhibited, 

 as far as I have been able to observe, at the under surface of the bed, 

 where it has frequently caught up and entangled masses of the inferior 

 strata. Professor Sedgwick has given some beautiful examples of this 

 in his description of the bed in High Teesdale, and I have given some 

 others ; but all, as before stated, exhibited in connection with the infe- 

 rior beds, whilst had the Basalt been forced in after the deposition of 

 the beds above it, such action was as likely to have taken place upon 

 these beds as upon those below. 



There is one character which the Whin Sill exhibits more or less 

 throughout its whole course, and that is an extraordinary irregularity 

 suddenly swelling out from 2 to 30, or even 40 fathoms in thickness. 

 Where this occurs its edge assumes a remarkably undulating form, and 

 the appearance of a set of round-topped hills. Upon Tepper Moor, 



