6 PHILOSOPHICAL SOCIETY OF WASHINGTON. 
one of the tributaries of Mono Lake. The Mt. Dana glacier is approx- 
imately 2,500 feet long and of somewhat greater breadth. Although 
small, and in fact but a “ pocket edition” of what may be seen on 
a far grander scale in many mountains, yet it is a veritable glacier, 
with nearly all the features that characterize such ice-bodies 
in other countries. The distinction between the snow-ice of the 
névé and the more solid blue or greenish-blue ice of the glacier 
proper is clearly marked—as was observed to be the case also 
in a number of neighboring glaciers. An irregular open fissure 
crosses the head of the névé, corresponding to the “ bergschrund ” 
of the Swiss glaciers, while a number of parallel fractures on the 
border of the glacier at the foot of the snow-field form marginal 
crevasses with walls of solid blue ice. Near the terminus of the 
glacier alternating sheets of porous, white ice, and of more compact 
bluish ice were observed, which produce a distinct laminated or 
ribboned structure. Dirt-bands were plainly visible, sweeping 
in undulating lines across the surface of the glacier; and similar 
bands are a conspicuous feature in nearly all the ice-bodies seen in the 
High Sierra. About the foot of the Mt. Dana glacier a true terminal 
moraine is now in process of formation. The fall of stones and 
dirt from the ice onto the moraine was noticed many times during 
our visits. Some of the rounded stones from beneath the ice are 
battered and scratched and have evidently received these markings 
within the past few years. 
On the northern side of Mt. Lyell another glacier was visited, 
which is the source of the Tuolumne river. The Mt. Lyell glacier is 
somewhat larger than the one on Mt. Dana, and, like it, exhibits 
characteristic glacial phenomena. A protrusion of compact, banded 
ice from beneath a snow-field at the head of an amphitheatre was 
here again observed, as well as the presence of moraines, crevasses, 
dirt-bands, ete. On the lower portion of this glacier were observed 
“ice-pyramids”’ of the form represented in the figure on the follow- 
ing page. 
At the northern base of a pyramid there invariably occurs a 
stone or a mass of dirt, that is depressed below the general surface 
of the glacier, as is indicated in the sketch. The pyramid invariably 
points toward the noon-day sun. IJts mass is composed of porous 
and banded ice, like that forming the general surface of the glacier, 
but its northern face is sheeted with compact, bluish ice. The 
