of the Yorkshire Coast. 2 1 3 



strata in our hills, and the frequent undulations of the strata aU 

 ready noticed, some remarkable interruptions occur which de- 

 mand observation. At the mouth of the Esk, a slip or down- 

 cast has taken place on the north side, the whole mass of the 

 strata on that side being 80 or 100 feet lower than the corre- 

 sponding strata on the south side ; and this interruption seems to 

 be continued throughout the whole vale of the Esk. A similar 

 break is seen about two miles to the south of Carleton alum- 

 Vorks, where the north part of a hill has sunk wholly down about 

 ten feet, exposing the section of a bed of sandstone, which, when 

 viewed from the north, appears exactly like a stone wall running 

 across the whole ridge from Bilsdale to Scugdalo. 



But the most singular interruption of the strata is that produced 

 by the whinstone dyke, or basaltic ridge, which traverses our 

 liills, like a vast vein. This is perhaps the most remarkable 

 ridge of the kind in Britain, being 40 feet thick and often more, 

 and being traced on the surface to the extent of 60 or 70 miles, 

 in a straight line. It runs from Cockfield Fell in the county of 

 Durham to the river Tees near Preston; and then, entering 

 Cleveland, it crosses our district in the line laid down on the 

 map, but has not been traced quite to the coast, the last discern- 

 ible portion being at Blea hill, near the up|)er end of Harewood 

 dale. The ridge rises perpendicular to tlie strata, and conse- 

 quently inclines towards the south, the dip of the strata beinij in 

 that direction: it proceeds nearly from\V.N.W. to E.S.E. and 

 seldom deviates from the straight line. In manv places it does 

 not reach the surface ; in some, the top of it is on a level with 

 the surface, or protrudes only a foot or two above it, as on the 

 moor between Maybecks and Silhoue*, and in the descent from 

 Silhoue towards the Mirk Esk; in other places it rises to a great 

 height above the surface, as at Parker's hone near Lealholm 

 Bridge, and especially in the long and lofcy ridges which it forms 

 in Cleveland. In these prominent parts of the whinstone dyke, 

 it occupies a much wider space than the breadth of the vein; for 

 there the higher portions of the ridge, having nothing to support 

 them, have fallen down on both sides, especially on the south 

 side to which it inclines: and hence such protul)erances assume 

 the form of oblong hills. The most remarkableMiill of this de- 

 scription is on the south and west of Rosebury Topping: it is 



* Here the moor road that runs contiguous to it is c-iUecUhe H.._;h- street, 

 probably from the resemlilance which the ridgebcarstoapaved'io.id; though 

 it is possible, that a lloaian vicinary way may have passed in tliis direction, 

 from the camp on Lease-ri{;j^ to tlie fort at Peak. 1 mi^^ht have noticed, in 

 speaking of the Roman roads, that some houses near Loftus are called Street- 

 houses, which favours the idea that a Roman road inigiit run that way from 

 Dunsley to the mo\ith of tl-.e Tees. 



O 3 named 



