At its lower end it is but a few feet above the lake surface, covered with glacial drift modified by water, and diversified, especially on its western side, by debris ridges, the moraines of glaciers which continued to flow into the valley or into the Lake long after the main glacier, of which they were once tributaries, had dried up.

On approaching the south end of the Lake by steamer, I had observed these long ridges, divined their meaning, and determined on a closer acquaintance.

While staying at the Tallac House I repeatedly visited them and explored the canyons down which their materials were brought.

I proceed to describe them.
_Fallen Leaf Lake Glacier_.

Fallen Leaf Lake lies on the plain of Lake Valley, about one and a half miles from Lake Tahoe, its surface but a few feet above the level of the latter Lake[2]; but its bottom far, probably several hundred feet, below that level.