562 Reports and Proceedings—Duke of Argyll’s Address. 
to our pride, but it seems to be strictly true, that the questions raised 
with respect to Pleistocene geology are by far the most difficult—I will 
not say the most insoluble—with which we are called to deal. Take 
this short list of these questions:—The coming on of the glacial age: 
the great submergence which unquestionably accompanied some portion 
of it; the coming in of the great Pleistocene mammalia; the destruction 
of them, and the breaking up of old surfaces and of old lines of drainage 
which again accompanied that destruction; the distribution of gravelsand 
of muds over the surface of the country—what a volume of difficulties 
are involved in this series of events, all either immediately preceding 
or accompanying the birth and the dispersion of mankind! Yet how 
various and how contradictory are the theories which are now being 
advanced on each and all of these questions! And are not many of 
these difficulties of interpretation directly due to the preconceptions 
and prejudices which the doctrine of uniformity has established in 
many minds, indisposing them to believe in particular kinds of change 
and movement, which they are pleased to consider as catastrophes, and 
disposing them, on the other hand, to invent other kinds of movement 
and of change, which, however violent, can be more easily conceived 
as slow? I shall now specify a few geological problems on which, as 
it seems to me, the prejudices and prepossessions of the Uniformitarian 
Theory have prevented or impeded the natural interpretation of patent 
facts. And first, with regard to the phenomena of the glacial period. 
I accept as one of the most certain conclusions of our science that 
there has been, very lately in the scale of geological time, a period 
when the climate in these latitudes was glacial. I live among the 
facts which prove this. I see them in profusion every day, and 
indications in abundance surround me in every walk and in every 
drive, showing most clearly the conditions under which the ice has 
worked. I have no time or space now to go into detail. Suffice it to 
say that ice has, in my opinion, worked among the Argyleshire hills in 
the two great forms of glaciers and of floating ice, and in no other 
form whatever. Moreover, the floating ice has worked at two different 
levels, mainly; one of these is at or within some thirty feet of the 
existing level of the ocean, the other is at a level high up the flanks 
of the hills, and as regards the lower ranges, especially over their very 
summits. As regards the first or lower of these two levels, probably 
there will be no dispute. But as regards the higher level, we come at 
once upon conclusions which do not fit easily and smoothly into the 
grooves of the uniformitarian hypothesis. It is, of course, one of the. 
most elementary conceptions of geology that the areas now occupied 
by mountains of sedimentary strata have been all, more or less often, 
in the position of sea-bottoms or the beds of lakes. But this is quite 
a different conception from that which supposes that our existing 
mountains have been lower to the depth of two, or perhaps three, 
thousand feet, and that along all their flanks and over their summits 
a glacial sea has sent its floe-ice and its icebergs, grating, grinding, 
smoothing, polishing, and finally stranding, upon every surface and 
protuberance which opposed itself to the prevailing tides and currents. 
It is quite certain that this glacial sea, if it ever existed, has not lett 
any evidence of a prolonged stay upon these mountain slopes. There 
