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a nearly vertical wall of ice, perhaps 150 or 200 feet high. The main
glacier is formed by the union of five independent streams, which pour
down from an extensive ice cap to the north of the Garfield range and
south of the United States mountains. A tributary from the west joins
the main glacier about four miles above its terminus, and a second and
third tributary comes in from the northeast about seven and ten miles,
respectively, inland. The main glacier is separated from the lowest tribu-
tary by a rounded mountain spur, which from the station occupied by
the explorer cut off the view in that direction. In all other quarters,
however, the view was unobstructed, and embraced about 13 degrees
of azimuth.

The descriptions and sketches published by Greely seem to show that
the United States mountains are covered with a general neve field through
which the higher peaks project, and that large glaciers, resembling most



132 GLACIERS OF NORTH AMERICA.

nearly those of the alpine type, descend from the snow-covered uplands
in various directions. The ice streams flowing southward are the best
known, although but hastily examined, as explorations have been carried
nearest to the mountains in that direction.

Keports by Lieut. J. B. Lockwood and Serg. D. L. Brainard 1 of
explorations across Grinnell land from Archer fiord on the east to Greely
fiord on the west, show that the land both to the north and south of the
route followed is heavily covered with snow fields and glaciers. The
region to the south, especially, is mountainous, and the higher peaks and
domes alone reveal their forms above the all-pervading snow fields. From
this elevated neve a vast glacier or series of more or less confluent
glaciers, named " Mer de Glace Agassiz," flows northward, and, breaking
into individual ice streams, send out branches, some of which become tide-
water glaciers on reaching Greely fiord. The most remarkable feature of
the glaciers seen by Lockwood and Brainard, as in the case of the Henri-
etta Nesmith glacier, is the precipitous manner in which the ice ends.
The glaciers seem to terminate on the land as abruptly as do tide-water
glaciers in more southern latitudes on entering the sea. The long line
of ice cliffs marking the northern margin of Mer de Glace Agassiz is
termed the "Chinese Wall" in the report referred to, and, as shown in
sketches, when seen from the north present the appearance of a vast wall
of ice trending across the country in a general east and west direction,
and forming an escarpment apparently two or three hundred feet high.
Rising beyond this wall of ice, and seen over its crest, are the snow
fields and bald, snow-covered mountains where the great glacier has
its source.

From what is known of Grinnell land it appears that the glaciers
covering its more elevated portions are of the alpine type, but differ from
the glaciers in the mountainous portions of more southern lands for the
reason that their gathering grounds are comparatively low, and also
because the snowfall is light and melting greatly retarded. The result is
that glaciers of great size are formed in regions but little elevated above
the sea, and that, from some combination of conditions not yet fully
explained, they end abruptly in precipitous escarpments. 2

1 In "Report of the Proceedings of the U. S. Expedition to Lady Franklin Bay," by
A. W. Greely, Washington, 1888, vol. 1, pp. 274-296.

' 2 Since this book was written, Prof. T. C. Chamberlin has made a study of some of the
glaciers of Greenland, and has suggested that the low angle of incidence of the sun's rays in
the far north may explain the peculiar manner in which the glaciers there terminate.



GLACIERS IN THE GREENLAND REGION. 133

The general climatic and topographic conditions characterizing Grin-
nell land seem to extend southward and embrace neighboring land areas,
but explorers have yet to discover the limits of the glaciers in that region,
and to make more critical studies of the entire glacial system of the north-
eastern corner of the continent.



GREENLAND.

While the northern shore of Greenland remains unexplored it will be
impossible to determine the full extent of the land or of the ice sheet
covering it. From the most reliable data available, however, it is probable
that the land is about 1500 miles long from north to south, and 800 miles
broad in the widest portion. As estimated by Lieut. R. E. Peary, its
area is approximately 750,000 square miles, of which fully 600,000 are ice
and snow covered.

The interior of Greenland is reported by the few bold explorers who
have crossed it to be completely buried beneath a featureless plain of
snow. This covering has reached such a depth in all of the central part
that not a single mountain peak is known to break the even monotony of
its surface. The snow is highest and probably deepest in the central area,
and descends toward the coast, thus giving the island a convex surface.
The general elevation of the central portion is from 7000 to 8000 feet,
decreasing gradually toward the coast, especially to the east and west, where
the glaciers, protruding like great tongues of ice from the central region,
come down to the sea. The only mountain peaks that rise above the
surface of the general covering of snow are within from 50 to 75 miles of
the coast. These partially buried peaks rise like islands in the sea of
white. They are known to the inhabitants of the coast as nunataks; a
convenient name that has found a place in geological literature.

The depth of the nearly universal covering of snow and ice under
which Greenland is buried cannot be told, as it is impossible to determine
the topography of the land beneath. The best estimates that can be made
place its depth at several thousand feet. * In the central portion, where
the covering is apparently thickest, its depth may be fully equal to the
height of the surface above the sea, or about 8000 feet.

Like the neves of smaller glaciers, the surface of all the central part
of the Greenland ice sheet is composed of light granular snow. This
greatest of all neves in the northern hemisphere is remarkably uniform in
contour and unbroken by crevasses and unscored by water courses in all



134 GLACIERS OF NORTH AMERICA.

of its central area. The ice formed beneath the neve in the interior flows
outward in all directions through the passes in the mountains in independ-
ent ice streams, many of which reach the ocean and form the largest tide-
water glaciers known, with the exception of those in Antarctic regions.
One of the grandest of these tongues of ice is the Humboldt glacier, which
flows westward and discharges into Kane basin in about latitude 79 30'.
The extremity of this glacier, explored and named by Dr. Kane, forms a
wall of ice that is reported to be 40 miles long and from 200 to 300 feet
high above the sea. The veritable mountains of ice that break away from
the partially submerged face are of astonishing dimensions, and in many
instances find their way southward through Baffin's bay to the banks of
Newfoundland, and endanger the safety of trans-Atlantic steamers.

At many localities about the borders of Greenland, the rough, broken
extremities of glaciers similar to Humboldt glacier are known to enter the
sea. The adjacent waters are crowded with bergs shed off by these tide-
water glaciers, and also with floe ice originating from the freezing of sea
water. In numerous instances the tide-water glaciers end at the heads of
deep fiords, as in the case of many Alaskan glaciers. Again, the ice
terminates on land and presents steep, broken surfaces, that are so deeply
gashed and so shattered into pinnacles and spires that it is impossible to
cross them. When the topography of the high lands bordering the coast
is not favorable to the formation of tongue-like glaciers in deep valleys,
the ice from the great interior reservoir presses outward and terminates
in blue cliffs high up on rocky slopes, but melts before descending to the
sea. The rocks now bordering the glaciers, and in part confining them,
are in many localities rounded, smoothed, and striated, showing that in
former times the ice inundations were much more extensive than at
present, and reached the sea on every hand. In other localities, as
recently determined by Chamberlin, the land near the west coast has
never been ice-covered. A small driftless area on the shore of Ingerfield
gulf is one of the most interesting discoveries made in Greenland in recent
years, and shows that the previously entertained idea that during former
periods of maximum glaciation the land was entirely ice-covered is
incorrect.

The information now in hand concerning the Greenland ice sheet is
the result of combined observations of many explorers. Space will not
admit of an historical review of the slow progress that has been made in
gathering information of scientific value in the far north, but the student
who desires to follow up the subject will find the necessary references in



GLACIERS IN THE GREENLAND REGION. 135

the summaries of the geological results of northern exploration indicated
in the following footnote. 1

The rough ice met with on the borders of Greenland has been
described by many writers. South of about latitude 70 it presents the
characteristics of the lower extremities of alpine glaciers in less remote
regions. In the northern part of the continent, however, it ends in
exceptionally precipitous slopes. The tongue of ice reaching seaward
between bold uplands on the west coast near Disco island, in latitude 69
30', is a characteristic example of what may be seen at many other local-
ities on the wild Greenland coast. This protrusion of the island ice is
described by Lieutenant Peary as follows :

" Wherever the ice projects down a valley in a long tongue or stream,
the edges contract and shrink away from the warmer rocks on each side
having a deep canon between, usually occupied by a glacial stream. . . .
Higher up, along the unbroken portion of the dam [i.e. enclosing moun-
tains], where the rocks have a southern exposure or rise much above the
ice, there is apt to be a deep canon between the ice and the rocks ; the
ice face, sometimes 60 feet high, pure, pale green, and flinty. 2 In another
place the ice face may be so striated and discolored as to be a precise
counterpart of the rock opposite, looking as if torn from it by some con-
vulsion. The bottom of the canon is almost invariably occupied by
water. . . . Still farther up, at the very crest of the dam, the ice lies
smoothly against the rocks.

"As to the features of the interior beyond the coastline, the surface
of the ' ice blink ' near the margin is a succession of rounded hummocks,
steepest and highest on their landward sides, which are sometimes pre-
cipitous. Farther in these hummocks merge into long, flat swells, which
in turn decrease in height toward the interior, until at last a flat, gently
rising plain is reached, which doubtless becomes ultimately level."

The great Humboldt glacier, already referred to, presents another
example of the characteristic scenery of the Greenland coast, as is shown
by the following graphic description by Dr. Kane :

1 Dr. H. Rink, " Results of the Recent Danish Explorations in Greenland with Regard
to the Inland Ice (1878-1889)," in Edinburg Geol. Soc. Trans., vol. 5, 1888, pp. 286-293.

Dr. F. Nansen, "First Crossing of Greenland," vol. 1, pp. 450-510.
G. Frederick Wright, "Ice Age in North America," pp. 67-91.

Warren Upham, "The Ice Sheet of Greenland," in American Geologist, vol. 8, 1894,
pp. 145-152.

James Geikie, "The Great Ice Age," 3d ed., 1894, pp. 42-61.

T. C. Chamberlin, in the Geological Journal (Chicago) for 1894-1896.

2 American Geographical Society, Bulletin, vol. 19, 1887, p. 286.



136 GLACIERS OF NORTH AMERICA.

" The trend of this glacier is a few degrees to the west of north. We
followed its face eastward, edging in for the Greenland coast, about the
rocky archipelago which I have named after the Advance. From one of
these rugged islets, the nearest to the glacier which could be approached
with anything like safety, I could see another island larger and closer in
shore, already half covered by the encroaching face of the glacier, and
great masses of ice still detaching themselves and splintering as they fell
upon the portions which protruded. Repose was not the characteristic of
this seemingly solid mass ; every feature indicated activity, energy,
movement.

" The surface seemed to follow that of the adjacent country over which
it flowed. It was undulating about the horizon, but as it descended
toward the sea it represented a broken plain with a general inclination of
some nine degrees, still diminishing toward the foreground. Crevasses,
in the distance mere wrinkles, expanded as they came nearer, and were
crossed almost at right angles by long continuous lines of fracture parallel
with the face of the glacier.

" These lines, too, scarcely traceable in the far distance, widened as
they approached the sea, until they formed a gigantic stairway. It seemed
as though the ice had lost its support below and that the mass was let
down from above in a series of steps. Such an action, owing to the heat
derived from the soil, the excess of surface-drainage, and the constant
abrasion of the sea, must in reality take place. The indications of a great
propelling agency seemed to be just commencing at the time I was observ-
ing it. These split-off lines of ice were evidently in motion, pressed on
by those behind, but still widening their fissures, as if the impelling
action was more energetic near the water, till at last they floated away in
the form of icebergs. Long files of these detached masses could be traced
slowly sailing off into the distance, their separation marked by dark
parallel shadows broad and spacious avenues near the eye, but narrowed
in the perspective to mere lines. A more impressive illustration of the
forces of nature can hardly be conceived. . . .

" The frozen mass before me was similar in structure to the Alpine and
Norwegian ice growths. It would be foreign to the character of this book
to enter into the discussion which the remark suggests ; but it will be
seen by the sketch, imperfect as it is, that their face presented nearly all
the characteristic features of the Swiss Alps. The 'overflow,' as I have
called the viscous overlapping of the surface, was more clearly marked
than upon any Alpine glacier with which I am acquainted. When close



GLACIERS IN THE GREENLAND REGION. 137

to the island rocks and looking out upon the upper table of the glacier, I
was struck with the timely analogy of the batter-cake spreading itself
under the ladle of the housewife, the upper surface less affected by
friction, and rolling forward in consequence.

" The crevasses bore the mark of direct fracture and the more gradual
action of surface drainage. The extensive watershed between their con-
verging planes gave to the icy surface most of the hydrographic features
of a river system. The ice-born rivers which divided them were margined
occasionally with spires of discolored ice and generally lost themselves in
the central area of the glacier before reaching its foreground. Occasion-
ally, too, the face of the glacier was cut by vertical lines, which, as in the
Alpine growths, were evidently outlets for the surface drainage. Every-
thing was, of course, bound by solid ice when I looked at it ; but the
evidence of torrent-action was unequivocal, and Mr. Bonsall and Mr.
Morton, at their visit of the preceding year, found both cascades and
water tunnels in abundance.

" The height of this ice wall at the nearest point was about 300 feet,
measured from the water's edge ; and the unbroken right line of its
diminishing perspective showed that this might be regarded as its con-
stant measurement. It seemed, in fact, a great icy table-land abutting
with a clean precipice against the sea. This is, indeed, characteristic of
all those Arctic glaciers which issue from central reserviors, or mers de
glace, upon the fiords or bays, and is strikingly in contrast with the de-
pendent or hanging glaciers of the ravines, whose every line and furrow
and chasm seems to indicate the movement of descent and the mechanical
disturbances which have retarded it. ...

fr As the surface of the glacier receded to the south, its face seemed
broken with piles of earth and rock-stained rubbish, till far back in the
interior it was hidden from me by the slope of a hill. Still beyond this,
however, the white blink or glare of the sky above showed its continued
extension.

" It was more difficult to trace this outline to the northward on account
of the immense discharges at its base. The talus of its descent from the
interior, looking far off to the east, ranged from seven to fifteen degrees,
so broken by the crevasses, however, as to give the effect of an inclined
plane only in the distance. A few black knobs rose from the white snow
like islands from the sea. The general configuration of its surface showed
how it adapted itself to the inequalities of the basin-country beneath.
There was every modification of hill and valley, just as upon land."



138 GLACIERS OF NORTH AMERICA.

The margin of the inland ice on the east side of Greenland has been
explored, especially by Nansen, and found to have the same general char-
acteristics as on the west coast, excepting that the strip of mountainous
country intervening between the sea of ice in the interior and the sea of
water to the east is narrower, and the ascent steeper. Several large glaciers
are known on the east coast similar in character to the Humboldt glacier,
and the adjacent waters are crowded with icebergs and with floe ice.

The northern coast of Greenland, at least as far as Cape Washington,
the present limit of exploration, was found by Lockwood and Brainard to
be formed by bold rock headlands separated by deep valleys and wild,
desolate fiords. The mountains are snow-covered, but glaciers are not a
conspicuous feature of the stern landscape, and, so far as known, none of
them reach the sea. The character of the coast as seen from Cape
Britannia, lat. 82 45', is indicated in the following description by Lieu-
tenant Lockwood : 1

" Owing to the continued bad weather my view of the interior was
mainly confined to what I saw from the two elevations recorded ; and
owing to their comparative lowness, the range of mountain peaks, with
their universal covering of snow, merging and overlapping one another,
made it very difficult to distinguish the topography at all. The interior
land seemed very high and on this account the farthest that I could see
could not have been very many miles removed. I could see (from
Britannia and Lockwood islands) no glaciers that I could recognize as such,
though from the floe, while traveling, I saw a very large one and one or
two quite small. From my farthest I saw mountains to the east, perhaps
twenty or thirty miles distant, and a high mountainous country doubtless
exists along this coast for some distance to the south; the shore line of the
fiords invariably begin at the base of steep cliffs and mountains. No land
was seen to the north. There was a very noticeable abundance of snow
everywhere."

The above observations on the snowy covering of the north coast of
Greenland were made in May. Judging from the reports of Lieutenant
Peary, who found an abundance of flowers at the farthest point reached
during his overland journey, much of the land seen by Lockwood must be
bare of snow in late summer.

Far, to the north, as discovered by Lieutenant Peary during his first
famous journey over the inland ice, the fringe of mountains bordering the

1 "Report of the Proceedings of the U. S. Expedition to Lady Franklin Bay," vol. 1,
p. 188.



GLACIERS IN THE GREENLAND REGION. 139

coast of Greenland and intervening between the vast snow plateau of the
interior and the shore line, becomes broader, and the inland ice is limited
in that direction in about the same manner as on the better-known por-
tions of the coast to the southward. The termination of the inland ice
before reaching the northern border of the land is a significant fact, which,
taken in connection with the unglaciated condition of northern Alaska,
suggests that possibly the north end of Greenland was free of ice even
during the glacial period.

The combined observations of many explorers show that the great
reservoir of snow and ice covering central Greenland, and supplied solely
from the atmosphere, overflows in all directions through passes in the
bordering mountains so as to form separate ice tongues, but does not enter
the sea bodily, as one might say, on any considerable portion of its
boundary. In this respect the continental glacier of the northern hemi-
sphere differs from the similar ice body in Antarctic regions, which for a
large part of its periphery extends out into the sea, and forms continuous
ice cliffs several hundred miles long. Two phases in the existence of con-
tinental glaciers are thus illustrated. The one at the north is apparently
receding and contracting into boundaries, while the one at the south is yet
in its full vigor, and is possibly still increasing.

Thanks to the daring and zeal of a few explorers who have traversed
the interior of Greenland, we know what the surface of a continental
glacier is like, and are enabled to picture with considerable confidence the
character of large portions of North America, now thickly peopled, as it
existed during the height of the glacial period.

The first successful attempt to pass beyond the rugged borders of
Greenland and travel on the snow surface of the interior, was made by the
celebrated Swedish navigator, Baron Nordenskiold, in 1883. Leaving the
west coast a little to the south of Disco bay, he traveled inland for
eighteen days over a continuous snow-covered ice field which presented the
characteristic features of the neve of Alpine glaciers, and rose gradually
higher and higher the farther he proceeded. The region of nunataks was
passed and a bold advance made over the clear unbroken surface of the
inland ice which stretched away to the horizon as a boundless sea of un-
broken snow. About the only conspicuous details of the surface were
channels in which clear, swift streams coursed along between walls of ice.
These streams were short, however, as they soon plunged into crevasses or
moulins and disappeared to join the general subglacial drainage. The
murmur of waters far below the surface told of streams flowing in icy



140 GLACIERS OF NORTH AMERICA.

caverns beneath. We now know that these features pertain to the outer
border of the ice sheet, extending, it is true, some distance inland beyond
the fringe of nunataks, but are wanting over the greater part of the
central region.

At the end of his inland journey Nordenskiold reached a locality
about 73 miles from the coast and an elevation of 5000 feet. He then
sent his two Lap companions forward on sH, or Norwegian snow-shoes,
for a distance, it is estimated, of approximately 65 miles, or 138 miles from
the starting point on the coast. The elevation at the farthest point
reached is reported as being 5850 feet above the sea. To the eastward
the surface still continued to rise, showing that the summit of the ice sheet
was not gained. Nansen 1 has given reasons for concluding that the dis-
tance traversed by the Lapps after leaving the main party was over-
estimated, and that in reality the farthest point reached was but 11 8, miles
inland.

The explorations on the inland ice made by Nordenskiold decided once
for all that the previously entertained hypothesis in reference to the
presence of an area in the interior of Greenland free from ice and perhaps
inhabited is untenable.

In 1888, Lieut. R. E. Peary, who has since made three remarkable
journeys on the inland ice of northern Greenland, made a reconnoissance
in company with Christian Maigaara, a Danish officer in the Greenland
service, to the east of Disco bay, and some 75 or 100 miles north of the
route followed by Nordenskiold. During this reconnoissance Peary ad-
vanced about 100 miles from the coast and reached an elevation of 7525
feet on the unbroken surface of the inland ice.

Important as was the first venture that Peary made into the unex-
plored interior of Greenland, it has been far surpassed both by Nansen and
by Peary himself in subsequent years.

Dr. Fridtjof Nansen, the most intrepid of Arctic explorers, with four
companions, crossed Greenland from east to west in 1888, between lati-


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Online LibraryIsrael C. (Israel Cook) RussellGlaciers of North America; a reading lesson for students of geography and geology → online text (page 15 of 24)