2o6 GEOLOGICAL NOTES. 



Street terrace or to an older one, the slight valleys worn in the 

 gravelly plain to the underlying London-clay tend much to 

 obscure its nature and real elevation, when viewed from a point 

 between Ley Street Station and the Cran Brook. 



Beyond the Cran Brook northward, there are, as already 

 mentioned, no cuttings for a distance of more than two miles. 

 The next begins in a field on the more southerly side of Manor 

 Road, between Grange Hill and Frog Hall, where the line 

 begins to turn westward. North of Grange Hill Farm there is a 

 tunnel about 270 yards long, westward of which is an open 

 cutting as far as Newbarns Lane, Avest of the road between 

 Chigwell and Woodford Bridge. Beyond the spot at which the 

 line crosses Newbarns Lane are the marshes of the Chigwell 

 Brook and the Roding which are traversed by means of an 

 embankment. And the slight cutting close to the junction with 

 the Loughton line is too shallow to afford anything of geological 

 interest. 



Between Manor Road and Newbarns Lane the cuttings and 

 tunnel are in London-clay. But here and there west of the 

 tunnel there are many pebbles on the surface of the clay, 

 especially near the spot at which the Hainault Road crosses the 

 line. The new railway here touches the northern boundary of a 

 patch of gravel which is shown on the map of the Geological 

 Survey (i. N.W. drift edition) as existing mainly south of the 

 line and between the Hainault and Chigwell Roads. It is 

 coloured as old river gravel, and is about a mile north-west of 

 the gravel of Fairlop Plain and fifty or sixty feet higher in level. 

 It would, therefore, appear to be of more ancient date than that 

 of Ley Street and Fairlop Plain, and of less antiquity than the 

 glacial gravel north of Chigwell. The railway cutting, however, 

 does not afford any good sections in this gravel ; that which 

 appears here and there towards its top having been apparently 

 washed down from the land south of the line. 



East of the new line, in a field south of Manor Road at its 

 junction with Vicarage Lane, appear, in old English letters, the 

 words " Cing well (site of)." This is, I suppose, the well alluded 

 to by Mr. Whitaker {Gcol. Loud., etc., vol. I., p. 504) when 

 speaking of the sandy beds in the London-clay which sometimes 

 give rise to small springs, frequently medicinal — " I have heard 

 that a spring on the south of Chigwell Row was nuich appre- 

 ciated in the neighbourhood." 



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