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added to the mass behind, so that the glacier moves slowly down the 
valley, grinding out its bed, and constantly replenished from behind. 
Rocks and stones of all sizes continually fall from the neighbouring peaks 
on to the surface of the glacier, many slip into the abundant fissures, and 
thus get under the huge mass of ice, which, as it slides along, scores and 
scratches them, and also causes them to scratch the rock which forms the 
glacier-bed. When the glacier reaches a lower level it melts, and conse- 
quently deposits its freight of stones. As the glaciers are persistent, large 
heaps of stones are thus formed, which glaciologists term “ terminal 
moraines.” In consequence of the increase of temperature, the glacier at 
its lower extremity is much thinner, and wears away less rock than it 
does nearer its source ; and thus a curved basin is formed, in which the 
glacier terminates. Now Professor Ramsay shows us that the great lakes 
of Switzerland are all situated in such basins as these, formed by great 
glaciers whose beds can be traced up the mountain valleys, which existed 
when the North of Europe was in a much colder condition than at present. 
In the same way he demonstrates to us that many of our Welsh and 
Scotch lakes have been similarly formed ; for in the mountain valleys of 
Scotland and Wales we find the scratched stones, the furrowed rocks, and 
the “ moraines,” which are undoubted evidence of the existence, in these 
valleys, of glaciers. At, the extremities of these valleys are the lakes, for 
the existence of which Professor Ramsay thus accounts. He does not, 
however, tell us how the trout got into these lakes, as it does not come 
under this branch of science ; but the question is one of some interest, 
and is, we believe, rather a knotty point for Darwinians to work out. The 
Drift period, in which our island was covered with an ice-bound sea, is 
fully discussed in another lecture, and the well-known bone-caves and 
their fierce inhabitants are described. The silts and gravels of river 
valleys, and the flint hatchets of the Somme deposits, occupy a part of 
the lecture. We are sorry M. de Perthes’ fossil jaw was not brought to 
light in time for Professor Ramsay’s course, otherwise we might have had 
his opinion as to its claim to belong to a “ real fossil man.” 
In his last lecture Professor Ramsay points out the influence which the 
geological structure of Britain has had upon its population, its manufac- 
tures, and general welfare. He shows how the mountainous parts of our 
country have formed a refuge for the ancient conquered tribes of Britain ; 
how the coal-fields have centered around them an active and thriving 
population, engaged in manufacturing pursuits ; and how the irregular 
contour of our coast has given rise to our great seaport towns. As to 
how and when man came, to this part of the world, Professor Ramsay 
says : “We know that these islands of ours have been frequently united 
to the continent, and as frequently disunited, partly by elevations and 
depressions of the land, and to a great extent also by denudations. When 
the earliest human population reached their plains, they were probably 
united to the continent. Such is the deliberate opinion of some of our 
best geologists.” He is able, in conclusion, to rejoice as a true philosopher 
over our present condition as an island : “ We are happy, in my opinion, 
above all things in this, that by denudation we have been dissevered from 
the continent of Europe ; for thus it happens that, uninfluenced by the 
