318 APPENDIX A 



mated mean error of 30 feet. The result of this is a mean error of 35 feet 

 in Coropuna's elevation above mean sea level. 



The latitude is 15° 31' 00" S. ; the longitude is 72° 42' 40" W. of Green- 

 wich, the checking of these two determinations giving a result unexpectedly 

 close. 



On November 11th azimuth and latitude observations were taken at 

 Chuquibamba and two days later we arrived at Aplao in the bottom of the 

 splendid Majes Valley. In the northern part of this valley I was prevented 

 from doing any plane-table work in the afternoons of four successive days. 

 A strong gale set in each noon raising a regular sandstorm, that made 

 seeing almost impossible, and blowing with such a velocity that it was 

 impossible to set up the plane-table. 



From Hacienda Cantas to Camana we had to pass the western desert 

 for a distance of 45 miles. We were told that on the entire distance there 

 was only one camping place. This was at Jaguey de Majes, where there 

 was a brook with just enough water for the animals but no fodder. Thus 

 we faced the necessity of carrying water for ten men and fodder for 14 

 animals in excess of the usual cargo; and we were unable to foretell how 

 many days the topography over the hot desert would require. 



Although plane-table work in the desert was impossible at all except in 

 the earliest and latest hours of the day, we made regular progress. We 

 camped three nights at Jaguey and arrived on the fourth day at Las 

 Lomas. 



The next morning, on November 23rd, at an elevation of 2178 feet near 

 the crest of the Coast Eange, we were repaid for two months of laborious 

 work by a glorious view of the Pacific Ocean and of the city of Camana with 

 her olive gardens in the midst of the desert sand. 



The next day I observed latitude and azimuth at Camana and in the 

 night my companion and assistant Mr. Watkins and I returned across the 

 desert to the railroad at Vitor. 



Conclusions 



The planned methods were followed very closely. In two cases only 

 the plane-table had to be oriented by the magnetic needle, the backsights 

 not being obtainable because of the impossibility of locating the last sta- 

 tion, passing Indians having removed the signals. 



In one case only the distance between two stations had to be deter- 

 mined by graphic triangulation exclusively, the base signals having been 

 destroyed. Otherwise graphic triangulation was used as a check on 

 distances. 



Vertical angles were always measured in both directions with the 

 exception of the above-mentioned eases. 



Observations for azimuth were always taken to the sun before and 



