WILSON. I PRIMARY TRIANGULATION OF COLORADO. 279 



snow and rain came down alternately until the mountains were covered 

 to a dex)th of a foot and a half with snow while the plains were converted 

 into vast mud-holes. Finally, on the morning of the 19th, the storm 

 broke and we were soon on our way up the mountain. Breaking our 

 way through the fresh snow we succeeded in reaching the summit, where 

 we found the snow nearly two feet deep. Completing our observations 

 and sketches as soon as possible, nearly freezing in the mean time, we 

 soon descended to our camp, glad to be ready once more to resume our 

 march, for this delay had nearly entirely exhausted our supply of pro- 

 visions ; in fact, we had but one day's supply left and were about 100 

 miles from our main camp. 



Late at night on the second day we reo.ched the foot of Lone Cone, 

 but not finding our main camp, were compelled to camp, notwithstanding 

 the fact, which weighed heavily on our minds, that we had eaten our 

 last morsel of provisions at five o'clock the previous morning. 



Arousing ourselves at break of day the following morning and finding 

 the weather looking unsettled, I determined to ascend the peak before 

 spending any more time in search of camp, fearing that a storm might 

 again delay us. After some three hours of hard climbing we reached 

 the summit, and I succeeded in getting a good set of observations. 

 After completing my work I scanned the horizon with my field-glasses 

 for our main camp, which I finally discovered about seven mileseastward. 

 Eeturning to where I had left the animals we soon packed up, and 

 wending our way through down timber, bog-holes, and snow, we ar- 

 rived at our camp about 4 p. m., pretty well worn and ready for a 

 " square " meal, which we had not enjoyed for two days. 



The next morning found us on our way to Uncompahgre agency, 

 where we found some fresh supplies and mail awaiting our arrival. 



From Uncompahgre agency we followed down the river nearly to its 

 junction with the Gunnison, then turning slightly to the east crossed 

 the Gunnison, taking an old Indian trail which we had been informed 

 by the Indians would lead us to White Eiver, making a station on 

 North Mam Peak on our way ; we arrived at the agency on White Eiver 

 September 30. 



After making two stations in this vicinity, which completed our sea- 

 son's work, we started for Eawlin^s Springs, where we arrived on the 

 11th of October, having occupied eleven geodetic stations, which com- 

 pleted the triangulation of Colorado. 



From Eawlins the mules and outfit were all shipped by rail to Chey- 

 enne, where they were quartered for the winter, and the party imme- 

 diately proceeded directly to Washington. 



PEIMAEY TEIANGULATION. 



When the survey of Colorado was commenced, in the spring of 1873, 

 by the United States Geological and Geographical Survey of the Terri- 

 tories, it was found necessary to inaugurate a system of primary tri- 

 angulation, in order to locate a number of points with a considerable 

 degree of accuracy, upon which the topographical work might be based. 



The first important step was to find a suitable location for the accu- 

 rate measurement of a base-line. This first step is all-important, as the 

 future work depends entirely upon the accurate measurement of the 

 base. 



After reconnoiteriug the country in the vicinity of Denver, Mr. Gard- 

 ner selected a spot just east of the city, where a "tangent" of the Kan- 



