Pushing on toward the western border of the glacier, across the barren field of stones, I came at length to the brink of a precipice of dirty ice more than a hundred feet high, at the foot of which flowed a swift stream of turbid water. A few hundred yards below, this stream suddenly disappeared beneath an archway formed by the end of a glacial tunnel, and its further course was lost to view. It was a strange sight to see a swift, foaming river burst from beneath overhanging ice-cliffs, roar along over a bowlder-covered bed, and then plunge into the mouth of a cavern, leaving no trace of its lower course except a dull, heavy rumbling far down below the icy surface. A still grander example of these glacial streams, observed a few days later, is described on another page. The bank of the gulf opposite the point at which I first reached it is formed by a steep mountain-side supporting a dense growth of vegetation. Here and there, however, streams of water plunge down the slope, making a chain of foaming cascades, and opening the way through the vegetation. It seemed practicable to traverse one of these stream beds without great difficulty, and thus to reach the plateau which I knew, from a more distant view, to exist above. {91} 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.