GEOLOGICAL SERIES

OF

FIELD MUSEUM OF NATURAL HISTORY

Volume VII Chicago, May 26, 1937 No. 1

THE GRINNELL ICE-CAP

By Sharat K. Roy

Curator of Geology

Results of the Rawson-MacMillan Subarctic Expedition of 1927-28

The Grinnell Ice-cap has not yet been fully explored, and con-
sequently its nature, behavior, and extent are only partially known.
The purpose of this paper is to publish such data as could be found
and make them available for those interested in glaciers and glacier
explorations.

I have been particularly fortunate in having known the members
of the various expeditions which have visited the ice-cap within the
last few years. I have secured their field notes or have discussed
the subject at length with them. My own visit to Frobisher Bay
has also aided me in understanding certain features of the ice-cap.

I wish to express here my sincere appreciation to Captain J. T.
Crowell, Jr., for permission to use his field notes and for critically
going over them with me; to Mr. Ralph E. Brooks for the photo-
graphs (figs. 2, 3, 6, 7, and 8) and for helpful information; to Mr.
Kennett Rawson for assistance rendered in the field; and. finally,
to Captain Donald B. MacMillan for many considerations shown
me during the expedition.

The Grinnell Ice-cap occupies the summit of the highland be-
tween Hudson Strait and Frobisher Bay, Baffin Land. Although
Sir Martin Frobisher discovered Frobisher Bay in 1576 and led two
more expeditions in the following summers into the same bay within
sight of the ice-cap, there is no reference to it in any of the literature
concerning his voyages. Apparently, he was not interested in gla-
ciers, or he believed the ice-cap to be a snow-covered area — a feature
common to arctic regions.

The first mention of the ice-cap appeared in 1865. In that year,
Captain Charles Francis Hall, in his "Arctic Researches and Life
among the Esquimaux," published the results of his explorations
about Frobisher Bay, then known as Frobisher Strait, in the years

No. 383

-Statural History^ttorrty --,

library

2 Field Museum of Natural History— Geology, Vol. VII

1860-62, and described the ice-cap, which he named Grinnell Glacier
after Henry Grinnell of New York. Captain Hall was an American
navigator, who afterwards became Commander of the United States
Polar Expedition ship, the Polaris.

Unfortunately, Hall's description is much too indefinite and is
unsatisfactory from a geological point of view. He placed too
great faith in the hearsay information of his Eskimo companions.
As a result, many of his statements, derived from that source, can only
be accepted as indirect evidence. Nevertheless, his description con-
tains many useful data which may be of interest, particularly to
those who may visit and study the ice-cap1 at any future time.

Since Hall's Journal is not readily accessible and since his descrip-
tion of the ice-cap is widely scattered, I have deemed it advisable to
quote here such portions as might be of interest and have immediate
bearing on the present subject.

August 21, 1860 [p. 118]. — -The land on the opposite side of the "Straits"2 was
clear before me, though at a distance of some forty miles, and it appeared as if a
long line of ice or snow topped a considerable portion of it. . . . But not till some
months afterward, when exploring up the "Straits," did I have positive proof that
what I now saw was really an enormous and magnificent glacier, which, when I
visited it, I called after the name of Henry Grinnell.

April 25, 1861 [pp. 262-263]. — As we traveled forward [from near Nouyarn
Island, Lat. 62° 55' N., Long. 65° 52' W.] the mountains of Kingaite [an Eskimo name,
same as Meta Incognita of Sir Martin Frobisher] loomed up in magnificent grandeur.
... It seemed as if a huge ice ridge ran along parallel with the coast, uniting
mountain with mountain and peak with peak. Seeing how intent I was upon this,
Kokerjabin [an Eskimo woman companion] readily answered my inquiry as to what
it really was. In reply, she said that it was solid ice, and never had she known it
to change its appearance, either in summer or fall.

May 1st, 1862 [pp. 516-521]. — I started from this encampment [ninth encamp-
ment, Lat. 62° 51' N., Long. 66° 40' W., due east of Gabriel Island] on a trip to

Precautionary measures should be taken before a trip to the ice-cap is
attempted. Frobisher Bay has never been officially charted. The only chart
available is the one accompanying Hall's "Arctic Researches and Life among the
Esquimaux." This is, however, an outline geographical map and, therefore, not
of great value to navigators. Furthermore, the map contains many inaccuracies
due to the fact that Hall made the greater part of his observations from a distance,
and that, too, in the winter, when the snow covered both ice and land. The bay
contains numerous shoals, low islands, and hidden jutting rocks, so that anyone
not previously warned of the dangers is apt to have his boat on the rocks when his
journey has scarcely begun. The tides in the bay, as observed in 1927, rise as high
as forty-eight feet and when setting in different directions among islands create
currents of great velocity and often give rise to dangerous whirlpools. The region
is also notoriously stormy and for the most part obscured by fog. The Eskimos,
who are thoroughly familiar with these conditions, are of inestimable service and
should be procured as guides.

2 Hall reached the headwaters of Frobisher Bay in the summer of 1861. Until
then it was known as the "Straits" — an open arm of Davis Strait.

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The Grinnell Ice-cap 3

Kingaite coast. . . . We started, at 7:40 A.M., for the point [President's Seat, the
most conspicuous mountain on the coast of Frobisher Bay, Lat. 62° 39' N., Long.
66° 40' W.] I had selected . . . where an ascent could probably be made of the
glacier which I had seen on my voyage up the bay the previous fall [spring].

My course across the bay to Kingaite coast was S. 4° E., true. The num-
ber of dogskin the team was ten, but, as they were in poor condition, we made
but three and a half to four and a half miles per hour. ... A few minutes before noon
we drew into a small bay that extended on toward the point I sought to reach. . . .
As the dogs turned up the narrow bay leading to the point of land we were
making, I was delighted to see the face of an abutting glacier, which fully proved
the truth of my anticipations that there were iceberg discharges on Kingaite side.
At noon our progress was arrested by the glacier, which seemed to smile a defiance.
. . . Here, by this crystal wall, I stood . . . beholding its beauty and grandeur . . . ,
after which we were prepared for an attempt to scale the ice-mountain. This could
be done only by ascending one of the rock ridges flanking the abutting arm of the
glacier, and thence striking up its steep side.

For the first quarter of a mile it was very abrupt, and difficult to climb. The
most laborious and dangerous part of the ascent was accomplished by following
the footsteps of a polar bear. . . . After first quarter of a mile the inclination of the
glacier was gradual, then for a quarter of a mile farther it became greater, but it
did not so continue. Each side of this arm of the glacier was walled in by moun-
tains, the east side by the group I called the President's Seat.

On making two miles, S. 16° E., true, we arrived where the glacier opens to
a sea of ice. At this time and point the glacier was covered with snow, with a
cropping out here and there of the clear crystal blue ice, giving relief to the view
of an apparently illimitable sea of white around. My Innuit [Eskimo] companion,
being well experienced in all the coast from Karmowong, a place on the north side
of Hudson's Straits, to Resolution Island, and all about Frobisher Bay, said that
this great glacier extended far, far below where we then were, and also continued
on northwest a great way, reaching over [to southeast] also nearly to Hudson's
Straits. From the information I had previously gained, and the data furnished
me by my Innuit companion, I estimated the Grinnell Glacier to be fully 100 miles
long. At various points on the north side of Frobisher Bay, between Bear Sound
[Lat. 62° 31' N., Long. 64° 50' W., named by Frobisher in 1577 after James Bear,
master of the Michael, one of the expedition ships of Frobisher] and the Countess
of Warwick's Sound, I made observations by sextant, by which I determined that
over fifty miles of the glacier recedes from the coast, and is lost to view by the
Everett chain [Lat. 62° 40' N., Long. 67° W.] of mountains; and as Sharkey [a male
Eskimo companion] said, "the ou-u-e-too [ice that never melts] extends on wes-
se-too-ad-too [far, very far off]." He added that there were places along the coast
below what I called the President's Seat where this great glacier discharges itself
into the sea, some of it large icebergs.

From the sea of ice down to the point where abutting glacier arrested my
advance with sledge and dogs, the ice-river or arm of the glacier was quite uniform
in its rounding up, presenting the appearance . . . though in a frozen state ... of a
mighty rushing torrent. The height of the discharging face of the glacier was 100
feet above the sea.

In 1897, thirty-five years after Hall's exploration of Frobisher
Bay, Russell W. Porter, accompanied by a party of seven men,

1 1

6 Field Museum of Natural History — Geology, Vol. VII

entered Frobisher Bay on August 11. He ascended the Grinnell
Ice-cap on September 5 by way of a tongue-like outlet descending
into Watt's Bay, Lat. 62° 38' N. This tongue was named Boas
Glacier by Porter after the distinguished anthropologist, Dr. Franz
Boas, of Columbia University. Porter's brief description of the ice-
cap is as follows:

Thursday evening, Sept. 4th, the boats entered Watt's Bay (14th encampment),
and the tents were pitched on its northern shore. . . . Across the bay, two miles to
the southwest, was the blue wall of a glacier (Boas Glacier), hemmed in on either
side by high mountains. On the horizon, back of it, a luminous glare from the
ice-cap lit up the fog and mist which was shutting down over the landscape.

The next day, although fog and occasional rain made climbing disagreeable,
we ascended the glacier. One mile to the right of its face a beautiful waterfall
emptied into the bay. From an elevation of 300 feet above high water this glacial
stream slid over the smooth rock in a convex elliptical curve, which at the water's
edge was nearly vertical.

The face of the Boas Glacier is approximately 150 feet high and has a
frontage of some 100 yards. The glacier was not discharging to any noticeable
extent, there being no bergs in Watt's Bay.

In the center of the ice stream, and perhaps half a mile from its face, the writer
set up a signal pole of bamboo, marking the spot additionally with a pile of rocks.
Then cairns were erected on the shore in line with the pole, and sketches of the sur-
rounding locality made for the purpose of identifying the spot in winter.1

The Boas Glacier is an easy one to travel on. It has an angle of descent of 15°
with the horizon, and on its southern side one can walk directly to the ice-cap above.
It can be crossed at almost any point. Its surface is clean and hard, carrying but
little detritus, and in September was melting and furrowed by many streams of
water. The so-called "pot holes," found in numbers on the Greenland glaciers,
were conspicuous by their almost total absence.

At a distance of two miles from the face of the glacier the consistency of its
ice changes to that of snow, and half a mile farther on, the ice has entirely dis-
appeared as well as the crevasses. The horizon to the west was obscured by fog,
but the appearance of the ice-cap at this place was that of rolling plains of snow
through which a single nunatak forced itself.

The writer, accompanied by Mr. Shaw, reached this "island of white sea" after
floundering through wet snow knee-deep, and succeeded in reaching its summit,
where a cairn was built and a record deposited. It had an elevation above the bay
(by aneroid) of 2,380 feet.

In the summer of 1927, while a member of the Rawson-MacMil-
lan Subarctic Expedition to Labrador and Baffin Land, I made
several attempts to study the nature and extent of the Grinnell Ice-
cap but I was handicapped by foggy weather and other menaces to
navigation. The difficulties encountered and the limited results

1 Porter intended to revisit the glacier the next summer (1898) to ascertain
its rate of flow, but this he was unable to do.

8 Field Museum of Natural History— Geology, Vol. VII

achieved may be gathered from the following account, summarized
from my field notes:

We crossed Hudson Strait, passed around the east side of Resolu-
tion Island, and headed westward, entering Frobisher Bay on the
evening of August 9. An impenetrable fog and a turbulent sea pre-
vented us from hugging the coast and we did not see the south-
eastern extent of the ice-cap.

Our first anchorage was in an unnamed bay (Lat. 62° 13' N., Long.
66° W.), about nine miles southeast of Jackman's Sound. Here
we anchored two days, during which time I made four attempts to
see the ice-cap, going far inland and ascending 1,830 feet (aneroid),
but the fog never once lifted and it was impossible to see anything
beyond a few feet. On the morning of August 12 the weather cleared
a little, but as our working days were numbered and much recon-
noitering was ahead of us, we heaved anchor and sailed northwest-
ward, keeping as close to the shore as safety would permit. Within
an hour (we were running about 8 nautical miles an hour), for the
first time we saw the glistening white surface of the ice-cap and
several tongues (fig. 2) at intervals of one-half to two miles flowing
in the valleys of the high, rocky coast of the bay. None of these
tongues, however, seemed high or thick. Apparently, there was
occasional calving, as evidenced by small icebergs (fig. 3) near-by
or at the head of some of the inlets. We tried to make shore, hoping
that it might be possible to reach the ice-cap by way of one of the
tongues, but the sea was still very heavy. High waves dashed against
the bold cliff; we could not land. We continued our journey and
hoped that the sea would moderate, but before long we lost sight of
the ice-cap. At dusk we entered Griffin Bay, a deep fiord, evidently
the result of glacial excavation and coastal sinking. So deep was the
fiord that we could not find anchorage with a hundred-fathom chain
within fifty feet from the shore. Finally we moored with quarter
lines to a cliff.

On the following morning (August 14), Kennett Rawson and I
worked our way inland for a distance of four miles. In the course
of our walk, we saw evidences of former glaciation — dammed-in lakes
(fig. 4), ground moraines, massive striated boulders, well-developed
cirques (fig. 5), U-shaped valleys, aretes, horns, and practically
every major sculpture one might expect to find in a region which
once supported large valley glaciers. By now, it was evident to us
that the longitudinal direction of the ice-cap was not wholly parallel to
the coast as we had believed it to be when on our way to Griffin Bay,

FlG. 4. A glacial lake near the head of Griffin Bay.

10 Field Museum of Natural History — Geology, Vol. VII

but must be at an angle. To check our inference, we ascended a
high hill (2,420 feet, aneroid) to our right. As we reached the summit
facing southeast, the ice-cap appeared in the distance like a white
Sahara, lying, as we had expected, in southeast-northwest direction.
The southeast border was near and more or less parallel to the coast;
the northwest border was many miles farther inland. The advance of
the ice-cap on the southeast side seemed checked by the bold walls
of an incredibly barren coast except at a few flanks through which
it was finding its sinuous way to the sea. We could not estimate the
distance between us and the ice-cap but it could not have been less
than four miles on the southeast side, perhaps more. We had no
way of judging the distance to the northwest side. Snow-capped
hills rose above hills, beyond which lay a white ridge of which we had
but a few glimpses through the rifts in the fog.

According to Hall's chart, the ice-cap was not only supposed to
exist where we were but also to extend at least seventeen miles north-
east of us. So far as we could see, it does extend northward but its
extent is to the northwest, not northeast. Hall, as stated before
(footnote 1, p. 2), made his observations during winter when snow
covered both ice and land, and this might well have been the source
of his error.

In 1929 Captain Donald B. MacMillan, Ralph E. Brooks, Ken-
nett Rawson, and Frank Henderson ascended the ice-cap from a
tongue reaching out to York Sound. Unfortunately, no notes were
taken of the trip, and the details of their exploration are, therefore,
not available. I was, however, informed verbally by Mr. Brooks
that he had traveled a considerable distance in various directions
over the ice-cap and that both he and Captain MacMillan had
independently observed that it was not continuous but was divided
by a non-glaciated area some distance south of York Sound. They
also erected a pole on the ice front by which to check the rate of the
advance of the ice-cap, but two years later when Mr. Brooks again
visited the place he was unable to locate the mark.

In August, 1931, Captain J. T. Crowell, Jr., and Mr. Brooks, the
radio operator of the Bowdoin, ascended the Grinnell Ice-cap and
traveled the greater part of a day over it. The record of their travel
is the most illuminating of any information as yet known of this
ice-cap. It gives an excellent picture of the conditions one would
meet when setting out to explore the ice-cap. With Captain Crowell's
permission, I am quoting here the following extracts from his
log book:

Fig. 5. A well-developed cirque. Northwest coast of Frobisher Bay.

II

12 Field Museum of Natural History— Geology, Vol. VII

Schr. Bowdoin, Frobisher Bay: August 5, 1931. —We entered York Sound, Lat.
62° 34' N., Long. 66° 35' W., on the afternoon of August 5, 1931, and hoped for clear
weather so that we could photograph the glacier. "One tongue of it enters this sound
and slopes off gradually so as to afford access to the surface of the glacier. We could
not take pictures of the ice because of the fog but Ralph Brooks [the radio operator]
and I decided to ascend without waiting for the weather to clear. Ralph was on
this very ice tongue two years ago with MacMillan, Frank Henderson, and Ken-
nett Rawson, when the Boivdoin was in here before.

At about nine in the morning we got on the glacier [fig. 6] on the southeast
corner and working to the right to avoid crevasses as much as possible where the
glacier turns to the southeast we worked up. When we were on top of the first
big rise, the fog began to shut in thicker and only at intervals could we see the very
high land on each side. Shortly after going around the bend which shuts out the
view of the bay we encountered crevasses, but we worked to the left again and were
soon clear of the worst of them. Brooks said that the surface of the glacier was
much more easily traversed than it had been two years ago. That was about
August 22 and most of the snow had gone from the top of the ice, making it very
glaring and slippery; also there was much more water running on the top than now.
The glacier turns again to the southward and becomes steeper. Here we stopped
and lashed the crampons on our feet. Proceeding, we caught glimpses of tre-
mendous ice-falls on the left coming down over a sheer cliff that must be a thousand
feet above the surface of the glacier. After passing this we encountered more snow
and we wandered in the fog, always ascending until we could see the high land on
the right side of the ice. Here also were ice-falls but much less in magnitude than
the others, seen on the left.

The snow was now deeper and the slope more steep; we were forced to zigzag
to find ice bridges on which to cross the crevasses. Looking down over the edge
we could see no bottom, and chunks of ice thrown in would rattle on down, the
sound growing fainter and fainter. We could not hear them striking bottom. The
crevasses varied in width from a few inches to several hundred yards.

After lunch we proceeded on our way up. There was not much water on this
part of the glacier, probably because it drained off into the many crevasses and did
not accumulate into streams as it did on other parts of the ice. We now judged it
to be about noon, and we began to get into better going and among fewer crevasses.
Fog was still with us and we kept expressing the hope that it would clear so that
Brooks could get pictures and we could get the lay of the land. Gradually we got
into smoother ice. We could hear a stream of water running on our left and ahead,
and we made our way towards the sound. The ice now became quite a bit steeper
and, as we proceeded, steeper still. We found the stream which was running very
rapidly in a bed about a foot deep and about four feet across, which it had worn in
the ice. There were no crevasses in this area. The ice had a very steep slope now
and we surmised that we must be above some ice-falls similar to those seen from
the lower glacier. We began to fear that we might get too close to the edge in the
fog and be in danger of slipping off, as the ice was smoother and covered with
running water; so we began to work eastward at right angles to the slope. Soon we
saw land on our left and below us slightly. We made for this and climbed out on it.
While Ralph was wringing some of the ice water out of his socks I worked over to
the other edge of the rock and peered down through the fog. There on my left was
the ice-fall [fig. 7] which passes on the west or southwest side of this nunatak.

13

14 Field Museum of Natural History — Geology, Vol. VII

Tremendous masses of ice, like icebergs, were hanging to the side of that sheer cliff,
which extended down beyond my vision. I could not see the glacier. We had no
barometer with us and could not judge the height, but must be very high, as I
felt very dizzy and slightly nauseated. Another ice-fall extended down on the other
side of our nunatak and also disappeared abruptly over the cliff and was lost in
the fog.

Here we wrote our record, signed it, enclosed it in the National Geographic
Society brass cylinder and placed it in a rock cairn on a high place in the rock
[fig. 8]. We also built two smaller cairns about ten feet from the edge of the ice
(on the rock) and mentioned them in our record, so that later investigators might
get some idea as to whether or not the ice is diminishing or increasing at this point.

After a rest of a few minutes we lashed on our crampons again and began our
return, as the fog was getting thicker and it began to look like bad weather. We
set out on the steep slope, being careful to keep away from the edge of the ice-falls
and headed for where we thought we would pick up the largest of the water streams
which we had seen. We found this and followed it down until we picked up our
footprints. These we followed carefully so as to keep clear of the treacherous snow
bridges over the crevasses, knowing that we were fairly safe in retracing our
upward course. At times we lost the trail owing to bad light and the faintness of
the crampon marks on hard ice, but we did not proceed until we picked them up
again. We did leave the trail to look at and photograph some very wide and deep
crevasses which must be near the ice-falls, although we could not see because of fog.
But we followed the tracks down across the bad crevasses and into a region where
there was deeper snow. This did not look good to us on the way up as we thought
some of it covered crevasses. We were right. I was walking along, with Ralph
about twenty-five feet in the rear (we were made fast to each other with about
thirty feet of twelve thread manila), when my right foot broke through the crust
and I fell forward. Sparks held taut on the line and braced himself, but the snow
held the weight of my body, and I crawled out on to firmer footing. I had time,
however, to look down that hole where my foot had broken through. As far down
as I could see there was nothing but blue space. A few minutes later Ralph broke
through with one foot, but he quickly stepped backward.

We continued to descend and in a half hour or so a break in the fog gave us a
glimpse of the lower part of the ice-falls. We now realized that we had proceeded
too far to the southeast side of the glacier. We were in another crevassed area
with much running water. Many of the streams rushed along in deep-worn ice
beds and suddenly plunged out of sight down a seemingly bottomless crevasse.
The hollow rumble of their descent came back to us. We retraced our steps for a
Way and found better going for a while, but at last were forced to work out to the
right to the very edge of the glacier and work along amongst the rocks and debris
of the edge of the lateral moraine. Even in there amongst the rocks there were
deep crevasses, as the rocks are only a superficial layer on top of very thick ice.

Gradually, we worked out onto better going and as we turned around the bend
we could see the vessel far down in the bay. It looked very small compared to the
ice and the huge cliffs. As we got down toward the shore edge of the ice tongue we
saw some one coming for us in the gig and soon after we met Simeon on the shore,
climbed into the boat and were soon aboard. It was about 5 P.M.

Friday, August 7, 1931. — The weather was still foggy so that no good pictures
could be taken of the glacier. Brooks and I climbed the old glacial trough, which is

Fig. 7. An ieo-fall. Grinnell Ice-cap flowing over a clilf.

15

16 Field Museum of Natural History— Geology, Vol. VII

on this bay [York Sound] but south of the glacier. There is a steep glacial tongue
coming part way down this old trough. We climbed about seven hundred feet and
came upon a small lake, as we had expected — a very deep basin with sheer walls
rising high. The water from the ice tongue, which is far above but in sight, plunges
down the bare rock for several hundred feet into this beautiful body of water. Last
year's ice had not wholly melted away yet so that pans of clear white ice were
floating on its glossy surface, and the snow banks still adhering to the cliffs were
reflected in the lake. It is of course too high to be seen from the ship in the bay.
We named this body of water Lake Alice, after Mrs. Crowell. We collected fossil-
bearing1 stones here and I made a collection of other rocks on the mountain. There
are many varieties of lichens and mosses near the lake and on the way up we saw
two arctic poppies; also other flowers and the purple flower which we see so often
now but whose name I do not know. Many signs of lemmings at one mossy place.

SUMMARY

The Grinnell Glacier occupies the summit of the highland between
Hudson Strait and Frobisher Bay, Baffin Land. It belongs to the
ice-cap class, having characteristics intermediate between those of
mountain and continental glaciers. Its southern portion lies more
or less parallel to the west coast of Frobisher Bay, which, except for a
few cuts and valleys, forms an effective barrier and prevents the
advancing ice from descending into the sea. The longitudinal
(southeast-northwest) dimension of the ice-cap is about eighty
miles. Probably the ice-cap is not continuous2 but is separated by a
non-glaciated area some distance south of Lat. 62° 30' N. The extent
of the ice-cap inland into the interior is not known, nor is its thickness
known. Along the front borders of its southeast portion, it sends out
several tongue-like outlets which, following a sinuous course, reach
out to sea. Calving is taking place at long intervals but the resulting
icebergs are of small size. Large icebergs (fig. 9) that are seen in and
about Frobisher Bay have evidently had their origin in the Greenland
ice-sheet.

The presence of many crevasses, which range from a few inches to
several hundred yards in width, indicates that the rock pedestal sup-
porting the ice-cap has numerous inequalities. So far as has been
observed, only a single peak projects above the ice-cap. This nunatak
can be more easily reached from a tongue descending into Watt's
Bay than from elsewhere.

It is doubtful if the ice-cap ever extended much farther to the
northeast than its present limit, for although the northeastern area

1 1 have not seen these fossils but I believe they are of Ordovician age, brought
down by the glacier from Silliman's Fossil Mount at the head of Frobisher Bay.

2 As observed by Mr. Brooks and communicated verbally to me. Mr. Brooks'
observation has been substantiated by Captain MacMillan.

Fig. 8. A rock cairn containing record of travel of Captain J. T. Crowell, Jr. (standing) an<
Ralph E. Brooks.

17

1

IggJ ,-g« 1

:B 1

Fig. 9. Icebergs in the vicinity of Frobisher Bay. These were discharged by the (.Greenland
ice-sheet and drifted southward.

18

The Grinnell Ice-cap 19

was glaciated it has none of the smooth and rounded features char-
acteristic of a terrain overtopped by an ice-sheet. On the contrary,
the landscape is extremely rugged, consisting of well-formed cirques,
U-shaped valleys, serrated ridges, etc., all of which indicate that the
region supported numerous independent mountain glaciers rather
than an ice-sheet. The disappearance of these mountain glaciers and
the existence of an ice-cap near-by may be due to decrease in atmos-
pheric moisture in the northeast area and to its lower altitude. The
Grinnell Ice-cap for the most part is surrounded on three sides by
large bodies of water, namely, Hudson Strait, Davis Strait, and
Frobisher Bay, and thus receives a much more plentiful supply of
moisture than the northeast area, which has only the water of Fro-
bisher Bay as its immediate source of nourishment. Furthermore,
the Grinnell Ice-cap is of sufficient size to develop a local descending
and centrifugally directed surface air current for at least part of
the year.

The best time of the year to travel over the ice-cap is late spring,
before the snows have begun softening or melting. The winter
snows are then well impacted and all the dangerous crevasses and
water holes are filled. Normally, however, it would be impossible to
enter Frobisher Bay at that time, for the sea is seldom, if ever, clear
of ice before the middle of July. The alternative is to winter there,
which seems to be the only way by which one can take advantage of
the best time of the year to explore the ice-cap.

UNIVERSITY OP ILLINOIS-URBANA

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