696 PROCEEDINGS OF THE GEOLOGICAL society. [June 22, 
Treland, ‘‘ Oscars ” in Sweden); so that, unless this stumbling-block 
be removed, we must consider them due to fresh-water action—this 
action being still unknown. ‘The mounds on the “ Mound Prairie” 
in Washington territory’, and also in Texas, are, I am convinced, 
very similar in their origin, though I doubt if the cause, or causes, 
engaged in forming them were in any way connected with the glacial 
period. My eminent friend Professor J. D. Whitney’s denial? of the 
presence of the glacial drift on the North Pacific coast (whatever 
may be said of the region he is personally intimately acquainted 
with, as Director of the Geological Survey of California) is founded, 
as far as British Columbia, Washington Territory, and Vancouver 
Island (so far as I have examined these countries) are concerned, 
on the imperfect observation of his informant*, the drift being 
everywhere well developed in these regions, as I have pointed out 
in another place*. 
4, Boulders.—Boulders scattered over the country are due to 
the period of the formation of the (non-fossiliferous) Boulder-clay 
when the country was sunk more than now, as will be afterwards 
noted in the inferences (§ 3); but those lying in the lines of valleys 
are due to the depositing power of kergs, as these bergs still, as 
described, deposit them in the originals of these glens and valleys, 
the Arctic fjords; and hence the boulders keep the lines of the 
valleys. The boulders and travelled blocks on the top of the 
highest hills are due chiefly to the transporting power of the great 
moving “inland ice” of Britain at that period; and the former are 
really a portion of the moraine profonde, which, however, the old 
rivers (derived from the melting of the glacier-cap) or the subsequent 
action of the weather have not swept, with the clay around them, 
into the valleys. These boulders, dragged over the rocks, would 
act as a file to the underlying strata they came into contact with; so 
that we need not ‘be surprised that both the rocks and boulders are 
deeply furrowed. 
We must, however, draw a distinction between the different 
kinds of blocks seattered over the country. Those blocks, rounded, 
grooved, and worn as if by ice could (in my opinion) be only due to 
this moraine profonde, and are connected with the superincumbent 
inland ice. The boulders &c. carried off by bergs are not grooved 
or worn; for they merely drop down on the upper surface of the 
ice and are carried out to sea, and there dropped. If they are 
afterwards grooved it must be by the action of ice passing over 
them and grazing them—an occurrence, I fancy, not very common. 
That these erratic blocks will get water-worn is only a natural con- 
' Gibbs, in ‘ Pacific Railroad Surveys,’ vol. i. pp. 469 & 486 ; Cooper, in the 
‘Natural History of Washington Territory,’ p. 18. These and other physico- 
geographical features of North-West America will be more fully described in the 
author’s ‘ Hore Sylvanz’ now in course of publication. 
> Proceedings of the California Academy of Sciences, vol. iii. p. 277 (1866). 
3 See also Dall, in ‘Silliman’s American Jour. of Se.’ Jan. 1868, and Proe. 
Boston Nat. Hist. Soc. vol. xii. pp. 145, 146. 
+ Petermann’s ‘Geographische Mittheilungen,’ 1869, p. 5; Trans. Geol. Soc. 
Edin. 1869, p. 19; and ‘Silliman’s Amer. Journ. of Se.’ Noy. 1870, pp. 318-324. 
