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 which it is closely associated—the Chilkat river lies between them—is the St Elias Range (a term now used to include not only the mountains between Cross Sound and Mt. St Elias, but the Chugach, Kenai, Skolai and Nutzotin mountains); among its peaks are: Mt. Crillon (15,900 ft.), Mt. Fairweather (15,290 ft.), Mt. Vancouver (15,666 ft.), Mt. Wrangell (17,500 ft., an active volcano) in the Nutzotin Mountains, Mt. St Elias (18,024 ft.) and, in Canadian territory, Mt. Logan (19,539 ft.). The Aleutian Range, of whose crest the Aleutian Islands are remnants, fills out the system near the coast. The Alaskan Range, connecting with the Nutzotin and Skolai branches of the St Elias Range, lies a little farther inland; it is splendidly marked by many snowy peaks, including Mt. Foraker (17,000 ft.) and Mt. McKinley. The latter, which on the W. rises abruptly out of a marshy country, offers the obstacles of magnificent, inaccessible granite cliffs and large glaciers to the mountaineer; it is the loftiest peak in North America (ca. 20,300 ft.). In the Alaskan Range and the Aleutian Range there are more than a dozen live volcanoes, several of them remarkable; the latter range is composed largely of volcanic material. Evidences of very recent volcanic activity are abundant about Cook Inlet. The Rocky Mountain system extends from Canada (the Yukon territory) into N.E. Alaska, which it crosses near the Arctic Coast in a broad belt composed of several ranges about 6000 ft. in altitude. There is no well-defined crest line; the axis of the system is roughly parallel to the Pacific Mountain system, but runs more nearly E. and W. in Alaska. Between the Pacific Mountain and the Rocky Mountain systems lies the vast Central Plateau region, or Yukon plateau. Finally, between the Rocky Mountains and the Arctic Ocean is the Arctic Slope region, a sloping plain corresponding to the interior plains of the United States.

First Physiographic Region.—The Panhandle is remarkably picturesque. The maze of islands, hundreds in number, of the Alexander Archipelago (area about 13,000 sq. m.) are remnants of a submerged mountain system; the islands rise 3000 to 5000 ft. above the sea, with luxuriantly wooded tops and bald, sheer sides scarred with marks of glacial action; the beachless coast is only a narrow ledge between the mountains and the sea, and unlike the coast of Norway, to which in outline it is not dissimilar, is bold, steep and craggy. Through the inner channels, sheltered from the Pacific by the island rampart, runs the “inland passage,” the tourist route northward from Seattle, Washington. The inter-insular straits are carried up into the shore as fjords heading in rivers and glaciers. Thus the Stikine river continues Sumner Strait and the Taku continues Cross Sound. The Stikine, Taku and Alsek rivers all cross the mountains in deep-cut canyons. Everywhere the evidences of glacial action abound. Most remarkable are the inlets known as Portland Canal and Lynn Canal (continuing Chatham Strait). The first is very deep, with precipitous shores and bordering mountains 5000 to 6000 ft. high; the second is a noble fjord 100 m. long and on an average 6 m. wide, with magnificent Alpine scenery. It is subject in winter to storms of extraordinary violence, but is never closed by ice. Both Portland Canal and Lynn Canal are of historical importance, as the question of the true location of the first and the commercial importance to Canada or to the United States of the possession of the second, were the crucial contentions in the disputes over the Alaska-Canadian boundary. At the head of Lynn Canal, the only place on the whole extent of the south-eastern Alaskan coast where a clear-cut waterparting is exhibited between the sea-board and interior drainage, the summits of the highest peaks in the Coast Range are 8000 to 9000 ft. above the sea. White Pass (2888 ft.) and Chilkoot Pass (3500 ft.), at the head of the Lynn Canal, are the gateway to the mining country of the Klondike and Upper Yukon. They are the highest points that one meets in travelling from Skagway along the course of the Yukon to Bering Sea.

Prior to the opening (in August 1900) of the railway between Skagway and White Horse, Canada (110 m.), by way of the White Pass, all transportation to the interior was effected by men and pack-animals (and for a time by a system of telpherage) over these passes and the Chilkat or Dalton trail; the building

of the railway reduced carriage rates to less than a tenth of their former value, and the Chilkat and Chilkoot Passes were no longer used. The coast region above the Panhandle shows on a smaller and diminishing scale the same characteristic features, gradually running into those of the Aleutians. Out of the Alaska and Nutzotin mountains two great rivers flow southward: the Copper, practically unnavigable except for small boats, because of its turbulence and the discharge of glaciers into its waters; and the Susitna, also practically unnavigable. Both of these rivers have their sources in lofty mountain masses, and are swift and powerful streams carrying with them much silt; their passes over the water-parting N. of the Kenai Peninsula are through gorges from 4000 to 10,000 ft. in depth. The Copper, the Susitna and its tributary, the Yentna, as well as the Skwentna, a tributary of the Yentna from the west, all run through picturesque canyons, and their upper courses are characterized by glacial and torrential feeders. Their valleys are well timbered.

The glaciers of the Panhandle and throughout the rest of the Pacific region are most remarkable—extraordinary alike for their number and their size. They lie mainly between 56° and 61° N. lat., in a belt 1000 m. long, of which the central part, some 350 or 500 m. long and 80 m. to 100 m. wide, has been described as one great confluent névé field. Thousands of Alpine glaciers from one to fifteen miles long fill the upper valleys and canyons of the mountains. More than a hundred almost reach the sea, from which they are separated by detrital lowland or terminal moraines. Other glaciers are of the Piedmont type. Greatest of these and of Alaskan glaciers is the Malaspina, a vast elevated plateau of wasting ice, 1500 sq. m. in area (nearly a tenth the area of all Switzerland), touching the sea at only one point, though fronting it for 50 m. behind a fringing foreland of glacial debris. It is fed by Alpine glaciers, among them one of the grandest in Alaska, the Seward, which descends from Mt. Logan. It is more than 50 m. long, and more than 3 m. broad at its narrowest point, and several times in its course flows over cascades, falling hundreds of feet. Of tide-water glaciers the most remarkable is probably the Muir. It has an area of 350 sq. m.; the main trunk, which is 30 to 40 m. broad, is fed by 26 tributaries, 20 of which are each greater than the Mer de Glace, and pushes its bergs into the sea from ice cliffs almost 2 m. wide, standing 100 to 200 ft. above the water, and extending probably 700 to 1000 ft. beneath its surface. It has been calculated that the average daily discharge of the Muir in summer is 30,000,000 cubic ft. Its course, which is only about 13 m., has a slope of 100 ft. per mile, and the main current moves 7 ft. daily. The character of the Muir was greatly altered by an earthquake in 1899. There are some 30 tide-water glaciers—a considerable number of them very noteworthy. The Valdez is 30 m. long and 5000 ft. in altitude. Most of the Alaskan glaciers are receding, but not all of them; and at times there is a general advance. The Muir receded 1.6 m. from 1879–1890, the Childs about 600 yards in 17 years; others over 4, 7 or 10 m. in 20 years.

The (q.v.), like the Alexander Archipelago, are remnants of a submerged mountain system. Their only remarkable features are the volcanoes on the easterly islands, already mentioned.

Continental Alaska.—Continental Alaska in the interior is essentially a vast plateau. “The traveller between the main drainage areas of the interior is struck by the uniform elevation of the interfluminal areas. Rounded hills, level meads and persistent flat-topped ridges, composed of rocks of varying structure, rise to about the same level and give the impression that they are the remnants of a former continuous surface. Occasional limited areas of rugged mountains rise above this level, and innumerable stream valleys have been incised below it; but from the northern base of the St Elias and Alaskan ranges to the southern foothills of the Rocky Mountain system, and throughout their length, the remnants of this ancient level are to be seen. In height it varies from about 5000 ft. close to the bases of the mountain systems to less than 3000 ft. in the vicinity of the