350 Mr. Hutton's Notes on the New Red Sandstone of 



shall designate the upper bed as the Yellow Sand, from its pre- 

 vailing character, and the lower as the Red Sandstone ; but 

 without in the least wishing them to be considered in any other 

 light than as different members of the same formation. 



When the magnesian limestone first enters the county of 

 Durham from the south, its course is so little marked for se- 

 veral miles, from the lowness of the level at which it runs, that 

 the beds beneath it cannot easily be examined : — proceeding 

 northward, however, it begins to rise into those round-top- 

 ed hills which form the general character of its edge through- 

 out the county ; the red sandstone keeps its course near the foot 

 of these hills, and was first met with on the side of the road 

 leading from Legs Cross Toll Bar, towards Heighington; 

 about a hundred yards beyond, the well-known Cockfield Dyke 

 crosses the road ; the basalt, which has been woi-ked for a 

 road-stone, is seen cutting through the yellow sand. 



Park House Quarry, on the hill side, one mile west of 

 Heighington, is worked entirely in the red sandstone ; it has 

 been lately opened out ; the stone is of a close texture, and is 

 used for gate-posts, &c. ; the limestone is not seen in the 

 quarry, but it forms the capping of the hill above, and is ex- 

 tensively worked about three hundred yards to the east. 



At Brusselton, near the top of the hill, close by the turn of 

 the road, the yellow sand is visible on the road side. In the 

 great quarry beneath the tower, there is a very fine display 

 of the red sandstone in all its variety of colour and texture, 

 having beds or seams of a hard, light blue, siliceous shale, 

 running through it in the most irregular manner; the bed 

 must be here of considerable thickness, as the quarry has been 

 worked at least fifty feet deep. 



In Thickley Quarry, by the side of the Darlington railway, 

 the same kind of stone is extensively worked, as is found at 

 Park House Quarry and Brusselton. The upper bed is a 

 slaty limestone ; a light blueish white clay occurs here in irre- 

 gular seams. It was in a quarry a little to the east of this, 

 by the side of the railway, that the curious deposit of fossil 

 fish occurred, which is described by Professor Sedgwick in 

 his Memoir ; they were found in a slaty limestone bed, very 

 near the sandstone. 



At Eldon, the limestone forms the top of the hill, and pro- 

 ceeding northward towards Howlish Hall, although the red 

 sandstone does not appear at the surface, yet there is suffi- 

 cient evidence of its existence beneath, in the deep rich red 

 colour of the soil on the slope of the hills immediately under 

 the limestone. 



At Cowndon, a fault, running nearly north and south, 



throws 



