Vol. 50.] RAILWAY FROM ROMFORD TO UPMINSTER. 447 



and Danbury which overlooks tbe valley between tbose places and 

 Laindon, Hadleigh, and Rayleigh. North and nortb-west of Rom- 

 ford, around Havering-atte-Bower and Chigwell Row, tbere is little, 

 if any Boulder Clay at a level lower than 200 feet above the sea, 

 except at Maylands, on the western flank of the valley of the Ingre- 

 bourne. In a broad and general way it may be stated that the 

 height at which the Boulder Clay exists diminishes as we travel 

 from the west eastward. Thus, towards the southern edge of the 

 high ground between Warley and Danbury, it may be seen here and 

 there below the 200-foot contour line at heights from about 170 feet 

 upwards ; and no Boulder Clay whatever is visible on the top of 

 the ridge of Tiptree Heath, though it appears in the low ground 

 north-west of the ridge. 



Turning to the river- valleys, we may note that though the 

 Boulder Clay keeps, as I have said, to ground of 200 feet and up- 

 wards at Havering-atte-Bower and Chigwell Bow, yet it may be 

 seen 40 or 50 feet lower in the valley of the Boding, to the north- 

 west, and in that of the Ingrebourne at Maylands. Eastward, 

 around Chelmsford, it appears at various levels between 100 and 

 200 feet, also about Hatfield Peverel and Witham. And in the 

 river-valleys between Chelmsford and Maldon it descends here and 

 there even below the 100-foot contour-line. 



Thus in the existence of Boulder Clay in the valleys of the Roding 

 and of the Ingrebourne near Romford, and in those of the Black- 

 water and its tributary streams around Chelmsford and Maldon, we 

 have evidence of their excavation, to some extent, before the depo- 

 sition of the Boulder Clay. And as the height at which Boulder 

 Clay appears in these valleys decreases eastward, we have reason to 

 believe that the drainage of this district took, as it now does, an 

 easterly course at the time of the deposition of the Boulder Clay. 



Assuming then, as seems most probable, that in the silted-up 

 channel at Romford we have that of an ancient river, it is obvious, 

 in the first place, that it must have belonged to an earlier system 

 than that of the present Thames Valley, as it is manifestly older 

 than the oldest Thames Valley gravel ; secondly, that the Roding 

 and Ingrebourne must have been among its tributaries, as is shown 

 by the lower level of the Boulder Clay south of Romford than in the 

 valleys of those streams ; and, thirdly, that this Romford river flowed 

 in an easterly direction. We have now to consider its probable 

 course eastward. 



I think there can be little doubt that, granting the above hypo- 

 thesis, the course taken by the ancient stream disclosed in the Rom- 

 ford cutting was through the broad tract of low ground between the 

 heights of "Warley, Billericay, and Danbury on the north, and those 

 of Laindon, Hadleigh, Rayleigh, and Althorne on the south. 

 Crossing the present valley of the Crouch, it entered that of the 

 Blackwater about midway between Woodham Ferris (or Ferrers) 

 and Althorne (where the water-parting between the basins of the 

 two streams is now only a little more than 50 feet above the sea), 

 and joined the Blackwater somewhere east of Maldon. 



2h2 



