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way to account for the transport of large angular erratics which 
are found in breccias of Permian Age. Mr. Godwin Austen 
called attention to ice action in France during the Carboniferous 
Period, owing to similar phenomena presented by carboniferous 
conglomerates or moraines. The 66 flysch ” of Switzerland indi- 
cates the existence of glaciers in the Swiss country during some 
part of the long Eocene Epoch, while during its earlier ages we 
know that the nummulitic ocean flowed over sites now elevated 
into the summits of the Diablerets and the Dent du Midi. So 
during the Miocene Epoch. In earlier Miocene times we find 
forests growing in the distant north ; while in later Miocene 
times, or during the deposition of Upper Miocene strata, we 
know there were Miocene glaciers which bore down great mo- 
raines to the neighbourhood of Superga, near Turin. Lastly, the 
retiring of the colossal glaciers which stranded the Pierre a Bot 
above Neufchatel was followed by a warm or interglacial period, 
with small glaciers ; and then the great glaciers came back again , 
and since that have again receded to the present pigmy ice- 
streams now presented to our observations. These are geological 
phenomena not to be ignored ; and without venturing to pro- 
nounce an opinion on the theories of Mr. Croll, I honestly 
confess many of them will, if they bear the test of criticism, 
prove a blessing if they enable us to solve some of the more 
puzzling phenomena presented by geology. 
Is it likely or probable, if there was frost and ice action in 
Scotland and England during Devonian and Permian times, and 
during the Carboniferous Epoch in France, that at the same 
period Polar regions were warm, and free from glacial action ? 
Again, Mr. Croll’s theory as to the oscillation of the level of 
the waters of the oceans, caused, as he believes, by the physical 
effects produced by recurring glacial phenomena, appears to 
account for some of those changes in the level of land and 
water which are so difficult to account for when we have to 
appeal solely to local earthquake movements — earthquake move- 
ments in all kinds of places in shifting the land up and down, 
and down and up again. Again, recurring glacial epochs through 
all past time would assist us somewhat in accounting for the 
extermination of whole series of animals, which, as the Frost 
periods recurred, might have been unable to survive, and 
during which some species, driven southwards, might have 
become changed and modified. No one can tell why the 
mammoth and woolly rhinoceros, which once inhabited Siberia, 
and later on temperate Europe, in such vast herds, should have 
died out so as not to have left a single specimen up to historic 
times, or why the horse and mastodon should have perished in 
North America. No one can say why no trilobite lived, at all 
events in these latitudes, through the Permian period, or why 
