204 
DEPOSITS OF DOUBTFUL AGE. 
large pit showing a thickness of 30 feet, with marked current¬ 
bedding. Above these pebbly beds, close under the Boulder 
Clay, and nearer to the station, light-coloured sand, bedded with 
layers of pebbly gravel, was seen at a spot now covered by the 
embankment of the South wold line.”* * * § 
It is in the district south of the Blyth that the Pebbly Beds 
take up most area (compared with other deposits), forming the 
level hilJ-tops, except for sundry mostly small cappings of Boulder 
Clay. But they are cut through everywhere by the valleys, 
which reach to the underlying sand, except in the case of that of 
tlie Blyth itself, in which the Pebbly Beds reach down to the 
marshes in three places, on the southern side. 
There seems to be a good deal of difference of opinion as to 
the correlation of the strata seen in Dimwich cliffs ; for the 
gravels referred by Mr. Whitaker to the Pebbly Series, are 
by Prof Prestwich and S. V. Wood considered to be glacial. 
These pebbly gravels are almo.st confined to two portions of the 
cliff—the southern end, and close to Dunwich. The gravels are 
continuous inland for two and a half miles, as far as to Westleton, 
near which place they pass under the plateau of Boulder Clay, 
only occasionally to reappear in the deeper valleys. The 
Westleton Sands and Shingle ” in the typical locality are thus 
described by Pi of. Prestwich. f “They attain a thickness of 
from 30 to 40 feet, and consist of a series of stratified beds of 
well-rounded flint-pebbles imbedded in white sand. They look 
more like the pebble-beds of Blackheath than any other beds in 
the eastern counties. Mixed with the flint-pebbles are a few 
small pebbles of old rocks, with a considerable number of white 
quartz-pebbles, the presence of which constitutes a distinctive 
feature of these beds throughout their range.” 
These Westleton Beds have been traced as far south as the 
Minsmere Level; beyond that point they are not identified by 
the Geological Survey, though Mr. WhitakerJ has suggested the 
possibility of the gravel being represented, in a distant part 
of the London Basin, by a gravel of like character as well also 
as of doubtful age. Prof. Prestwich goes further, and corre¬ 
lates with the Westleton Beds various outlying patches of gravel 
scattered over the counties of Essex, Middlesex, Hertfordshire, 
Surrey, and other portions of the Thames valley.§ 
Whilst these pages were passing through the press. Prof. 
Prestwich published a new series of three papers on the 
“Westleton Beds.”|| In these papers he reiterates his already 
* Geology of Halesworth and Harleston. {Mem. Geol. Survey')^ p. 15. 
t Quart. Journ. Geol. Soc., vol. xxvii., p. 461. (1871.) 
X Guide to the Geology of London. {Mem. Geol. Survey.') Ed. 3, p. 57 (1880,) 
and Ed. 5, pp. 58-60. 
§ On the Extension into Essex, Middlesex, and other Inland Counties, of the 
Mundesley and Westleton Beds .... Rep. Bril. Assoc, for 1881, p. 620, and 
Geol. Mag., dec. II., vol. viii., p. 466. (1881.) See also H. B. Woodward, Notes 
on the Bure Valley Beds and the Westleton Beds. Geol. Mag., dec. II., vol. ix., 
p. 452. (1883.) 
II Quart. Journ. Geol. Soc., vol. xlvi., pp. 84-181. (1890.) 
