235 



QUARTZITE BOULDERS IN THE SCUNTHORPE 

 DISTRICT. 



ARCHIBALD C. DALTON. 



It has been previously shown* that we possess only a re- 

 arranged glacial deposit in this district, and that quartzite 

 pebbles were most abundant throughout the district. The 

 prevailing character of the area is the large quantity of ' Blown 

 Sand/ which is, in some places, over twelve feet in thickness. 



Many of the quartzites command special attention, on 

 account of their size, their shape and appearance. 



While those previously recorded were just small pebbles 

 and were found more often in clay, the specimens now under 

 consideration are large, and found chiefly in the blown sand, 

 they thus differ both in size and circumstances from those 

 recorded by Mr, J. W. Statherf above the line of glaciation on 

 the Chalk Wolds. 



The rock, as judged from the boulders, varies in nature 

 from a coarse grained one of a white colour to a fine grained 

 variety more or less deeply coloured, as if by the presence of 

 iron. 



In the Scunthorpe Museum there are some remarkably 

 fine specimens of the quartzite boulders, one of which is of 

 exceptional size, and weighs i cwt. 2 qrs. 8 lbs. 



The following are the measurements of the circumference 

 of a few typical boulders, including the one just referred to. 



' A ' . . 52 inches . . 42^ inches 



'B' .. 13I „ .. I3i „ 



'C' L . 13I „ .. 141 „ 



'D' .. 81 „ .. 71 „ 



From the above it will be seen that the boulders resemble 

 each other in shape. In appearance they are all polished by 

 the action of wind-borne sand, while the boulder ' A,' which 

 is flattened at one end, has the side, which faced the general 

 direction of the wind, pitted by the sand being hurled against 

 it, the other sides being just polished. 



The origin of these boulders gives rise to much speculation ; 

 they certainly appear to be distinct from the smaller pebbles 

 in my previous list, which were queried Trias by Dr. Dwerry- 

 house. 



Perhaps after more evidence is at hand, we may be able 

 to state something of the origin of these boulders ; at present, 

 opinion is in favour of their pre-glacial age. 



* A. C. Dalton, ' Glacial Evidences near Scunthorpe,' Nat. 1910, p. 377. 



t J. W. Stather, 'Quartzite Pebbles on the Yorkshire Wolds,' Nat. 

 1904, p. 9. 



191 2 Aug. I. 



