Crossing the glacial river above the upper archway, I reached the mountain side and began to ascend. The task was far more difficult than anticipated. The bushes, principally of alder and currant, grew dense and extended their branches down the steep slope in such a manner that at times it was utterly impossible to force a way through them. Much of the way I crawled on hands and knees up the steep watercourse beneath the dense tangle of vegetation overhanging from either bank and interlacing in the center. On nearing the top I was so fortunate as to strike a bear trail, along which the animal had forced his way through the bushes, making an opening like a tunnel. Through this I ascended to the top of the slope, coming out in a wild amphitheatre in the side of the mountain. The bottom of the amphitheatre was exceedingly rough, owing to confused moraine-heaps, and held a number of small lakes. On account of its elevation, it was not densely covered with bushes, and no trees were in sight except along its southern margin. About its northern border ran a broad terrace, marking the height of the great glacier which formerly occupied the site of Yakutat bay. The terrace formed a convenient pathway leading westward to a sharp ridge running out from the mountains and connecting with an outstanding butte, which promised to afford an unobstructed view to the westward.
Pressing on, I found that the terrace on which I was traveling at length became a free ridge, some three hundred feet high, with steep slopes on either side, like a huge railroad embankment. This ridge swept across the valley in a graceful curve, and shut off a portion of the western part of the amphitheatre from the general drainage. In the portion thus isolated there was a lake without an outlet, still frozen. The snow banks bordering the frozen lake were traced in every direction by the trails of bears. Continuing my tramp, I crossed broad snow-fields, climbed the ridge to the westward, and obtained a far-reaching, unobstructed view of the surrounding country. The elevation reached was only about 1,500 feet above sea-level, but was above the timber line. The mountain slopes toward the north were bare of vegetation and generally covered with snow.
The first object to claim attention was the huge pyramid forming the summit of Mount St. Elias, which stood out clear and sharp against the northwestern sky. Although thirty-six miles distant, it dominated all other peaks in view and rose far abovethe rugged crests of nearer ranges, many of which would have been counted magnificent mountains in a less rugged land. This was the first view of the great peak obtained by any of our party. Not a cloud obscured the defination of the mountain; and the wonderful transparency of the atmosphere, after so many days of mist and rain, was something seldom if ever equalled in less humid lands.
Much nearer than St. Elias, and a little west of north of my station, rose Mount Cook, one of the most beautiful peaks in the region. Its summit, unlike the isolated pyramid in which St. Elias terminates, is formed of three white domes, with here and there subordinate pinnacles of pure white, shooting up from the snow-fields like great crystals. On the southern side of Mount Cook there are several rugged and angular ridges, which sweep away for many miles and project like headlands into the sea of ice, known as the Malaspina glacier, bordering the ocean toward the southwest. Between the main ridges there are huge trunk glaciers, each contributing its flood of ice to the great glacier below; and each secondary valley and each amphitheatre among the peaks, no matter how small, has its individual glacier, and the majority of these are tributary to the larger ice-streams. All the mountains in sight exceeding 2,000 feet in elevation were white with snow, except the sharpest ridges and boldest precipices. The attention of the geologist is attracted by the fact that all the foot-hills of Mount Cook are composed of gray sandstone and black shale; and he also observes that the angular mountain crest so sharply drawn against the sky furnishes abundant evidence that the mountains were never subjected to the abrasion of a continuous ice-sheet.
As I stood on the steep-sloped ridge, the Atrevida and Lucia glaciers, their surfaces covered from side to side with angular masses of sandstone and shale, lay at my feet; while farther up the valley the débris on the surface of the ice disappeared, and all above was a winter landscape. The brown, desolate débris-fields on the glacier at my feet extended far southward, and covered the expanded ice-foot in which the glacier terminates. Most curious of all was the fact that the moraines on the lower border of the glacier were concealed from view by a dense covering of vegetation, and in places were clothed with forests of spruce trees.
To the southward, beyond the end of the Lucia glacier, and separated from it by a torrent-swept bowlder-bed, lay a vastplateau of ice which stretched toward the south and west farther than the eye could reach. This is the Malaspina glacier, shown on plate 8. Its borders, like the expanded extremity of the Lucia glacier, are covered with débris, on the outer margins of which dense vegetation has taken root. All the central portion of the ice-sheet is clear of moraines, and shone in the sunlight like a vast snow-field. The heights formerly reached by the nearer glaciers were plainly marked along the mountain sides by well-defined terraces, sloping with the present drainage. When the Lucia glacier was at its flood the ridge on which I stood was only 200 or 300 feet above its surface; now it approaches 1,000 feet.
Turning toward the southeast, I could look down upon the waters of Yakutat bay, with its thousands of floating icebergs, and could distinguish the white breakers as they rolled in on Ocean cape. Beyond Yakutat stretches a forest-covered plateau between the mountains and the sea, and the eye could range far over the mountains bordering this plateau on the northeast. In the distance, fully a hundred miles away, stood Mount Fairweather, its position rendered conspicuous by a bank of shining clouds floating serenely above its cold summit.
The mountains directly east of Yakutat bay rise to a general height of about 8,000 feet, but are without especially prominent peaks. In a general way they form a rugged plateau, which has been dissected in various channels to depth of 2,000 or 3,000 feet. Nearly all of the plateau, including mountains and valleys, is covered with snow-fields and glaciers; but none of the ice-streams, so far as can be seen from a distance, descend below an elevation of about 4,000 or 5,000 feet. This region is as yet untraversed; and when the explorer enters it, it is quite possible that deep drainage lines will be found through which glaciers may descend nearly or quite to sea-level.
After drinking in the effect of the magnificent landscape and endeavoring to impress every detail in the rugged topography upon my memory, and having finished writing my notes, it was time to return; for the sun was already declining toward the west. Wishing to see more of the wonderful land about me, I concluded to descend the western slope of the ridge upon which I stood, and to return to camp by following a stream which issues from the Atrevida glacier directly below my station and empties into Yakutat bay a mile or two south of our third camp.
The quickest and easiest way down was to slide on the snow. Using my alpenstock as a brake, I descended swiftly several hundred feet without difficulty, the dogs bounding along beside me, when on looking up I was startled to see two huge brown bears on the same snow surface, a little to the left and not more than a hundred and fifty yards away. Had my slide been continued a few seconds more I should have been in exceedingly unwelcome company. I was unarmed, and entirely unprepared for a fight with two of the most savage animals found in this country. The bears had long yellowish-brown hair, and were of the size and character of the "grizzly," with which they are thought by hunters, if not by naturalists, to be specifically identical. They were not at all disturbed by my presence, and in spite of my shouts, which I thought would make them travel off, one of them came leisurely toward me. His strides over the snow revealed a strength and activity commanding admiration despite the decidedly uncomfortable feeling awakened by his proximity and evident curiosity. Later in the season I measured the tracks of an animal of the same species, made while walking over a soft, level surface, and found each impression to measure 9 by 17 inches, and the stride to reach 64 inches. So far as I have been able to learn, this is the largest bear track that has been reported. Realizing my danger, I continued my snow slide, but in a different direction and with accelerated speed. The upper limit of the dense thicket clothing the slope of the mountain was soon reached, and my unwelcome companions were lost to sight.
Following the bed of a torrent fed by the snow-fields above, I soon came to the creek chosen for my route back to camp; the waters, brown and turbid with sediment, welled out of a cavern at the foot of an ice precipice 200 feet high, and formed a roaring stream too deep and too swift for fording. The roaring of the brown waters and the startling noises made by stones rattling down the ice-cliff, together with the dark shadows of the deep gorge, walled in by a steep mountain slope on one side and a glacier on the other, made the route seem uncanny. On the sands filling the spaces between the bowlders there were many fresh bear tracks, which at least suggested that the belated traveler should be careful in his movements.
This locality was afterward occupied as a camping place, and is shown in the picture forming plate 10. The dark-colored ice,mixed with stones and earth, might easily be mistaken for stratified rock; but the dirt discoloring the ice is almost entirely superficial. The crest of the cliff is formed of débris, and is the edge of the sheet of stones and earth covering the general surface of the glacier. Owing to the constant melting, stones and bowlders are continually loosened to rattle down the steep slope and plunge into the water beneath.
I followed down the bank of the stream, by springing from bowlder to bowlder, for about a mile, and then came to a steep bluff, the western side of which was swept by the roaring flood. The banks above were clothed with spruce trees and dense underbrush; but, there being no alternative, I entered the forest and slowly worked my way in the direction of camp. To traverse the unbroken forests of southern Alaska is always difficult, even when one is fresh; and, weary as I was with many hours of laborious climbing, my progress was slow indeed. One of the principal obstacles encountered in threading these Arctic jungles is the plant known as the "Devil's club" (Panax horridum), which grows to a height of ten or fifteen feet, and has broad, palmate leaves that are especially conspicuous in autumn, owing to their bright yellow color. The stems of this plant run on the earth for several feet and then curve upward. Every portion of its surface, even to the ribs of the leaves, is thickly set with spines, which inflict painful wounds, and, breaking off in the flesh, cause festering sores. In forcing a way through the brush one frequently treads on the prostrate portion of these thorny plants, and not infrequently is made aware of the fact by a blow on the head or in the face from the over-arching stems.
I struggled on through the tangled vegetation until the sun went down and the woods became dark and somber. Thick moss, into which the foot sank as in a bed of sponge, covered the ground everywhere to the depth of two or three feet; each fallen trunk was a rounded mound of green and brown, decked with graceful equiseta and ferns, or brilliant with flowers, but most treacherous and annoying to the belated traveler. In the gloom of the dim-lit woods, the trees, bearded with moss, assumed strange, fantastic shapes, which every unfamiliar sound seemed to start into life; while the numerous trails made by the bears in forcing their way through the thick tangle were positive evidence that not all the inhabitants of the forest were creatures of the imagination. My faithful companions, "Bud" and"Tweed" showed signs of weariness, and offered no objection when I started a fire and expressed my intention of spending the night beneath the wide-spreading branches of a moss-covered evergreen. Having a few pieces of bread in my pocket, I shared them with the dogs, and stretching myself on a luxuriant bank of lichens tried to sleep, only to find the mosquitoes so energetic that there was no hope of passing the night in comfort.
After resting I felt refreshed, and concluded to press on through the gathering darkness, and after another hour of hard work I came out of the forest and upon a field of torrent-swept bowlders, deposited by the stream which I had left farther up. I was surprised to find that the twilight was not so far spent as I had fancied. The way ahead being free of vegetation, I hastened on, and after traveling about two miles was rejoiced by the sight of a camp-fire blazing in the distance. The warm fire and a hearty supper soon made me forget the fatigues of the day.
This, my first day's exploration, must stand as an example of many similar days spent on the hills and in the forests northwest of Yakutat bay, of which it is not necessary to give detailed descriptions.
CANOETRIP INDISENCHANTMENTBAY.
CANOETRIP INDISENCHANTMENTBAY.
On July 3, I continued my examination of the region about the head of Yakutat bay by making a canoe trip up Disenchantment bay to Haenke island. With the assistance of Christie and Crumback, our canoe was launched through the surf without difficulty, and we slowly worked our way through the fields of floating ice which covered all the upper portion of the inlet. The men plied the oars with which the canoe was fortunately provided, while I directed its course with a paddle. A heavy swell rolling in from the ocean rendered the task of choosing a route through the grinding ice-pack somewhat difficult. After four or five hours of hard work, during which time several vain attempts were made to traverse leads in the ice which had only one opening, we succeeded in reaching the southern end of the island.
The shores of Haenke island are steep and rocky, and, so far as I am aware, afford only one cove in which a boat can take refuge. This is at the extreme southern point, and is not visible until its entrance is reached. A break or fissure in the rocks there admits of the accumulation of stone and sand, and thishas been extended by the action of the waves and tides until a beach a hundred feet in length has been deposited. The dashing of the bowlders and sand against the cliffs at the head of the cove by the incoming waves has increased its extension in that direction so as to form a well-sheltered refuge. The absence of beaches on other portions of the island is due to the fact that its bordering precipices descend abruptly into deep water, and do not admit of the accumulation of débris about their bases. Without stones and sand with which the waves can work, the excavation of terraces is an exceedingly slow operation. The precipitous nature of the borders of the island is due, to some extent at least, to the abrasion of the rocks by the glacial ice which once encircled it.
Pulling our canoe far up on the beach, we began the ascent of the cliffs. Hundreds of sea birds, startled from their nests by our intrusion, circled fearlessly about our heads and filled the air with their wild cries. The more exposed portions of the slopes were bare of vegetation, but in the shelter of every depression dense thickets obstructed the way. Many of the little basins between the rounded knolls hold tarns of fresh water, and were occupied at the time of our visit by flocks of gray geese. It is evident that the island was intensely glaciated at no distant day. The surfaces of its rounded domes are so smoothly polished that they glitter like mirrors in the sunlight. On the polished surfaces there are deep grooves and fine, hair-like lines, made by the stones set in the bottom of the glacier which once flowed over the island and removed all of the rocks that were not firm and hard. On many of the domes of sandstone there rest bowlders of a different character, which have evidently been brought from the mountains toward the northeast.
The summit of the island is about 800 feet above the level of the sea, and, like its sides, is polished and striated. The terraces on the mountains of the mainland show that the glacier which formerly flowed out from Disenchantment bay must have been fully 2,000 feet deep. The bed it occupied toward the south is now flooded by the waters of Yakutat bay.
At the time of Malaspina's visit, 100 years ago, the glaciers from the north reached Haenke island, and surrounded it on three sides.27At the rate of retreat indicated by comparingMalaspina's records with the present condition, the glaciers must have reached Point Esperanza, at the mouth of Disenchantment bay, about 200 years ago; and an allowance of between 500 and 1,000 years would seem ample for the retreat of the glaciers since they were at their flood.
27The map accompanying Malaspina's report and indicating these conditions has already been mentioned, and is reproduced onplate 7, page 67.
Reaching the topmost dome of Haenke island, a wonderful panorama of snow-covered mountains, glaciers, and icebergs lay before us. The island occupies the position of the stage in a vast amphitheatre; the spectators are hoary mountain peaks, each a monarch robed in ermine and bidding defiance to the ceaseless war of the elements. How insignificant the wanderer who confronts such an audience, and how weak his efforts to describe such a scene!
From a wild cliff-enclosed valley toward the north, guarded by towering pinnacles and massive cliffs, flows a great glacier, the fountains of which are far back in the heart of the mountains beyond the reach of vision. Having vainly sought an Indian name for this ice-stream, I concluded to christen it theDalton glacier, in honor of John Dalton, a miner and frontiersman now living at Yakutat, who is justly considered the pioneer explorer of the region. The glacier is greatly shattered and pinnacled in descending its steep channel, and on reaching the sea it expands into a broad ice-foot. The last steep descent is made just before gaining the water, and is marked by crevasses and pinnacles of magnificent proportion and beautiful color. This is one of the few glaciers in the St. Elias region that has well-defined medial and lateral moraines. At the bases of the cliffs on the western side there is a broad, lateral moraine, and in the center, looking like a winding road leading up the glacier, runs a triple-banded ribbon of débris, forming a typical medial moraine. The morainal material carried by the glacier is at last deposited at its foot, or floated away by icebergs, and scattered far and wide over the bottom of Yakutat bay.
The glacier expands on entering the water, as is the habit of all glaciers when unconfined, and ends in magnificent ice-cliffs some two miles in length. The water dashing against the bases of the cliffs dissolves them away, and the tides tend to raise and lower the expanded ice-foot. The result is that huge masses, sometimes reaching from summit to base of the cliffs, are undermined, and topple over into the sea with a tremendous crash. Owing to the distance of the glacier from Haenke island, we couldsee the fall long before the roar reached our ears; the cliffs separated, and huge masses seemed to sink without a sound; the spray thrown up as the blue pinnacles disappeared ascended like gleaming rockets, sometimes as high as the tops of the cliffs, and then fell back in silent cataracts of foam. Then a noise as of a cannonade came rolling across the waters and echoing from cliff to cliff. The roar of the glacier continues all day when the air is warm and the sun bright, and is most active when the summer days are finest. Sometimes, roar succeeded roar, like artillery fire, and the salutes were answered, gun for gun, by the great Hubbard glacier, which pours its flood of ice into the fjord a few miles further northeastward. This ice-stream, most magnificent of the tide-water glaciers of Alaska yet discovered, and a towering mountain peak from which the glacier receives a large part of its drainage, were named in honor of Gardiner G. Hubbard, president of the National Geographic Society.
Hubbard Glacier
Hubbard Glacier
Looking across the waters of the bay, whitened by thousands of floating bergs, we could see three miles of the ice-cliffs formed where the Hubbard glacier enters the sea. A dark headland on the shore of the mainland to the right shut off the full view of the glacier but formed a strongly drawn foreground, which enhanced the picturesque effect of the scenery. The Hubbard glacier flows majestically through a deep valley leading back into the mountains, and has two main branches, with a smaller and steeper tributary between. These branches unite to form a single ice-foot extending into the bay. The western branch has a dark medial moraine down its center, which makes a bold, sweeping curve before joining the main stream. There is also a broad lateral débris-belt along the bases of the cliffs forming its right bank. The whole surface of the united glacier, and all of the white tongues running back into the mountains beyond the reach of vision, are broken and shattered, owing to the steepness and roughness of the bed over which they flow. The surface, where not concealed by morainal material, is snow-white; but in the multitude of crevasses the blue ice is exposed, and gives a greenish-blue tint to the entire stream. Where the subglacial slopes are steep, the ice is broken into pinnacles and towers of the grandest description.
On the steep mountain sides sloping toward the Hubbard glacier there are more than a dozen secondary ice-streams which are tributary to it. The amphitheatres in which the glacier hasits beginnings have never been seen; but our general knowledge of the fountains from which glaciers flow assures us that not only scores but hundreds of other secondary and tertiary glaciers far back into the mountains contribute their floods to the same great stream.
After being received on board theCorwin, late in September, we had an opportunity to view the great sea-cliffs of the Hubbard glacier near at hand. Captain Hooper, attracted by the magnificent scenery, took his vessel up Disenchantment bay to a point beyond Haenke island, whence a view could be had of the eastern extension of the inlet. So far as is known, theCorwinwas the first vessel to navigate those waters. Soundings made between the island and the ice-foot gave forty to sixty fathoms. At the elbow, where the southeastern shore of the bay turns abruptly eastward, there is a low islet not represented on any map previous to the one made by the recent expedition, which commands even a wider prospect than can be obtained from Haenke island. Future visitors to this remote coast should endeavor to reach this islet, after having beheld the grand panorama obtainable from the summit of Haenke island. The portion of Disenchantment bay stretching eastward from the foot of Hubbard glacier is enclosed on all sides by bold mountains, the lower slopes of which have the subdued and flowing outlines characteristic of glaciated regions. Several glaciers occur in the high-grade lateral valleys opening from the bay; but these have recently retreated, and none of them have sufficient volume at present to reach the water. The general recession, in which all the glaciers of Alaska are participating, is manifested here by the broad débris fields, which cover all the lower ice-streams not ending in the sea. The absence of vegetation on the smooth rocks recently abandoned by the ice also tells of recent climatic changes.
A débris-covered glacier, so completely concealed by continuous sheets of stones and earth that its true character can scarcely be recognized, descends from the mountains just east of Hubbard glacier. It is formed by the union of two principal tributaries, and, on reaching comparatively level ground, expands into a broad ice-foot, but does not have sufficient volume to reach the sea. Another glacier, of smaller size but of the same general character, lies between the Hubbard and Dalton glaciers.
In a rugged defile in the mountains just west of Haenke island there is another small dirt-covered glacier, which creeps down from the precipices above and reaches within a mile of the water.At its end there is a cliff of black, dirty ice, scarcely to be distinguished from rock at a little distance, from the base of which flows a turbid stream. This glacier is covered so completely with earth and stones that not a vestige of the ice can be seen unless we actually traverse its surface. Its appearance suggests the name ofBlack glacier, by which it is designated on the accompanying map.
The visitor to Haenke island has examples of at least two well-marked types of glaciers in view: The small débris-covered ice-streams, too small to reach the water, are typical of a large class of glaciers in southern Alaska, which are slowly wasting away and have become buried beneath débris concentrated at the surface by reason of their own melting. The Galiano glacier is a good example of this class. The Hubbard and Dalton glaciers are fine examples of another class of ice-streams which flow into the sea and end in ice-cliffs, and which for convenience we calltide-water glaciers. Nowhere can finer or more beautiful examples of this type be found than those in view from Haenke island.
The formation of icebergs from the undermining and breaking down of the ice-cliffs of the tide-water glaciers has already been mentioned. But there is another method by which bergs are formed—a process even more remarkable than the avalanches that occur when portions of the ice-cliffs topple over into the sea. The ice-cliffs at the foot of the tide-water glaciers are really sea-cliffs formed by the waves cutting back a terrace in the ice. The submerged terrace is composed of ice, and may extend out a thousand feet or more in front of the visible part of the ice-cliffs. These conditions are represented in the accompanying diagram (figure 1), which exhibits a longitudinal section of the lower end of a tide-water glacier where it pushes out into the sea.
As the sea-cliff of ice recedes and the submerged terrace increases in breadth there comes a time when the buoyancy of theice at the bottom exceeds its strength, and pieces break off and rise to the surface. The water about the ends of the glaciers is so intensely muddy that the submerged ice-foot is hidden from view, and its presence would not be suspected were it not for the fragments occasionally rising from it. The sudden appearance of these masses of bottom ice at the surface is always startling. While watching the ice-cliffs and admiring the play of colors in the deep crevasses which penetrate them in every direction, or tracing in fancy the strange history of the silent river and wondering in what age the snows fell on the mountains, which are now returning to their parent, the sea, one is frequently awakened by a commotion in the waters below, perhaps several hundred feet in front of the ice-cliffs. At first it seems as if some huge sea-monster had risen from the deep and was lashing the waters into foam; but soon the waters part, and a blue island rises to the surface, carrying hundreds of tons of water, which flows down its sides in cataracts of foam. Some of the bergs turn completely over on emerging, and thus add to the tumult and confusion that attends their birth. The waves roll away in widening circles, to break in surf on the adjacent shores, and an island of ice of the most lovely blue floats serenely away to join the thousands of similar islands that have preceded it. The fragments of the glacier rising from the bottom in this manner are usually larger than those broken from the faces of the ice-cliffs, sometimes measuring 200 or 300 feet in diameter. Their size and the suddenness with which they rise would insure certain destruction of a vessel venturing too near the treacherous ice-walls.
At the time of our visit to Haenke island, the entire surface of Disenchantment bay and all of Yakutat bay as far southward as we could see formed one vast field of floating ice. Most of the bergs were small, but here and there rose masses which measured 150 by 200 feet on their sides and stood 40 or 50 feet out of the water. The bergs are divided, in reference to color, into three classes—the white, the blue, and the black. The white ones are those that have fallen from the face of the ice-walls or those that have been sufficiently exposed to the atmosphere to become melted at the surface and filled with air cavities. The blue bergs are of many shades and tints, finding their nearest match in color in Antwerp blue. These are the ones that have recently risen from the submerged ice-foot, or have turned over owing to a change of position in the center of gravity. Rapid as is themelting of the ice when exposed to the air, it seems to liquefy even more quickly when submerged. The changes thus produced finally cause the bergs to reverse their positions in the water. This is done without the slightest warning, and is one of the greatest dangers to be guarded against while canoeing among them. The white color presented by the majority of the bergs is changed to blue when they become stranded, and the surf breaks over them and dissolves away their porous surfaces. A few of the bergs are black in color, owing to the dirt and stones that they carry on their surfaces or frozen in their mass. Quantities of débris are thus floated away from the tide-water glaciers and strewn over the bottoms of the adjacent inlets.
This digression may be wearisome, but one cannot stand on Haenke island without wishing to know all the secrets of the great ice-streams that flow silently before him.
Returning from our commanding station at the summit of the island to where we left our canoe, we were surprised and not a little startled to find that the tide had run out and left the strand between our canoe and the water completely blocked with huge fragments of ice. There was no way left for us to launch our canoe except by cutting away and leveling off the ice with our axe, so as to form a trail over which we could drag it to the water. This we did, and then, poising the canoe on a low flat berg, half of which extended beneath the water, I took my place in it with paddle in hand, while Christie and Crumback, waiting for the moment when a large wave rolled in, launched the canoe far out in the surf. By the vigorous use of my paddle I succeeded in reaching smooth water and brought the canoe close under the cliff forming the southern side of the cove, where the men were able to drop in as a wave rolled under us.
We slowly worked our way down the bay through blue lanes in the ice-pack, against an incoming tide, and reached our tents near sunset. Thus ended one of the most enjoyable and most instructive days at Yakutat bay.
FROMYAKUTATBAY TOBLOSSOMISLAND.
FROMYAKUTATBAY TOBLOSSOMISLAND.
Our camp on the shore of Yakutat bay was held for several days after returning from Haenke island, but in the meantime an advance-camp was established on the side of the Lucia glacier, from which Mr. Kerr and myself made explorations ahead.
Before leaving the base-camp I visited Black glacier for the purpose of taking photographs and studying the appearance of an old glacier far spent and fast passing away. This, like the Galiano glacier, is a good example of a great number of ice-streams in the same region which are covered from side to side with débris. The cañon walls on either side rise precipitously, and their lower slopes, for the height of 200 or 300 feet, are bare of vegetation. The surface of the glacier has evidently sunken to this extent within a period too short to allow of the accumulation of soil and the rooting of plants on the slopes. The banks referred to are in part below the upper limit of timber growth, and the adjacent surfaces are covered with bushes, grasses, and flowers. Under the climatic conditions there prevailing, it is evident that the formation of soil and the spreading of plants over areas abandoned by ice is a matter of comparatively few years. It is for this reason that a very recent retreat of Black glacier is inferred. Many of the glaciers in southern Alaska give similar evidence of recent contraction, and it is evident that a climatic change is in progress which is either decreasing the winter's snow or increasing the summer's heat. The most sensitive indicators of these changes, responding even more quickly than does the vegetation, are the glaciers.
The fourth of July was spent by us in cutting a trail up the steep mountain slope to the amphitheatre visited during my first tramp. No one can appreciate the density and luxuriance of the vegetation on the lower mountain in that region until he has cut a passage through it. Seven men, working continuously for six or seven hours with axes and knives, were able to open a comparatively good trail about a mile in length. The remainder of the way was along stream courses and up bowlder-washes, which were free from vegetation. In the afternoon, having finished our task, a half-holiday was spent in an exciting search for two huge brown bears discovered by one of the party, but they vanished before the guns could be brought out.
The next day an advance-camp was made in the amphitheatre above timber line, and there Mr. Kerr and myself passed the night, molested only by swarms of mosquitoes, and the day following occupied an outstanding butte as a topographical station. In the afternoon of the same day the advance-camp was moved to the border of the Atrevida glacier at a point already described, where a muddy stream gushes out from under the ice.
Our next advance-camp, established a few days later, was at Terrace point, as we called the extreme end of the mountain spur separating the Lucia and Atrevida glaciers. These ice-streams were formerly much higher than now, and when at their flood formed terraces along the mountain side, which remain distinctly visible to the present day. The space between the two glaciers at the southern end of the mountain spur became filled with bowlders and stones carried down on the side of the ice-streams, and, as the glaciers contracted, added a tapering point to the mountain. Between the present surface of the ice and the highest terrace left at some former time there are many ridges, sloping down stream, which record minor changes in the fluctuation of the ice. A portion of one of these terraces is seen to the left in plate 10.
Wall of ice
Wall of ice
Terrace point, like all the lower portions of the mountain spurs extending southward from the main range, is densely clothed with vegetation, and during the short summers is a paradise of flowers. Our tent was pitched on a low terrace just beyond the border of the ice. The steep bluff rising to an elevation of some 200 feet on the east of our camp was formed by glacial ice buried beneath an absolutely barren covering of stones and dirt. On the west the ascent was still more precipitous, but the slope from base to summit was one mass of gorgeous flowers.
Atrevida Glacier
Atrevida Glacier
Kerr and myself made several excursions from the camp at Terrace point, and explored the country ahead to the next mountain spur for the purpose of selecting a site for another advance-camp. In the meantime the men were busy in bringing up supplies.
Our reconnoissance westward took us across the Lucia glacier to the mouth of a deep, transverse gorge in the next mountain spur. The congeries of low peaks and knobs south of this pass we named theFloral hills, on account of the luxuriance of the vegetation covering them; and the saddle separating them from the mountains to the north was calledFloral pass.
In crossing the Lucia glacier we experienced the usual difficulties met with on the débris-covered ice-field of Alaska. The way was exceedingly rough, on account of the ridges and valleys on the ice, and on account of the angular condition of the débris resting upon it. Many of the ridges could not conveniently be climbed, owing to the uncertain footing afforded by the angularstones resting on the slippery slope beneath. Fortunately, the crevasses were mostly filled with stones fallen from the sides, so that the danger from open fissures, which has usually to be guarded against in glacial excursions, was obviated; yet, as is usually the case when crevasses become filled with débris, the melting of the adjacent surfaces had caused them to stand in relief and form ridges of loose stones, which were exceedingly troublesome to the traveler.
Ice tunnel
Ice tunnel
Near the western side of the Lucia glacier, between Terrace point and Floral pass, there is a huge rounded dome of sandstone rising boldly out of the ice. This corresponds to the "nunataks" of the Greenland ice-fields, and was covered by ice when the glaciation was more intense than at present. On the northern side of the island the ice is forced high up on its flanks, and is deeply covered with moraines; but on the southwestern side its base is low and skirted by a sand plain deposited in a valley formerly occupied by a lake. The melting of the glacier has, in fact, progressed so far that the dome of rock is free from ice on its southern side, and is connected with the border of the valley toward the west by the sand plain. This plain is composed of gravel and sand deposited by streams which at times became dammed lower down and expanded into a lake. Sunken areas and holes over portions of the lake bottom show that it rests, in part at least, upon a bed of ice.
Lake bed delta
Lake bed delta
The most novel and interesting feature in the Lucia glacier is a glacial river which bursts from beneath a high archway of ice just at the eastern base of the nunatak mentioned above, and flows for about a mile and a half through a channel excavated in the ice, to then enter the mouth of another tunnel and become lost to view. An illustration of this strange river and of the mouth of the tunnel in the débris-covered ice into which it rolls, reproduced from a photograph by a mechanical process, is given on plate 14, and another view of the mouth of the same tunnel is presented in the succeeding plate. This is the finest example of a glacial river that it has ever been my good fortune to examine.
Lucia Glacier river
Lucia Glacier river
The stream is swift, and its waters are brown and heavy with sediment. Its breadth is about 150 feet. For the greater part of its way, where open to sunlight, it flows between banks of ice and over an icy floor. Fragments of its banks, and portions ofthe sides and roof of the tunnel from which it emerges, are swept along by the swift current, or stranded here and there in midstream. The sand plain already mentioned borders the river for a portion of its course, and is flooded when the lower tunnel is obstructed.
Glacial tunnel
Glacial tunnel
The archway under which the stream disappears is about fifty feet high, and the tunnel retains its dimensions as far as one can see by looking in at its mouth. Where the stream emerges is unknown; but the emergence could no doubt be discovered by examining the border of the glacier some miles southward. No explorer has yet been bold enough to enter the tunnel and drift through with the stream, although this could possibly be done without great danger. The greatest risk in such an undertaking would be from falling blocks of ice. While I stood near the mouth of the tunnel there came a roar from the dark cavern within, reverberating like the explosion of a heavy blast in the chambers of a mine, that undoubtedly marked the fall of an ice mass from the arched roof. The course of the stream below the mouth of the tunnel may be traced for some distance by scarps in the ice above, formed by the settling of the roof. Some of these may be traced in the illustrations. When the roof of the tunnel collapses so completely as to obstruct the passage, a lake is formed above the tunnel, and when the obstruction is removed the streams draining the glacier are flooded.
At the mouth of the tunnel there are always confused noises and rhythmic vibrations to be heard in the dark recesses within. The air is filled with pulsations like deep organ notes. It takes but little imagination to transform these strange sounds into the voices and songs of the mythical inhabitants of the nether regions.
Toward the right of the tunnel, as shown on plate 14, there appears a portion of the former river bed, now abandoned, owing to the cutting across of a bend in the stream. The floor of this old channel is mostly of clear, white ice, and has a peculiar, hummocky appearance, which indicates the direction of the current that once flowed over it. A portion of the bed is covered with sand and gravel, and along its border are gravel terraces resting on ice. These occurrences illustrate the fact that rivers flowing through channels of ice are governed by the same general laws as the more familiar surface streams.
After examining this glacial river, during our first excursion on the Lucia glacier, we reached its western banks by crossingabove the upper archway. Traversing the sand plain to the westward, we came to another stream of nearly equal interest, flowing along the western margin of the glacier, past the end of the deep gorge called Floral pass. A small creek, flowing down the pass, joins the stream and skirts the glacier just below the mouth of a wild gorge on the side of the main valley. This stream once flowed along the border of the Lucia glacier when it was much higher than now, and began the excavation of a channel in the rock, which was retained after the surface of the glacier was lowered by melting. It still flows in a rock-cut channel for about a mile before descending to the border of the glacier as it exists at present. The geologist will see at once that this is a peculiar example of superimposed drainage. The gorge cut by the stream is a deep narrow trench with rough angular cliffs on either side, and is a good example of a water-cut cañon. When the Lucia glacier melts away and leaves the broad-bottomed valley clear of ice, the deep narrow gorge on its western side, running parallel with its longer axes, but a thousand feet or more above its bottom, will remain as one of the evidences of a former ice invasion.
During our reconnoissance we turned back at the margin of the second river, but a day or two later reached the same point with the camp hands and camping outfit, and, placing a rope from bank to bank, effected a crossing. Our next camp was in Floral pass. From there we occupied a topographical station on the summit of the Floral hills, and made another reconnoissance ahead, across theHayden glacier,28to the next mountain spur.
28Named in honor of the late Dr. Ferdinand V. Hayden, founder of the United States Geological Survey of the Territories.
Floral pass, like so many of the topographical features examined during the recent expedition, has a peculiar history. It is a comparatively low-grade gorge leading directly across the end of an angular mountain range forming one of the spurs of Mount Cook. The position of the pass was determined by an east-and-west fault and by the erosion of soft shales turned up on edge along the line of displacement. At its head it is shut in by the Hayden glacier, which flows past it and forms a wall of ice about two hundred feet high. The water flowing out from beneath the side of the glacier forms a muddy creek, which finds its way over a bowlder-covered bed in the bottom of the gorge to the border of Lucia glacier. Along the sides of the gorge there aremany terraces, which record a complicated history. Evenly stratified clays near its lower end, adjacent to the Lucia glacier, show that it was at one time occupied in part by a lake. Above the lacustral beds there are water-worn deposits, indicating that at a later date the gorge was filled from side to side by moraines and coarse stream deposits several hundred feet thick. These were excavated, and portions were left clinging to the hill-sides, forming the terraces of to-day. Diverse slopes in the terraces suggest that the drainage may at times have been reversed, according as the Lucia or the Hayden glacier was the higher.
The routes between our various camps, scattered along between Yakutat bay and Blossom island, were traversed several times by every member of the party. To traverse the same trail several times with heavy loads, and perhaps in rain and mist, is disheartening work which I will spare the reader the effort of following even in fancy.
From our camp in Floral pass another reconnoissance ahead was made by Mr. Kerr and myself, as already mentioned. These advances, each one of which told us something new, were the most interesting portions of our journey. The little adventures and experiences of each advance were reported and talked over when we rejoined our companions around the camp-fire at night, and were received with gratifying interest by the men.
A view of the Hayden glacier from the Floral hills showed us that it differed from any of the glaciers previously traversed. Its surface, where we planned to cross it, was free of débris except along the margins and also near the center, where we could distinguish a light medial moraine. Farther southward, near the terminus of the glacier, its surface from side to side was buried beneath a sheet of stones and dirt. As in many other instances, the débris on the lower portion of the glacier has been concentrated at the surface, owing to the melting of the ice, so as to form a continuous sheet.
Early one morning, while traveling over the torrent-swept bowlders in the stream-bed on our way up Floral pass, we were a little startled at seeing the head of a bear just visible through the flowers fringing the bank. Before a shot could be fired, he vanished, and remained perfectly quiet among the bushes for several minutes. But a trembling of the branches at length betrayed his presence, and a few minutes later he came out in full view, his yellow-brown coat giving him the appearance of a hugedog. Standing on a rounded mound he looked inquiringly down the valley, with his shaggy side in full view. I fired—but missed my aim. The unsuccessful hunter always has an excuse for his failure; I had never before used the rifle I carried, and the hair-trigger with which it was provided deceived me. Fortunately for the bear, and probably still more fortunately for me, the bullet went far above the mark. The huge beast vanished again, although the vegetation was not dense, and left us wondering how such a large animal could disappear so quickly and so completely in such an open region. On searching for his tracks, we found that he had traversed for a few rods the plant-covered terrace on which he was first discovered, and then escaped up a lateral gorge to a broader terrace above.
Reaching the head of the Floral pass and climbing the hill of débris bordering the Hayden glacier, we came out upon the clear, white ice of the central portion of the ice-stream. The ice was greatly crevassed, but nearly all the gaps in its surface could be crossed by jumping or else by ice-bridges. The most interesting feature presented by the glacier was the way in which it yields itself to the inequality of the rocks over which it flows. Starting on the eastern side, below the entrance to Floral pass, and extending northwestward diagonally across the stream, there is a line of steep descent in the rocks beneath, which causes the ice to be greatly broken. This is not properly an ice-fall, except near the confining walls of the cañon; but it might be called an ice-rapid. The ice bends down over the subglacial scarp with many long breaks, but does not form pinnacles, as in many similar instances where the descent is greater, and true ice cascades occur. The most practicable way for crossing the glacier was to ascend the stream above the line of rapids for some distance, and then follow diagonally down its center, finally veering westward to the opposite bank. By following this course, and making a double curve like the letterS, we could cross the steep descent in the center, where it was least crevassed.
The marginal moraines on the Hayden glacier are formed of fragments of brown and gray sandstone and black shale of all sizes and shapes. It is clear that this débris was gathered by the cliffs bordering the glacier on either side. The medial moraine which first appears at the surface just above the rapids is of a different character, and tells that the higher peaks of Mount Cook are composed, in part at least, of a different material fromthe spurs projecting from it. The medial moraine looks black from a distance, but, on traversing it, it was found to be composed mainly of dark-green gabbro and serpentine. The débris is scattered over the surface in a belt several rods wide; but it is not deep, as the ice can almost everywhere be seen between the stones. Where the fragments of rock are most widely separated, there are fine illustrations of the manner in which small, dark stones absorb the heat of the sun and melt the ice beneath more rapidly than the surrounding surface, sinking into the ice so as to form little wells, several inches deep, filled with clear water. Larger stones, which are not warmed through during a day's sunshine, protect the ice beneath while the adjacent surface is melted, and consequently become elevated on pillars or pedestals of ice. The stones thus elevated are frequently large, and form tables which are nearly always inclined southward. In other instances the ice over large areas, especially along the center of the medial moraine, was covered with cones of fine, angular fragments from a few inches to three or four feet in height. These were not really piles of gravel, as they seemed, but consisted of cones of ice, sheeted over with thin layers of small stones. The secret of their formation, long since discovered on the glaciers of Switzerland, is that the gravel is first concentrated in a hole in the ice and, as the general surface melts away, acts like a large stone and protects the ice beneath. It is raised on a pedestal, but the gravel at the borders continually rolls down the sides and a conical form is the result.
Where we crossed the Hayden glacier it is only about a mile broad in a direct line; but to traverse it by the circuitous route rendered necessary by the character of its surface required about three hours of hard tramping, even when unincumbered with packs. From the center of the glacier a magnificent view may be obtained of the snow-covered domes of Mount Cook, from which rugged mountain ridges stretch southward like great arms and enclose the white snow-field from which the glacier flows. At an elevation of 2,500 feet the icy portion disappears beneath the névé on which not a trace of débris is visible. All the higher portions of the mountains are white as snow can make them, except where the pinnacles and precipices are too steep to retain a covering.
On reaching the western side of the glacier we found a bare space on the bordering cliffs, about a hundred feet high, whichhas been abandoned by the ice so recently that it is not yet grassed over. Above this came the luxuriant and beautiful vegetation covering all the lower mountain slopes.
The mountain spur just west of the glacier, like several of the ridges stretching southward from the higher mountains, ends in a group of hills somewhat separate from the main ridge. The hills are covered with a rank vegetation, and in places support a dense growth of spruce trees. Reaching the grassy summit, we had a fine, far-reaching view of the unexplored region toward the west, and of the vast plateau of ice stretching southward beyond the reach of the vision. West of our station, another great ice-stream, named theMarvine glacier, in honor of the late A. R. Marvine, flows southward with a breadth exceeding that of any of the icy streams yet crossed. Beyond the Marvine glacier, and forming its western border, there is an exceedingly rugged mountain range trending northeast and southwest. Although this is, topographically, a portion of the mountain mass forming Mount Cook, its prominence and its peculiar geological structure render it important that it should have an independent name. In acknowledgment of the services to science rendered by the first state geologist of Massachusetts, it is designated theHitchcock rangeon our maps. Rising above the angular crest line of this mountain mass towers the pyramidal summit of Mount St. Elias, seemingly as distant as when we first beheld it from near Yakutat bay.
About a mile west of the hill on which we stood, and beyond the bed of a lake now drained of its waters by a tunnel leading southward through the ice, rose a steep, rocky island out of the glaciers, its summit overgrown with vegetation and dark with spruce trees. This oasis in a sea of ice, subsequently named Blossom island, we chose as the most favorable site for our next advance-camp.
We then returned to our camp in Floral pass, and a day or two later Kerr and Christie started on a side trip up the Hayden glacier, to be absent five days. During this trip the weather was stormy, and only allowed half an hour for topographical work when a somewhat favorable station was reached. This was of great service, however, in mapping the country, as it gave a station of considerable elevation on the side of Mount Cook. The trip was nearly all above the snow-line, and was relieved by many novel experiences.