212 baker's north YORKSHIRE. 



Osmotherley are lower both than the arenaceous hills further 

 west, and the calcareous range on the south. They are much 

 undulated by the heathery glens in which run the branches of 

 Codbeck and the Rye, the summit of the watershed ridge being 

 here 1,048 feet above the sea-level. Above Silton a spur of the 

 arenaceous range stands out into the low country, and behind 

 it is Black Hambleton (1289 feet), which is at once the highest 

 point, and the termination in a western direction of the escarp- 

 ment towards the north of the calcareous range. Opposite 

 Kepwick and behind a round outlying mass of hill, called 

 Kepvvrick Nab, is a bleak, undulated hollow, shut in by moors 

 upon three sides, in which a branch of Codbeck takes its rise. 

 Above Kirkby Knowle and Boltby another spur of arenaceous 

 hill spreads out westward and south-westward from the main 

 range. Above Kirkby Knowle this moor is 880 feet in height, 

 and has a craggy crest, and a little tarn in a hollow, formed by 

 a landslip, upon its slope. In front of Boltby the moor is some- 

 what higher, and has a steep embankment, covered with fir 

 plantations ; and the escarpment, still capped with Lower 

 Oolite, but much lower than Boltby Moor in elevation, is con- 

 tinued still further in a south-western direction, as far as 

 Feliskirk and Mount Saint John, from which point it declines 

 gradually into the low country. The main body of this rounded 

 spur of hill is called Black Moor, from which on the north-west 

 Wool Moor or Knayton Moor is separated only by a narrow 

 glen. In the hollow between Black Moor and the main range 

 another branch of Codbeck takes its rise, the two branch glens 

 of which open out at the village of Boltby. The western of these is 

 the most interesting — a deep, boggy, heathery, and wooded hollow, 

 called Gurtof Gill, to which in times past the Thirsk naturalists 

 have often resorted for mosses, and Oak and Beech Fern. 



Above Kepwick and Black Moor the calcareous table-land 

 reaches a height of from 1,100 to 1,200 feet. From Boltby to 

 where opposite Hood Hill it turns abruptly due east the con- 

 tinuity of the hill-bank is unbroken. The distance in a direct 



