24 Meteorological Observations made in, Sf'c. 



which I have observed on comparing three together to amount 

 often to 1|°, and never to less than i°. 



I took the following method to obtain an exponent of the 

 value in feet of each degree of the diminished temperature of 

 boiling water. 



The elevation of Q.uito is, according to Boussingault, 9524 ; 

 and water boils at 1960.25 ; 212°-196°.25 = 15°.5.9524-r- 

 15.75 = 604 ft. 6. in. nearly. Neglecting the fraction as unim- 

 portant, I assumed 604 for the value of the degree, and began my 

 observation on the conical hill of Javirac, which backs the city, 

 and is calculated at 729 feet in height. Water boiled here by two 

 thermometers at 195°. Then 196°.25-^ 195 = 1.25, difference 

 of boiling water between the hill and the city ; and 1,25 X 604= 

 755 feet ; difference 26 feet. I next ascended the volcano of 

 Pichincha, and found at the foot of the crater B. W. 186°.212° — 

 186°=260x 604 = 15,730 feet; and adding 246 feet, the differ- 

 ence between this point and the summit, reckoned at 15,976. 

 There could be little error in the calculation. I next applied this 

 formula to the heights of several places calculated by Humboldt, 

 and where the heat of boiling water had been ascertained by 

 Caldas, 



Thus Bogota, height according to Humboldt - S694 ft. 

 B. W. according to Caldas 197°. 6 - - - 8712 



Difference - - - 18 

 Popayan, according to Humboldt - - , - 5823 



B. W. 202°.21 - - - - - - 5922 



Difference - - - 99 

 nboldt - - - 8572 

 B. W. 197°.6 8712 



Paste, according to Humboldt _ - _ 8572 



Difference - - - 140 ft. 



The differences here are in four points 27 feet, 18, 99, 140, 

 With respect to the hill of Javirac, commonly called U I Pane- 

 cillo, I suppose the measurement to have been made by the Ac- 

 ademicians. But their calculations generally differ from those of 

 Humboldt, as in the case of Quito ; the former giving 9371 feet, 

 the latter 9537 ; Pichincha 15,606 feet, Humboldt 15,976 ; Chim- 

 borazo 20,583, Humboldt 21,414. But even a difference of sites 



