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32 IITMERSION OF ICE-MASSES. BOULDERS.
pact and clear in its texture, and to be heavier than the ordinary pack-ice,
bulk for bulk,—the difference I have referred to, namely in the ratio between
1 to 14 and 1 to 16, being, I conceive, wholly attributable to accidental differences
in the solid contents of the submerged and exposed portions. Thus,
in a small berg which was stranded at the head of one of the fiords, I found the
ratio of submergence to elevation to be only 7 to 1 ; but the cause of this
decreased ratio was manifest, inasmuch as the portion above water rose up to
an angular peak, whereas from the water-line, as deep as the eye could penetrate
into the clear water, the berg retained its dimensions. As it was aground close
to the shore, I was enabled to measure the height of its summit by scrambling
up the hill-side adjoining, and 1 found it to be a little above 40 feet. The
water immediately around it, as measured by a plummet, was somewhat more
than 50 fathoms. At the period of the tide at which I inspected it, the line of
floatation was 6 feet from the surface of the fiord. But it was parallel to it, and
it is therefore unlikely that the berg could have been resting on a boulder or
rock elevated above the general level of the bottom. Assuming, then, as the
appearances warrant, that the solid contents of the 40 feet above water were
equal to half the solid contents of a like number of feet below water, we should
have a ratio of 1 to 15, or the mean of that established by actual measurement.
I have alluded to the presence of boulders in the fiords adjoining the anchorage
at Goodhaab. From the clearness and stillness of the water, it was often possible
to observe the bottom, near the shore-line, at considerable depths; and I was
sorely puzzled to account for the smooth rounded look of the greater portion of
these stones. I t was evident these could not have been subject to the action of
waves, from the depth at which they lay. There was no glacier in the vicinity
to which their presence and figure might have been attributable. Nor did it
seem probable that such a unifonn distribution could have been effected by
icebergs or ordinary drift-ice which had brought them from distant localities.
On examining the character of those occurring near low-water mark, I found it
corresponded with the rock-formation of which the surrounding heights was
composed. But as the same kind of formation is said to prevail along the
greater portion of the west coast of Greenland, both to the north and south, it
offered no satisfactory explanation as to the origin of the boulders in the present
locality.
FORMATION OF BOULDERS.
At the south-eastern angle of the large fiord to the southward of the anchorage,
I found not only that these boulders were congregated together in unusually
large quantity, but that they formed a sort of moraine, extending along a valley
which ascended for about 2000 feet up the mountain. Following this valley to
its crest, I arrived at a tarn of nearly a mile in diameter, occupying an amphitheatre
the whole of which, with the exception of the part next to the fiord, was
bounded by a precipitous escarpment. The height of this could not have been
less than 1000 feet. Its face seemed to be cut up into innumerable channels, as
if by the overflow of torrents at its upper margin; but water was only streaming
down a few of these, and apparently in no great volume. The margin of the
tarn was perfectly level all round, and occupied the entire area of the amphitheatre
thus formed. As the water was only about a foot and a half in depth,
and its temperature, comparatively speaking, warm from the absence of ice, 1
waded in for some distance, and found that the bed consisted of nothing but
an accumulation of boulders, all more or less perfectly rounded. From the
appearance of the valley, the remains in it of enormous boulders of quartz-rock,
some of which are 15 feet in diameter, and the polished and, in places, furrowed
surfaces of the schistose rock which constitutes the bed of the valley
itself, it would seem probable that this had once been occupied by a glacier,
and that the masses of rock detached from the escarpment on the melting
of the snows are worn down into their present form during their transit across
the flat bed of the tarn and ultimately carried along by the torrents to the
fiord below. Once arrived there, and deposited in a gradual slope, the ice formed
in the winter would bear them away and distribute them over the bottom.
A curious corroboration of the perpetual grinding to which the boulders in
the tarn are subject is derived from the fact that not a trace of any of those
microscopic alg«, or lower animal forms, with which the surfaces of smooth
stones are invariably encrusted, even in streams running with considerable velocity,
could be scraped off with a knife; whereas in some small rocky pools situated on
the slopes of the lower hills, I met not only with Coiifervie, but Diatoms growing
in great profusion, and between twenty and thirty species of Desmidiace®.
Aug. 13.—From infancy the Esquimaux is taught to regard the sea as his
special domain, and to look to it as his great store-house for food, for clothing,
and, in short, for everything that is absolutely essential to his existence.
F