PLIOCEl^rE PEEIOD TS ENGLAIfD. 501 



the west of it ; but immediately to the east of this confluence three 

 great accumulations of gravel, containing (in the westernmost of 

 them at least) a considerable intermixture of the cannon-shot flints, 

 occur at Mousehold, Poringland, and Strumpshaw, apparently resting 

 at the two latter places on the Chalky Clay. The Mousehold and 

 Strumpshaw accumulations are on the plateau of the north side of 

 the Yare valley, the former extending to within a mile of the 

 northern end of fig. IX. ; and the Poringland one is on the southern 

 plateau, two miles from the southern end of fig. IX. 



Under the conditions of westerly inclination, already described as 

 existing throughout the Chalky Clay, the part of the Wensum-Yare 

 valley which lies east of this confluence had a dififerent fall from 

 that which it has now ; for though the bottom of it has been found 

 at Yarmouth to be 170 feet below the marsh*, this at the time under 

 consideration, when all the county had a more westerly inclination, 

 stood proportionately higher eastwards ; and the valley being filled 

 with ice up to, and probably somewhat above, the level at which 

 fig. XYIII, occurs, there would have resulted an expanse neaj: this 

 confluence which, if filled with water above this ice, would have 

 been of considerable and lacustrine extent. North of this confluence, 

 however, the Wensum valley (especially where it crosses from 

 Sheet 68 to Sheet 66) would have much the same fall as at present. 



It seems to me that the torrents of water which issued from the 

 edge of the ice that thus rested high within the broken line and over- 

 looked the Wensum valley, pouring into that valley above the ice 

 which occupied it, by their torrential character washed out much of 

 the Chalky Clay here, and rolled the great flints in it into the 

 cannon-shot form described. Eastwards and southwards from the 

 place of the ice in mass here, this gravel gradually loses the cannon- 

 shot character, becoming finer and the great spherical flints fewer. 

 The three large beds of this gravel — Mousehold, Poringland, and 

 Strumpshaw — appear to have accumulated in the expanse just de- 

 scribed while the Yare valley still remained filled with ice. East- 

 ward of this the gravel along the Yare valley edges becomes finer, 

 and is seen covering the Chalky Clay thinly on the cliff-top on either 

 side of Lowestoft, where this clay overlies the gravel c ; and thickly 

 overlying it where this clay, cutting-out that gravel, lies in the 

 valley of the Waveney at Somerleyton brickfield and the railway- 

 cuttings at Mutford. The -finest material was carried further and 

 spreads widely over South-western Norfolk and North-west Suffolk, 

 while numerous patches of this gravel in its finer condition occur 

 along the edges of the Waveney valley. These latter Mr. Prestwich 

 identifies with the thin wrapper of gravelly sand which envelops the 

 denuded edges, and covers the whole surface of the palaeolithic brick- 

 earth of Hoxne ; and in that identification I agree. Erom Hoxne 

 westwards the same bed, increasing in thickness, and often becoming 

 a thick deposit of only sand, stretches northwards into inosculation 

 with the cannon-shot form of the deposit in the north-west of 

 * Prestwich in Quart. Journ. Geol. Soc. vol. xvi. p. 449. 



