438 Topley — Physical Geography of East Yorkshire. 



hii' 



traversing the whole length of the Vale of York, its waters are 

 carried iato the Humber. Many such examples 

 might he given in. other districts.^ 



The connection between the internal structure of 

 a district and its physical geography is well illus- 

 trated in the case of isolated hills separated from 

 the main mass of a formation. These have very 

 commonly a synclinal structure, the beds dipping 

 into the hills on inost sides. Every hill of this 

 kind may be considered as an escarpment returning 

 upon itself, constantly changing its direction as the 

 dip changes. The picturesque hills of North Cleve- 

 land are syncliuals. This is plainly seen when 

 looking south from Eedcar at Eston Nab and Up- 

 >: leatham Hill. The Middle Lias is here worked for 

 S Ii-onstone, and the waste heaps on the hill sides 

 "g shew the dip of the beds, Mr. Marley, in his papet 

 ^ already referred to, gives a section which shows the 

 m same aiTangement in a transverse direction, so that 

 "=^' the beds composing these hills dip on all sides into 

 the hill, and the sides are all somewhat steeply 

 scarped. 



It is evident that such hills retain their form 

 because of this synclinal dip, in the same manner 

 that an escarpment, with its beds dipping into the 

 "g hill, retains its steep slope. If the beds dipped in 

 ■§ the reverse direction the sharply scarped face could 

 a not long be retained, as in the process of weather- 

 'j^ ing masses would slip away and slide down with 

 Z the dip. 



3 This tendency of hills having an inward dip to 

 "§ resist atmospheric degradation and thus preserye 

 2. their form has been pointed out by Mr. Euskin in 

 "S his "Modern Painters,"^ and by Mr. J. P. Lesley 

 ■a in a little book on "Coal and its Topography."^ 

 ^ Many examples of synclinal hills and conversely 

 . of anticlinal valleys might be given. Thus Mr. 

 Z Hull, in describing the Physical Geography of the 

 Cotteswold HUls, says,* " the anticliaals have pro- 

 duced lines of weakness, originating valleys ; and 

 the synclinal lines of strength, originating head- 

 lands." Mr. G-eikie has noted similar facts in 

 Scotland. He says,® " Ben Lawes is in reality 

 formed of a trough of schists, while the valley 



' See Eamsay, OjJ. Cit. p. 80. 



2 Vol. lY. " Mountain Beauty." 1856. Chap, xiii., xiv. 



3 12mo. Philadelphia, 1856. Chap. iii. "Topography as 



* ftuart. Journ. Geol. Soc. Vol. XI. (1855) p. 483. 

 ^^ Sceaery and Geology of Scotland. (1865) p. 96. 



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