ers, discharging at the heads of
the long arms of Holkam Bay. At the head of the Tahkoo Inlet, still
farther north, there is one; and at the head and around the sides of
Glacier Bay, trending in a general northerly direction from Cross Sound
in latitude 58 deg. to 59 deg., there are seven of these complete glaciers
pouring bergs into the bay and its branches, and keeping up an eternal
thundering. The largest of this group, the Muir, has upward of 200
tributaries, and a width below the confluence of the main tributaries of
about twenty-five miles. Between the west side of this icy bay and the
ocean all the ground, high and low, excepting the peaks of the
Fairweather Range, is covered with a mantle of ice from 1000 to probably
3000 feet thick, which discharges by many distinct mouths.

[Illustration: MOUNT RAINIER FROM PARADISE VALLEY--NISQUALLY GLACIER.]

This fragmentary ice-sheet, and the immense glaciers about Mount St.
Elias, together with the multitude of separate river-like glaciers that
load the slopes of the coast mountains, evidently once formed part of a
continuous ice-sheet that flowed over all the region hereabouts, and
only a comparatively short time ago extended as far southward as the
mouth of the Strait of Juan de Fuca, probably farther. All the islands
of the Alexander Archipelago, as well as the headlands and promontories
of the mainland, display telling traces of this great mantle that are
still fresh and unmistakable. They all have the forms of the greatest
strength with reference to the action of a vast rigid press of
oversweeping ice from the north and northwest, and their surfaces have a
smooth, rounded, overrubbed appearance, generally free from angles. The
intricate labyrinth of canals, channels, straits, passages, sounds,
narrows, etc. between the islands, and extending into the mainland, of
course manifest in their forms and trends and general characteristics
the same subordination to the grinding action of universal glaciation as
to their origin, and differ from the islands and banks of the fiords
only in being portions of the pre-glacial margin of the continent more
deeply eroded, and therefore covered by the ocean waters which flowed
into them as the ice was melted out of them. The formation and extension
of fiords in this manner is still going on, and may be witnessed in many
places in Glacier Bay, Yakutat Bay, and adjacent regions. That the
domain of the sea is being extended over the land