as carved in the solid land by the force of
pre-Adamite glaciers, or whether it is a Titanic cleft formed by the
breaking off of Greenland from Grant Land, is a question still
undetermined by geologists; but for difficulty and danger there is no
place to compare with it in the whole arctic region.

It is hard for a layman to understand the character of the ice through
which the _Roosevelt_ fought her way. Most persons imagine that the ice
of the arctic regions has been formed by direct freezing of the sea
water; but in the summer time very little of the floating ice is of that
character. It is composed of huge sheets broken off from the glacial
fringe of North Grant Land broken up by contact with other floes and
with the land, and driven south under the impetus of the violent flood
tides. It is not unusual to see there ice between eighty and one hundred
feet thick. As seven-eighths of these heavy floes are under water, one
does not realize how thick they are until one sees where a huge mass, by
the pressure of the pack behind it, has been driven upon the shore, and
stands there high and dry, eighty or a hundred feet above the water,
like a silver castle guarding the shore of this exaggerated and
ice-clogged Rhine.

The navigation of the narrow and ice-encumbered channels between Etah
and Cape Sheridan was long considered an utter impossibility, and only
four ships besides the _Roosevelt_ have succeeded in accomplishing any
considerable portion of it. Of these four ships, one, the _Polaris_, was
lost. Three, the _Alert_, the _Discovery_, and the _Proteus_, made the
voyage up and back in safety; but one of those, the _Proteus_, was lost
in an attempt to repeat the dash. The _Roosevelt_ had on the expedition
of 1905-6 made the voyage up and back, though she was badly smashed on
the return.

Going north, the _Roosevelt_ of necessity followed the coast a portion
of the way, as only close to the shore could any water be found which
would enable the ship to advance. With the shore ice on one side, and
the moving central pack on the other, the changing tides were almost
certain to give us an occasional opportunity to steam ahead.

This channel is the meeting place between the tides coming from Baffin
Bay on the south and from Lincoln Sea on the north, the actual point of
meeting being about Cape Frazer. South of that point the flood tide runs
north, and north of it the flood tide runs south. One may judge of the
force of th