i 877 *J Prof. Hayden's Explorations. 239 
crossed the Sangre de Cristo range by way of Costilla Pass, 
followed the west base of the range northward as far as 
Fort Garland, making a station on Culebra Peak. 
About 6 miles north of Fort Garland is located one of the 
highest and most rugged mountain peaks in the west, called 
Blanca Peak, the principal summit of the Sierra Blanca 
group. On the morning of August 28th the party, with a 
pack-mule to transport the large theodolite, followed up a 
long spur which juts out to the south. They found no dif- 
ficulty in riding to timber line, which is here about 12,000 
feet above sea level. At this point they were compelled to 
leave the animals, and, distributing the instruments among 
the different members of the party, proceeded on foot up the 
loose, rocky slope to the first outstanding point, from which 
a view could be obtained of the main peak of the range. 
Although this first point is only 600 feet lower than the 
main summit, yet the most arduous portion of the task was 
to come. The main summit is about 2 miles north of the 
first point, in a straight line, and connected with it by a very 
sharp-toothed, zigzag ridge, over which it is most difficult to 
travel, on account of the very loose rocks and the constant 
fear of being precipitated down on either side several hun- 
dred feet into the amphitheatres below. After some two 
hours of this difficult climbing they came to the base of the 
main point, which, though very steep, was soon ascended, 
and at 11 o’clock a.m. they found themselves on the very 
summit. From this point one of the most magnificent views 
in all Colorado was spread out before them. The greater 
portion of Colorado and New Mexico was embraced in this 
field of vision. This point is the highest in the Sierra 
Blanca group, and, so far as is known at the present time, 
is the highest in Colorado. The elevation of this point was 
determined by Mr. Wilson in the following manner : — First, 
by a mean of eight barometric readings, taken synchronously 
with those at Fort Garland, which gave a difference between 
the two points of 6466 feet ; secondly, by fore and back 
angles of elevation and depression, which gave a difference 
of 6468 feet. The elevation at the fort was determined by 
a series of barometric readings, which, when compared with 
the Signal Service barometer at Colorado Springs, gave it an 
elevation of 7 997 feet, making the Blanca Peak 14,464 feet 
above the sea level. This peak may be regarded, therefore, 
as the highest, or at least next to the highest, yet known in 
the United States. A comparison with some of the first- 
class peaks in Colorado will show the relative height : — ■ 
