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will be carried with considerable speed by steep glaciers to the sea; the localized erosion will be very energetic; and we will get the fiords and the lakes—while the eroded matter will only be deposited before the glaciers as terminal moraines and terraces.

As the ice shed will be rather near the coastward margin of the inland ice, it follows that it is for a great part the enormous snowfall on the great western glacier's own surface which is to be transported. Hence these glaciers can follow more irregular lines from the first, only deepening and widening the preëxisting valleys, and so we get the complicated fjord systems; while, on the continental side, where a more uniform vis a tergo pushes the ice plate forward, the eroded depressions must be more regular. It is quite necessary to keep in view this great contrast between erosion and deposition on the part of the continental and the coast sides of the great ice sheets, respectively, in order to be able to understand many of the complicated glacial phenomena.

We have seen that the deuteroglacial and especially the epiglacial inland ice had its ice shed far to the east from the watershed. Across this divide the ice must move and with somewhat accelerated speed in the narrow defiles. There must here originate passes or gaps (skar in Norwegian) across the watershed. Of these, we really have very many in Norway with a development in distinct relation to the distance between the ice-shed and the watershed and to the greatness of the epiglacial lakes and valleys on both sides. In not a few we have lakes with outlets on either side.

When the ice stream through such a gap came out to the western edge of the high plateau, there resulted a sort of ice cascade, which, like a waterfall, receded with rather great speed. These receding icefalls evidently gave origin to most of our fjord-valleys, sack-valleys, culs de sac interior to the fjord heads. Also these must generally be of deuteroglacial origin, as only then the ice flowed in great streams across the watershed.

The epiglacial stage of the deuteroglacial period must have had a very abrupt termination. The glaciers retired from the