No. 1.— Glaciation of the Sawatch Range, Colorado. 
By W. M. Davis. 
Tur accompanying sketches of La Plata peak and the valleys of 
the Sawatch range in the Rocky mountains of Colorado emphasize 
better than long descriptions the essential features of a glaciated moun- 
tain mass. The Sawatch range lies west of the upper Arkansas valley, 
and includes the three college peaks, Mts. Harvard, Yale, and Prince- 
ton, the first two of which were ascended by a small party led by 
Prof. J. D. Whitney in 1869, when I accompanied him as a student. 
A number of the summits exceed 14,000 feet by several hundreds; 
Mt. Harvard (14,375’) was for several years considered the highest 
of the Rocky mountains in the United States, until Blanca peak 
(14,390’) was given that rank; and now Mt. Elbert, in the Sawatch 
range a score of miles north of Mt. Harvard, is placed first in the list, 
with an altitude of 14,436 feet. 
The summer of 1904 gave me an opportunity of making a brief 
visit, with Prof. L. G. Westgate as a companion, to that part of the 
Sawatch range near Twin Lakes on Lake creek, which comes from a 
fine glaciated valley between Mts. Elbert and La Plata, and flows 
eastward into the Arkansas river. The village of Twin Lakes (called 
Dayton on the Leadville map sheet) is a picturesque and attractive 
center for excursions, easily reached by stage from Granite station on 
the Rio Grande Western and the Colorado Midland railroads. Pro- 
fessor Westgate returned here after our joint excursion to Utah, and 
continued for a month the studies that we had begun together; his 
report on the district, with special reference to the two or more epochs 
of glaciation there recorded, is published in the Journal of Geology. 
The general view of La Plata peak, figure 1, looking southwest, 
is taken from one of the southwest spurs of Mt. Elbert, at a height 
of about 13,000 feet. A photographic view from about the same 
point is given in the Plate (A). The broadly open valley or trough 
of the Lake creek glacier lies beneath the foreground spurs, and its 
farther slopes truncate several spurs of the La Plata mass. Crystal 
lake gulch opens its well rounded floor sharply on the south wall of 
the larger and deeper trough of Lake creek, the difference of level of 
the two trough floors being about 800 feet, as determined by aneroid 
measurement. The notable features of the view, besides the clearly 
defined hanging valley or trough, are:—the sharp summits of La 
