34 EARLY LETTERS [Chap. I 



Letter 12 a mound has been thrown across a considerable valley, but 

 even against this mound there is no appearance of even a 

 small pool of water having collected after the heaviest rains 

 The water all percolates straight downwards. Ascertain 

 average depth of wells, inclination of strata, and springs. 

 Does the water from this country crop out in springs in 

 Holmsdale or in the valley of the Thames? Examine the 

 fine springs in Holmsdale. 



The valleys on this platform sloping northward, but ex- 

 ceedingly even, generally run north and south ; their sides 

 near the summits generally become suddenly more abrupt, 

 and are fringed with narrow strips, or, as they are here called, 

 " shaws " of wood, sometimes merely by hedgerows run 

 wild. The sudden steepness may generally be perceived, as 

 just before ascending to Cudham Wood, and at Green Hill, 

 where one of the lanes crosses these valleys. These valleys 

 are in all probability ancient sea-bays, and I have sometimes 

 speculated whether this sudden steepening of the sides does 

 not mark the edges of vertical cliffs formed when these 

 valleys were filled with sea-water, as would naturally happen 

 in strata such as the chalk. 



In most countries the roads and footpaths ascend along 

 the bottoms of valleys, but here this is scarcely ever the case. 

 All the villages and most of the ancient houses are on the 

 platforms or narrow strips of flat land between the parallel 

 valleys. Is this owing to the summits having existed from 

 the most ancient times as open downs and the valleys having 

 been filled up with brushwood ? I have no evidence of this, 

 but it is certain that most of the farmhouses on the flat land 

 are very ancient. There is one peculiarity which would help 

 to determine the footpaths to run along the summits instead 

 of the bottom of the valleys, in that these latter in the middle 

 are generally covered, even far more thickly than the general 

 surface, with broken flints. This bed of flints, which gradually 

 thins away on each side, can be seen from a long distance in 

 a newly ploughed or fallow field as a whitish band. Every 

 stone which ever rolls after heavy rain or from the kick of an 

 animal, ever so little, all tend to the bottom of the valleys ; 

 but whether this is sufficient to account for their number I 

 have sometimes doubted, and have been inclined to apply to 

 the case Lyell's theory of solution by rain-water, etc., etc. 



