342 



Correspondence — Mr. E, Wilson. 



I mentioned that the section as shown in Fig. 1 lies at the top of 

 a hill between two faults., as shown in plan (See Fig. 2). 

 Not that the district between the two faults is a continuous ridge ; 

 there are other ridges with dry, irregular valleys between. I 

 think there can be no doubt that the space between the two faults 

 has been raised higher than the outlying district so short a time ago 

 (geologically), that the country within the faults has since that time 

 preserved a relative, if not an absolute similarity of contour, with 

 that outside the faults. 



Alluvium. 



f 6. Red Marl with 

 beds of White 

 Sandstone. 



f 5. Soft Sandstone 

 and Marl (Water- 

 stones). 



f2. Pebble-beds or 

 Conglomerate. 



A and B, white lines, 

 Faults. 



[Near the letter B, be- 

 tween a white and a 

 black star, is the 

 line of section seen 

 in Fig. 1]. 



Nottingham. 



N. &L.E,.:= Nottingham 

 and Lincoln Railway. 



N. & G. R. = Notts and 

 Grantham Railway. 



J inch to 1 mile. 



Fig. 2.— Sketch-map of a portion of the District near Nottingham, showing the position of 

 the Faults in the Red Marls of the Keuper and Bunter. 



Therefore, upon such elevation, perhaps that last one which 

 gave the country its present contour, subject to subsequent 

 denudation, we should have the data for the elevation of a curved 

 svTface (not due to the earth's rotundity) producing the fault- 

 ings shown in Fig. 1. These minor faultings, as far as a mere 

 section across their direction can show, seem to run parallel to the 

 larger, including faults. I have spoken of valleys between the 

 ridges. Would the elevating force act also on the inverted arches 

 those valleys formed ? Clearly so ; but the results would differ, for 

 faults would be produced which would hade to the ttpthrow. The 

 elevation, then, of a basin-shaped curved area I believe is the cause 

 of the production of this class of faults, on a small if not on a large 

 scale. It is also evident that contortions would be produced by the 

 elevation of an inverted arched area, as they are produced by the de- 

 pression of an arched area. 



I understood from Mr. Wilson's paper that the faults will not take 



