810 B. N. PEACH AND J. HORNE ON THE 
ice-sheet, which must have coalesced with the Scandinavian mer de 
de glace in the North Sea. That this union must have taken place 
is evident from the proofs of the deflection of the glaciers along the 
eastern sea-board of Scotland and England ; and it would even now 
appear that the great Chalky Boulder-clay of East Anglia is a pro- 
duct of land-ice which moved inland in a north-east and south- 
west direction. ‘These phenomena point to the existence of some 
constantly opposing force which was capable of overcoming the 
seaward motion of the Scotch and English glaciers. In other 
words, the two ice-sheets must have united on the floor of the 
North Sea, one great outlet for this ice-field being towards the 
north-west by the Pentland Firth and the Orkney Islands. When 
the Orkney Islands are examined in detail they will doubtless yield 
conclusive evidence in support of this north-west movement. 
After the mer de glace had ceased to be confluent with the local 
glaciers of Shetland, the latter lingered on for a time, filling all the 
main valleys and flowing off the land in all directions. The deposits 
met with on the eastern coast of the Mainland between Lerwick 
and Boddom, and again between Colifirth Voe and Fethaland Point, 
must be attributed to this local movement; while the numerous , 
moraine heaps sprinkled over the valleys indicate the immense 
quantity of débris which must have been borne downwards on the 
surface of the small glaciers. 
4, Absence of Gravel Kames and Raised Beaches in Shetland — 
Throughout the isles we searched in vain for those ridges of gravel 
which form such a notable feature in Scotland. Here and there the 
moraine mounds and the moraine débris, which is spread irregu- 
larly over the slopes of the hills, show signs of rude stratification, 
while the stones are more or less waterworn; but no one would 
readily mistake them for true kames. Moreover there is a 
remarkable absence of raised beaches indicating changes in the 
relative level of sea and land. Though we examined the islands 
with considerable minuteness, we never found a trace of those 
familiar terraces which are so characteristic of parts of the Scotch 
coast-line. This is all the more remarkable, as the voes or sea- 
lochs are admirably adapted both for the formation and preservation 
of sea-beaches. We cannot help believing that, if such deposits had 
been formed, we must assuredly have met with some indications of 
them; and for this reason it seems just to infer that they never ex- 
isted in Shetland. The remarks made by Professor Geikie in an 
article in ‘ Nature’* clearly show that their absence has an important 
bearing on the question of their origin. For if they be due, as 
Dr. Croll suggests, to the rise of the sea-level, owing to an accumula- 
tion of ice round the North Pole during the glacial period, then we 
should naturally expect to find them in localities which are so well 
adapted for their formation; but since this is not the case, we 
may infer that they indicate pauses in the gradual elevation of the 
land which must have been general over the whole of Scotland in 
postglacial times. It would seem, however, that Shetland did not 
participate in these general movements of upheaval. 
* ‘Nature,’ vol. xvi. p. 414. 
