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as those of the Gareloch, discovered by Mr Maclaren, and those of 

 Loch Lomond and Loch Katrine, discovered by himself, as well as 

 those of the valley of the Forth, may all be classed under the earlier 

 and more general glaciation, though not perhaps in any place free 

 from some interferences of the later and more local movements. He 

 asserts that every part of the Highlands, and much of the Lowlands, 

 bear traces of this general glaciation, in the rounding and smoothing 

 •of rocks, though in many instances, the effects are comparatively ob- 

 scure, in consequence of weathering, and the washing of the rock- 

 surface by superficial accumulations. The author indicated a new 

 kind of memorial of these glacial operations, in what he described as 

 MouldingSy seen on the sides of many hills in Scotland, generally 

 nearly horizontal, resembling the mouldings produced in wood by the 

 use of a curve-edged plane, and which he considers as connecting them- 

 selves on the one hand, with such longitudinal ridges as the Garleton 

 Hills, all lying in the direction of the striation of the^district ; and, on 

 the other, with the rounded and flowing outlines of such larger hills as 

 the Pentlands, on which they are themselves marked. The whole phe- 

 nomena, in the opinion of the author, demand the passage, over large 

 areas of unequal country, of some agent at once plastic and fitted 

 to apply with keen abrading force to the surface ; at the same time 

 in such volume as to fill valleys several miles in breadth, and from 

 one to two thousand feet in depth. He contended that, as respects 

 all these glacial phenomena, Scotland is in precisely the same condi- 

 tion as Scandinavia, where there are proofs of a general movement 

 from the north-west, though turning easterly in the southern district ; 

 the valleys on the shores of the Northern Ocean, and White Sea, which 

 shewed proofs of glaciation in the seaward direction, being seats of 

 comparatively modern and local glaciers. The same doctrine applied 

 to North America. 



In speculating on the nature of the agent, the author could not 

 profess to speak with much confidence ; but he thought that, in dis- 

 missing the disproved Dilatation Theory of Charpentier and Agassi z, 

 it would be well to keep in view, that there was no theoretical objec- 

 tion to a flow of glacier ice over wide areas of small inclination, if the 

 latter circumstance were compensated by the volume of the mass ; 

 and it even appeared that, on the hydrostatic principle, an accumu- 

 lation of the materials in one quarter, would cause a movement to- 

 wards any other quarter offering sufficiently small resistance. The 



