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the material of moraines of probably decaying glaciers having been 

 shifted and arranged by strong streams of water running there- 

 from ; hence they are said to have been formed by fluvio-glacial 

 agency. Scattered blocks (" erratic "), brought from a distance 

 and left on the melting of the ice, and morainic accumulations 

 left in mountain-valleys, come in the same category as the above. 



Lakes and rock-basins occupy Chapters XVIII. and XIX. 

 Several modes of origin are known for lakes, and some are briefly 

 mentioned here. For lakes in the supposed ice-ploughed hollows 

 in solid rock, a favourite subject with his friend the late Sir 

 Andrew Eamsay, Prof. J. Geikie advances all the evidence he can, 

 ignoring what has been brought forward and published to the 

 contrary. 



Chapters XX. and XXI. explain that other superficial deposits 

 later in age than the "upper till" were brought about by the 

 existence of " district ice-sheets and local glaciers," belonging to 

 Dr. J. Geikie's " third glacial epoch " (p. 283). These, he thinks, 

 succeeded " interglacial " conditions, and were locally coincident 

 with some shelly deposits on the sea-board, especially along the 

 Firths of the Clyde and Forth. It is to this period that the 

 Author now refers the origin of the " parallel roads of Glenroy " 

 by the intervention of the great western ice crossing the neigh- 

 bouring valleys lower down and thereby causing lakes, as first 

 suggested by Agassiz, and subsequently defined by Jamieson and 

 Prestwich (p. 283). 



Later formations, either within, or just subsequent to the 

 Glacial Period are noted in Chapters XXII. & XXIII., as peat- 

 bogs, raised beaches, sand-dunes, river-terraces, and old lake-beds, 

 bearing recognizable evidence of their relative age, contemporary 

 with a partial submergence of the land ; and with a cold climate, 

 destructive of the forests and giving rise to some highland glaciers. 

 A repetition of the foregoing or similar conditions ; and then the 

 last elevation of the land, and the arrival of the present state of 

 things, constitute part of the eleven successive changes, from the 

 " lower till " to the existing land and sea, succinctly enumerated 

 at page 325, so far as Scotland is concerned. 



"We are now led to the consideration of glacial phenomena met 

 with (1) in England and Ireland ; (2) Northern Europe : (3) 

 Central Europe ; (4) the Alps, and other parts of Europe, in 

 Chapters XXIV. to XXXVI. This last chapter enumerating five 

 glacial epochs, each with its interglacial epoch, brings us to 

 present or, rather, prehistoric times, and comprises long periods 

 during which Man has existed in this part of the World. 



The last or *"' present" epoch (p. 612) was " marked in Britain by 

 the retreat of the sea to its present level, and by the return of 

 milder and drier conditions, and . the final disappearance of 

 permanent snow T -fields." 



The Author arranges the "glacial succession " in the British 

 Islands as follows (beginning with the lowest) : — 



