78 NOTES ON A SUMMER TOUR IN NORWAY. 
and a uniform elevation of the land would convert them into fresh- 
water lakes of great depth. In some of our Highland lochs the 
depth of the loch exceeds that of the sea at its mouth by some 
400 or 500 feet, but in Norway the difference is very much 
greater. There are, in fact, parts of the Sogne-fjord which have 
a depth of over 3,000 feet below that of the sea bottom 
immediately at the mouth of the fjord. 
It is not only the sea lochs and fjords which lie in such deep- 
cut hollows as this, but many of the fresh-water lakes are found 
occupying similar depressions. 
Two theories have been advanced to account for these remark- 
able facts. The first is that the extraordinary deepening of the 
portion of the submerged valley now occupied by the fjord has 
been produced by differential subsidence due to earth movements ; 
the second is that the deep rock basins owe their origin to the 
erosive power of ice. 
The theory of subsidence, when tested by the actual facts, is, I 
think, quite untenable, for it is impossible that such enormous 
displacements should have taken place in the bottoms of the 
narrow fjords without leaving abundant evidence in the crumpling 
and faulting of the rocks which bound their sides, and evidence 
of this kind is altogether wanting. 
It is now about thirty years since Professor Ramsay pointed 
out that lakes occupying rock basins are exceedingly numerous 
only in those countries which have been largely under g/acta/ action, 
the number of such lakes being in some measure proportionate 
to the amount of ice action which can be traced. Ramsay 
attributed the formation of such lakes and sea lochs, not to 
subsidence or elevation of the ground, but to the actual erosion of 
their basins by glaciers. 
“‘ Now, no grander display of ice action can be seen than that 
which the fjords and fjord valleys of Norway present. The 
smooth and mammillated mountain slopes, the rounded islets that 
peer above the level of the sea like the backs of great whales, 
the glittering and highly polished faces of rocks that sweep 
right down into deep water, the great perched blocks, ranged 
