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district, form a heterogeneous assemblage of various rocks, mixed 

 in perfect confusion. It is natural that when local students meet 

 with such wonderful collections of rocks as are contained in the 

 Boulder Clay of this and the adjoining districts, that they should 

 endeavour to unravel the mysteries of their appearance, — the why 

 and the wherefore of their presence, their derivation, and the mode 

 of transit from their far-away homes to their present locales. 



Perhaps it would be impossible to find better opportunities 

 for studying these deposits than are presented on this north-western 

 coast. Here we find a stiff hard clay enclosing these various 

 rocks, which are usually more or less sub-angular, and not un- 

 frequently are scratched in a peculiar manner — the well-known 

 glacial striae. There is no regularity in the deposition of the 

 beds, large and small stones are mixed heterogeneously together 

 without, in the typical deposits, any stratification or bedding in 

 them or the clay. Water has undoubtedly been the motive power 

 that has brought together these various materials ; but water as 

 water has a wonderful sorting faculty. The fine particles are 

 carried farthest, the coarser portions to a less distance, whilst 

 larger blocks travel but a little way comparatively from their parent 

 home, until from some cause or other they are broken up, and 

 their constituent parts travel farthest in inverse proportion to their 

 size. Water as water cannot have laid down a deposit of the 

 finest mud interspersed with huge boulders. We are therefore 

 driven to assume that ice must have been the proximate cause of 

 the formation. This explanation, however inevitable, by no means 

 clears away our difficulties ; we are but landed amongst phenomena 

 which are in general most difficult of elucidation, and in many 

 cases have as yet received very unsatisfactory solutions. 



When the glacial origin of these deposits was first surmised, 

 it was, I believe, generally assumed that they were the remains of 

 icebergs which had melted in the respective localities. But this 

 hypothesis proved highly unsatisfactory. It required immense 

 depressions of the land to allow of the flotation of the icebergs, 

 which in many instances could scarcely be granted. Icebergs in 

 general contain an infinitesimal proportion of debris, quite in- 



