678 GEOLOGICAL SURVEY OF THE TEEEITOEIES. 



HYPSOMETRICAL. 



Tlie most important elevations in the following lists were determined 

 with the mercurial barometer, until August 22, when the last barom- 

 eter-tube was broken. Elevations of minor importance, and, after 

 August 22, all elevations, except those measured trigonometrically, were 

 measured by aneroids. While there was a cistern barometer in the party, 

 the aneroids were compared daily; and alter this barometer was broken, 

 corrections were obtained for the aneroids whenever possible, and in 

 every case these showed a remarkably good performance on the part of 

 these instruments. 



A part of the elevations submitted below were measured by vertical 

 angles taken with the gradienter. The vertical circle of this instrument 

 is four inches in diameter, and reads, by a vernier, to single minutes. 

 The correction for refraction was determined by a series of fore and 

 back sights between mountain-peaks to be ai^proximately one-sixth of 

 the curvature, and this correction has been applied to obtain these 

 lesults. 



Barometric observations taken in Denver by the officers of the United 

 States Signal-Service Bureau, during the summer and autumn, were 

 placed at our disposal for use as base observation s. At Fairplay, South 

 Park, elevation 10^048 feet, barometric observations were takeu for us 

 three times a day from July 19 to October 1, and at the Moose Mine, 

 near the summit of Mount Lincoln, elevation 14,188 feet, observations 

 have been taken since July 20. 



To the Denver observations as a base have been referred all work at 

 elevations below 8,000 feet ; to Fairplay, all work between 8,000 feet 

 and the timber-line, that is, about 11,600 feet ; and to Mount Lincoln, 

 all above the timber-line. 



In the following lists a refers to an aneroid measurement, tto ^ trig- 

 onometrical determination. In other cases the measurement was made 

 by a mercurial barometer. The elevation of Denver above sea-level has 

 been assumed at 5,197, the level of the track of the Denver Pacific Rail- 

 road. This makes the elevation of the barometer in the United States 

 Signal-Service office, 5,245 feet. 



LIST OF ELEVATIONS 



Along the line of the Denver and Bio Grande Railroad from Denver to Colorado Springs 

 at the east foot of the mountains. 



Miles. Elevation, 

 feet. 



Denver 5,197 



Littleton • 10 5,362 



Acequia 17 5,530 



Plum. 25 5,835 



Citadel 31 6,123 



Douglas 35 6,325 



Larkspur 43 6, 666 



GreeDlaucl 47 6,928 



Divide 52 7,209 



Henrv's ■ 56 6,984 



Berst's 58 6,812 



Husted 62 6,600 



Monumeut 67 6,355 



Colorado Springs 76 5,9S4 



TOWNS, ETC. 



Colorado City 6,049 



Colorado Springs, railroad levels 5, 984 



Manitou a 6, 357 



