492 S. V. WOOD, JTJN-., OS THE NEWER 



around wliicli this sand and gravel accumulated, as appears also from 

 figs. YI., YII., and IX. A comparison of this with Map 1 in 

 the field will show that this delineation is thus founded on actual 

 evidence from the broken line as far as the edge of the clay. Be- 

 yond this edge the delineation is based on the continuation of 

 the rise of the sea-bottom represented by this line of junction, 

 according to the increment of submergence traced in Stage II., 

 which, very fairly agrees with that of the line of this junction 

 as far as it extends, and with that of the line of the gravel over the 

 clay (e) which I shall trace in Stage Y. Within the broken line, over 

 the part where the junction has been for the most part destroyed, 

 this delineation is continued only in outline, and on the basis of the 

 decrease in the submergence eastwards towards Norfolk. The result 

 shows, in my view, a very close approximation to the geographical 

 conditions when the ice had reached the broken line. So far as the 

 land may have risen during the advance of the ice beyond it, and 

 before the shrinkage into the East- Anglian valleys took place, the 

 representation would not be exactly synchronous in all its parts ; but 

 this part of the rise was, I think, too small to make any appreciable 

 difference in the representation. The small islands or islets in 

 Sheets 48, 49, 50, 66, and 67 represent protrusions through the 

 gravel c of the beds of Stage II. such as those in fig. I., and they are 

 probably far more numerous and extensive than shown in the map — 

 those shown being only such as, occurring beyond or at the edge of the 

 Chalky Clay, or exposed by breaks in the pall of that clay, can be thus 

 detected. Most probably the tablelands out of which the river- 

 valleys of these Sheets have been excavated are to a great degree 

 formed of similar islands covered up by the Chalky Clay, such as that 

 on the south bank of the Waveney, from the summit of which 

 fig. XY. is taken, and where the moraine which overwhelmed 

 it has been forced or wedged into the surface of hS. Where the 

 moraine did not so entirely cover them we see this to have been 

 the case with the Wensum valley, which in the centre of Sheet 66 

 is thus formed, the long peninsula to the large island numbered 1 

 in Map 2 constituting the northern, and a small but long island the 

 southern side of that valley near Norwich. 



The representation thus given in Map No. 2 may be regarded as 

 that of the case when two thirds or rather more of the total rise, 

 which in Stage Y. is traced as having taken place during the forma- 

 tion of the Chalky Clay, had been accomplished. 



The condition of Central and South Greenland is, from Eink's map, 

 evidently that of a number of islands overwhelmed by land-ice, the 

 channels between which form the fjords through which this ice 

 issues to the sea ; and the cases of England and Greenland would be 

 identical, were it not that only the very narrow fringe of the archi- 

 pelago which skirts Davis Straits remains uncovered, whereas in 

 England the islands which remained uncovered were more extensive ; 

 and, owing to the more rocky character of Greenland, many of the 

 channels there are much deeper than were any of those in England, 



