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to say that the outcome of all the investigations hitherto made is, 
that these Boulder clays, sands, and gravels are due to ice-action ; 
that they were formed at a time when the countries where they 
occur were swathed in one mass of ice as Greenland is to-day. 
This is the general conclusion of geologists, but there are 
very great differences of opinion between them as to the precise 
manner in which the ice acted. Those differences arise mainly on 
the relative importance attached to the parts played by glaciers 
on the one hand, and by icebergs and floebergs on the other. 
My object at present is not to discuss the merits or demerits of the 
different views set forth by the numerous writers on the subject, 
but rather to place before you a number of relative facts which 
have come under my own observation in the course of numerous 
perambulations through West Cumberland. 
In looking at a section of sand and gravel, or of boulder clay, 
as laid open in a railway cutting, a stream side, or along the sea 
shore, almost the first thing that would strike a curious observer is 
the many different kinds of rock which it contains in the form 
of boulders. If he be well acquainted with the rocks in the im- 
mediate neighbourhood of the section, most likely he will be able 
to identify many of the boulders ; but there will almost certainly 
be a great many others which he cannot identify, unless he has 
travelled and observed far afield. Should he, however, happen to 
recognise some of the farther-travelled ones, doubtless a very 
curious train of thought will be aroused, and he will be greatly 
puzzled as to how those boulders have come to be where he sees 
them. Geologists who have made the matter a study, are agreed 
that they have been brought there through the agency of ice; but 
there is much difference of opinion as to the form of that ice, 
some contending that it acted as glaciers, whilst others are favour- 
able to icebergs and floebergs. Such being the case, it is somewhat 
remarkable that there should be so little known as there is 
regarding the distribution of boulders; for many boulders have 
such a distinct character, that it becomes possible to trace out 
almost exactly the course they must have taken in travelling from 
their parent rock to the position they now occupy; so that by 
