146 HoivartJi : The Ice-home Boulders of Yorkshire. 



deposits along the northern face of the Cleveland Hills and on 

 the eastern side of the Vale of York, seems to indicate that the 

 Northumberland and Durham local glaciers were, like the Tees 

 glacier, prevented from discharging seawards. They were thus 

 compelled to turn southwards across the Tees, and were forced 

 up the northern slope of the Cleveland Hills by the Scandi- 

 navian ice on the one hand, and the Tees glacier (which simi- 

 larly had to turn southwards down the Vale of York), on the 

 other. 



It seems curious that among the very numerous examples 

 of Cheviot rocks, there should be no record of Cheviot granite, 

 beyond one doubtful specimen found at Upsal, near Thirsk. 

 It is just possible, however, that Cheviot granite may, com- 

 paritively speaking, have only been recently reached in the 

 process of denudation. The great boss of true granite seems 

 almost complete, and there are still portions left of the rocks 

 which covered it. Possibly the explanation is that Cheviot 

 granite is a bad traveller, and easily disintegrated. Similarly 

 we might expect to find such rocks as Tynemouth dyke. Much, 

 however, remains to be done in the way of microscopical exami- 

 nation of many recorded ' basalts ' and ' dolerites,' and these 

 dyke rocks may very likely be present though unidentified. 



THE EASTERN GROUP. 



Boulders of Scandinavian origin are found in very great 

 numbers on the shore on the Yorkshire coast, in the claj^s and 

 gravels forming in places the coastline ; on the top of the coast 

 cliffs at the Peak and Speeton, and at many places inland, 

 both in drift material and on the surface. They range from 

 Saltburn, all along the coast to Redcliff and Ferriby, on the 

 Humber, and in vertical distribution from the sea-shore to 810 

 feet above sea level. In a gravel pit at Burstwick, in Holder- 

 ness, they were found 16 feet below the surface. 



These rocks are recorded on the coast at Saltburn, Staithes, 

 Whitby, Kettleness, Robin Hood's Bay, Gristhorpe, Filey, 

 Dimlington, and Easington ; inland at Ayton, Seamer, Hutton- 

 Buscel (in the Vale of Pickering), and in Yedmandale, at 

 Garton-on-the- Wolds, and up the Humber Valley ; also at 

 Kirk Moorgate, near Whitby, at 550 feet, O.D. ; at the Peak at 

 600 ; Danby, at 625 ; Stump Howe, 650 ; on Eastington High 

 Moor, at 700 ; and at West Rigg (in the Lockwood Hills), at 810. 

 These rocks are also recorded in Lincolnshire and Norfolk. 



{To he contimied). 



Naturalist, 



