and decided that he was migrating from the valley below, overstocked
with rabbits as it was, and had taken a wrong direction for his purpose.
Unless the ambition for first ascents have reached the leporidae, this
seems the only explanation.

At this camp at the head of the glacier we saw ptarmigan on several
occasions, and heard their unmistakable cry on several more, and once we
felt sure that a covey passed over the ridge above us and descended to
the other glacier. It was always in thick weather that these birds were
noticed at the glacier head, and we surmised that perhaps they had lost
their way in the cloud.

But even this was not the greatest height at which bird life was
encountered. In the Grand Basin, at sixteen thousand five hundred feet,
Walter was certain that he heard the twittering of small birds familiar
throughout the winter in Alaska, and this also was in the mist. I have
never known the boy make a mistake in such matters, and it is not
essentially improbable. Doctor Workman saw a pair of choughs at
twenty-one thousand feet, on Nun Kun in the Himalayas.

[Sidenote: Avalanches]

Our situation on the glacier floor, much of the time enveloped in dense
mist, was damp and cold and gloomy. The cliffs around from time to time
discharged their unstable snows in avalanches that threw clouds of snow
almost across the wide glacier. Often we could see nothing, and the
noise of the avalanches without the sight of them was at times a little
alarming. But the most notable discharges were those from the great
ice-fall, and the more important of them were startling and really very
grand sights. A slight movement would begin along the side of the ice,
in one of the gullies of the rock, a little trickling and rattling.
Gathering to itself volume as it descended, it started ice in other
gullies and presently there was a roar from the whole face of the
enormous hanging glacier, and the floor upon which the precipitation
descended trembled and shook with the impact of the discharge. Dense
volumes of snow and ice dust rose in clouds thousands of feet high and
slowly drifted down the glacier. We had chosen our camping-place to be
out of harm's way and were really quite safe. We never saw any large
masses detached, and by the time the ice reached the glacier floor it
was all reduced to dust and small fragments. One does not recall in the
reading of mountaineering books any account of so lofty an ice-fall.

[Illustration