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We have been elaborating a theory under which this ice had once a negative buoyancy due to the morainic material on top and in the lower layers of the ice mass, and had subsequently floated when the greater amount of this material had weathered out. Have arranged to go to C. Royds to-morrow.
A large proportion of the smaller lakes are dammed up by barriers of unstratified drift, having the exact character of the moraines of glaciers, and are termed by geologists "morainic," but some of them are true rock-basins, and would hold water even if all the loose drift now resting on their margins were removed.
We learn from M. de Mortillet that in the peat which has filled up one of the "morainic lakes" formed by the ancient glacier of the Ticino, M. Moro has discovered at Mercurago the piles of a lake-dwelling like those of Switzerland, together with various utensils and a canoe hollowed out of the trunk of a tree.
Since the disappearance of the ice these glacial flood plains have been dissected by the shrunken rivers of recent times and left on either side the valley in high terraces. Valley trains head in morainic plains, and their material grows finer down valley and coarser toward their sources. Their gradient is commonly greater than that of the present rivers.
The bands on this berg were particularly well defined; they were due to morainic action in the parent glacier. Later in the day the easterly wind increased to a gale. Fragments of floe drifted past at about two knots, and the pack to leeward began to break up fast.
Geikie, and others, that the abrading action of ice has formed some mountain tarns and many morainic lakes; but when it is a question of the origin of larger and deeper lakes, like those of Switzerland or the north of Italy, or inland fresh-water seas, like those of Canada, it will probably be found that ice has played a subordinate part in comparison with those movements by which changes of level in the earth's crust are gradually brought about.
May 15 was a great day. We made our hoosh at 7.30 a.m. Then we loaded up the boat and gave her a flying launch down the steep beach into the surf. Heavy rain had fallen in the night and a gusty north- westerly wind was now blowing, with misty showers. The 'James Caird' headed to the sea as if anxious to face the battle of the waves once more. We passed through the narrow mouth of the cove with the ugly rocks and waving kelp close on either side, turned to the east, and sailed merrily up the bay as the sun broke through the mists and made the tossing waters sparkle around us. We were a curious-looking party on that bright morning, but we were feeling happy. We even broke into song, and, but for our Robinson Crusoe appearance, a casual observer might have taken us for a picnic party sailing in a Norwegian fiord or one of the beautiful sounds of the west coast of New Zealand. The wind blew fresh and strong, and a small sea broke on the coast as we advanced. The surf was sufficient to have endangered the boat if we had attempted to land where the carcass of the sea-elephant was lying, so we decided to go on to the head of the bay without risking anything, particularly as we were likely to find sea-elephants on the upper beaches. The big creatures have a habit of seeking peaceful quarters protected from the waves. We had hopes, too, of finding penguins. Our expectation as far as the sea-elephants were concerned was not at fault. We heard the roar of the bulls as we neared the head of the bay, and soon afterwards saw the great unwieldy forms of the beasts lying on a shelving beach towards the bay-head. We rounded a high, glacier-worn bluff on the north side, and at 12.30 p.m. we ran the boat ashore on a low beach of sand and pebbles, with tussock growing above high-water mark. There were hundreds of sea-elephants lying about, and our anxieties with regard to food disappeared. Meat and blubber enough to feed our party for years was in sight. Our landing-place was about a mile and a half west of the north-east corner of the bay. Just east of us was a glacier-snout ending on the beach but giving a passage towards the head of the bay, except at high water or when a very heavy surf was running. A cold, drizzling rain had begun to fall, and we provided ourselves with shelter as quickly as possible. We hauled the 'James Caird' up above highwater mark and turned her over just to the lee or east side of the bluff. The spot was separated from the mountain-side by a low morainic bank, rising twenty or thirty feet above sea-level. Soon we had converted the boat into a very comfortable cabin
The oversteepened sides of the trough are graded by landslips, by talus slopes, and by alluvial cones. Morainic heaps of drift are dissected and carried away. Hanging valleys and the irregular bed of the trough are both worn down to grade by the streams which now occupy them.
He found that the ridge of the beach was formed by a glacial moraine, while accumulations of boulders, banked up in morainic ridges, concentric with one another and with the beach moraine, extended far out from the shore like partly sunken reefs.
A few feet in front of this wall is a ridge of loose materials, stones, pebbles, and boulders, repeating exactly the outline of the ice where it now stands; a few feet in advance of this, again, is another ridge precisely like it; still a few feet beyond, another; and so on, for four or five concentric zigzag crescent-shaped moraines, followed by two others more or less marked, till they fade into the larger morainic mass, upon which stands the belt of wood dividing the present glacier from the bay.
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