On the method of measuring Heights hy Boiling Water. 181 



I then proceeded to take the observations of Las Juntas 

 and Sombreros, and calculating the exponent anew. 

 B. in Las Juntas 21 9 B. W. 74-60 



in Sombreros 19 6*05 72*40 



Differences 2 2*95 2'2 



26-95 : 2°-2 : : 12 ^; ^ ^'^ = 0''-979 Reaumur for 12 lines of 

 26"95 



the barometer. 



B. in Paisbamba 20 9-1. B. W. 73°-50 



in Tambores 18 11'6. 71 '75 



Differences 1 9*5 1°'75 



1-9-5 = 211-5 : l°-75 : : 12 ^^^^ = 0°-976 of Reaumur 



for 12 lines of barometer. 



The mean of the six quotients is 0-974, which may be as- 

 sumed as the exact exponent of 12 lines of the barometer. 



Given then the heat of boiling water in any place to find the 

 corresponding elevation of the barometer ^ and consequently its 

 height above the sea. 



As 0°-974: 12 lines, so is the difference of the heat of 

 B. W. To ascertain at Popayan the number of inches, lines, 

 &c. of the barometer. Ex. in Tambores, B. W. 71°-15, to 

 find the corresponding height of the barometer. 

 B. W. in Popayan 75°-65 

 in Tambores 71 '75 



3 -90 



3-9 y 12 

 0-974 : 12 : : -—^ — = 481-05 = 4-0-05. 

 974 



As Tambores is above Popayan, deduct this quantity from 



the height of the barometer in that city. 



Bar. in Popayan 22 11 -20 



Deduct 4 00-05 



Remain 18 11 -15 ht. of bar. in Tambores. 



Barometrical height observed 18 11-60 

 Do. by calculation of B.W. 18 1M5 



Difference 45 



a result as exact as can be desired. 



Upon this principle I calculated the elevation of the fol- 

 lowing 11 places: 



