Paleo-Geological and Geographical Maps of the British Islands. 295 
broken up into rafts and bergs answering in all respects the description given of the 
phenomena in England and Ireland.* 
The local moraines which existed amongst the higher unsubmerged districts, 
became centres of dispersion of erratics which were floated to their destination on 
masses of glacier ice. If (as Dr. Geikie considers) about the time now referred to, 
the south of Scotland was submerged to the depth of 1,100, or even 1,250 feet,+ and 
the north of England and of Ireland to a depth of about 900 or 1,000 feet, the 
tract submerged would be very large, and boulders would be carried in directions 
corresponding to the prevalent winds and currents. The courses travelled by such 
erratics have been ably traced by, amongst others, Mr. D. Mackintosh, who has 
traced the boulders over large tracts of country in the north-west and centre of 
England and Wales to their parent masses. Amongst the more remarkable 
instances of erratic blocks are those at Pagham and Selsea, mentioned by Lyell.§ 
It is unnecessary for my present purpose to go more fully into the details of later 
glacial and post-glacial phenomena. It will probably suffice that I should add that the 
climaticand geographical conditions of the stage of the Upper Boulder Clay gradually 
gave place to those which preceded, and ultimately introduced the existing temperate 
condition of climate. The land gradually rose out of the sea, the rise being 
probably accompanied by prolonged pauses. The snows and glaciers melted off the 
mountains. The sea was gradually freed from ice, and the waters became pure and 
limpid. The plants and animals of the adjoining continent once again flocked over 
and restored life and verdure to the face of nature. _ Man, himself, followed in their 
train, and made his dwelling in the caves of the rocks, living by the chase, and 
trying his strength with some of the-fierce carnivores which infested the forests and 
dens of the mountains.|| With this state of affairs geology closes its record, and 
makes way for the researches of the antiquarian and historian. 
It will be observed that in the maps referring to the glacial period (Plates 
XXXIV. and XXXV.) I have represented only the supposed physical restorations 
of the surface of the country as they were during the three special stages to which 
they point. Ihave not attempted to produce corresponding maps showing the 
distribution of the various glacial deposits. To attempt this would have been 
impossible on a scale so small as those of these three little maps, even if I had had 
the necessary materials to guide me. But such is not the case. The mapping of 
* Dr. Geikie, andalso Mr. Jamieson (Quart. Journ. Geol. Soc., 1865) have treated very fully of the 
formation of kames (in Ireland called “eskers”), which the former refers to the upper glacial deposits, 
but I prefer (for reasons I have stated elsewhere, “ Phys. Geol. of Ireland,” p. 100) to regard them as 
post-glacial. The phenomena in Ireland are very similar to those of Scotland. 
+ From Mr. H. M. Skae’s observations in Nithsdale. 
{ Quart. Journ. Geol. Soc., London, 1879-82. § “ Antiquity of Man.” p. 280. 
|| I place the advent of man as post-glacial deliberately, as Mr. John Evans, F.R.S., our highest 
authority on such questions, has recently analysed the evidences which have been adduced both in Europe 
and the British Isles, for assigning to him a pre-glacial advent, and finds them in all cases more or less 
untrustworthy. 
