So they pushed open the door, which was fastened but not locked, and stepped inside. The cabin contained but a single large room furnished with several sleeping bunks, a stout table, and a number of seats, all home-made from unplaned lumber. Much rubbish, including empty bottles and tin cans, was scattered about; but it was evident that everything of value had been removed by the last occupants. The chief feature of the room was an immense and rudely artistic fire-place at its farther end. Above this hung a smooth board skilfully decorated with charcoal sketches, and bearing the legend "Camp Muir." As Serge caught sight of this he uttered an exclamation. "Now I know where we are!" he cried. "Come with me, Phil, and I will show you one of the grand sights of the world." With this he dashed out of the door, and ran toward the beach ridge behind which the cabin stood. Phil followed, wondering curiously what his friend could mean. As they reached the low crest of the ridge he understood; for outspread before him, bathed in a rosy light by the setting sun, was a spectacle that tourists travel from all parts of the world to gaze upon. A precipitous line of ice cliffs of marble whiteness or heavenly blue, two miles long and hundreds of feet in height, carved into spires, pinnacles, minarets, and a thousand other fantastic shapes, rose in frozen majesty at the head of a little bay whose waters washed the beach at their feet. Ere either of the boys could find words to express his delight and wonder, a huge mass of the lofty wall broke away and plunged into the sea, with a thunderous roar that echoed and re-echoed from the enclosing mountains. For a moment it disappeared in a milky cloud of foam and spray. Then it shot up from the depths like some stupendous submarine monster, and with torrents of water streaming from it in glittering cascades, floated on the heaving surface a new-born iceberg. "It must be a glacier," said Phil, in an awe-stricken tone. "It is a glacier," answered Serge, triumphantly, "and one of the most famous in the world, for it is the Muir, which is larger and contains more ice than all the eleven hundred glaciers of Switzerland put together. That cabin is the one occupied by John Muir and his companions when they explored it in 1890. To think that we should have come down one of its branches, and even crossed the great glacier itself without knowing what it was! I believe we would have known it, though, if the snow hadn't been so deep as to alter the whole character of its surface." "If this is the Muir Glacier," reflected Phil, "I don't see but what we are in a box. We must be to the westward of Chilkat." "Yes," said Serge. "It lies to the eastward of those mountains." "Which don't look as though they would be very easy even for us to climb, while I know we couldn't get Jalap and Nel-te over them. I don't suppose any tourist steamers will be visiting this place for some time, either."