548 GEOLOGY OF THE BLACK HILLS. 



tions on Harney Peak were made shows that there was no local disturb- 

 ance east or west of a line joining Cheyenne and the center of the Black 

 Hills, and the deduced height of Harney can be considered as very near 

 the truth, not more than 50 feet in error, I think. 



The height of Terry, as deduced from barometrical observations on 

 August 20, and from a zenith distance from Harney, agree within 12 feet. 



The observations on Harney were all made on the highest point, which 

 "•ave us much trouble and risk of life and limb to reach. The mean of four 

 of Green's compensated aneroid barometers gave as the height of Harney 

 7,440 ieet. 



As my altitude of Harney is so widely different from that found by 

 Colonel Ludlow, in 1874, I give both observations and computations here 

 complete. 



The altitude of the railroad track at Cheyenne is, according to an 



elaborate investigation by Mr. James T. Gardner, 6,075.28 feet, and by 



measurements by Dr. McGilly cuddy and myself, with a theodolite, the 



cistern of the standard barometer in the signal office is 9.58 feet' above the 



rails- This gives for height of cistern above the sea-level 6,085.86 feet, 



exactly one geographical mile. 



Observations made on the summit of Harney Peak, July 25, 1875, lat. 43°-52' JV. 



Observer, H. P. Tuttle. 



o o 



Ex. th. = 59.5 

 = 60.5 



= 58.0 

 = 59.2 



Bar. 2123 



10.00 a. m. 

 10.30 

 10.45 

 11.00 



>enne standard 



in. 

 23.248 

 23.238 

 23.242 

 23.249 



Att. 

 = h' 



th. 



o 



= 63.6 

 = 64.9 

 = 61.6 

 = 65.6 



Means 



Reduced to Clie^ 

 Reduced to 32° 



23.244 



- .003 



- .073 



63.9 





23.168 





59.3 = V 



