Use of the Aneroid in Contour Map piny 



117 



aneroid readings taken by each crew in moving, readings were 

 made by the men who did the packing when going back and 

 forth between the two camp sites. Each set of figures consisted 

 of the date and the time at which the readings were taken at 

 each camp site. 



DATA TAKEN IN ORDER TO ESTABLISH A NEW BENCH MARK 

 WHEN WORKING FROM A CAMP. 



After the necessary corrections had been made for the 

 variation in atmospheric pressure the following table was ob- 

 tained, which shows the relative elevation of camp No. 4, above 

 camp No. 3. 



I Set No. 



Difference 

 in elevation 



An average of the eleven sets gave 440 feet as the relative 

 difference in elevation between the two camps, making the abso- 

 lute elevation of camp No. 4, 1893 feet. Two sets of readings 

 were also taken between camp No. 4 and the United States Geo- 

 logical Survey bench mark. 3018 feet, from which the elevation 



o J 



