172 
ISLAND LIFE. 
[part I. 
angular blocks of serpentine and greenstone often of enormous 
size, one being fourteen feet long, and another twenty-six feet. 
Some of the blocks were observed by Sir Charles Lyell to be 
faintly striated and partly polished on one side, and they are 
scattered through the beds for a thickness of nearly 150 feet. 
It is interesting that the particular bed in which the blocks occur 
yields no organic remains, though these are plentiful both in 
the underlying and overlying beds, as if the cold of the icebergs 
had driven away the organisms adapted to live only in a com- 
paratively warm sea. Rock similar in kind to these erratics 
occurs about twenty miles distant in the Alps. 
The Eocene period is even more characteristically tropical in 
its flora and fauna, since palms and Cycadaceae, turtles, snakes 
and crocodiles then inhabited England. Yet on the north side 
of the Alps, extending from Switzerland to Vienna, and also 
south of the Alps near Genoa, there is a deposit of finely- 
stratified sandstone several thousand feet in thickness, quite 
destitute of organic remains, but containing in several places 
in Switzerland enormous blocks either angular or partly rounded, 
and composed of oolitic limestone or of granite. Near the Lake 
of Thun some of the granite blocks found in this deposit are of 
enormous size, one of them being 105 feet long, ninety feet wide, 
and forty-five feet thick 1 The granite is red, and of a peculiar 
kind which cannot be matched anywhere in the Alps, or indeed 
elsewhere. Similar erratics have also been found in beds of the 
same age in the Carpathians and in the Apennines, indicating 
probably an extensive inland European sea into which glaciers 
descended from the surrounding mountains, depositing these 
erratics, and cooling the water so as to destroy the mollusca 
and other organisms which had previously inhabited it. It is 
to be observed that wherever these erratics occur they are 
always in the vicinity of great mountain ranges ; and although 
these can be proved to have been in great part elevated during 
the Tertiary period, we must also remember that they must 
have been since very much lowered by denudation, of the 
amount of which, the enormously thick Eocene and Miocene 
beds now forming portions of them is in some degree a measure 
as well as a proof. It is not therefore at all improbable that 
