128 



SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 51 



In which ft is a constant whose value depends on circumstances. 

 Knowing p and / we shall find the temperature z by formula (5) 

 of §i, namely 



e - 1 f\ 



-T~p)- 273 W 



T = T 1 - 



Applications 

 m = 3.441 4.0 



10 



Variation of temperature \ gg4 Q0 ^ Q0 ^ QO ^ 



per ioo m J 



Height for a variation of \ 1Qlm n7 , n 146m ^ 



i°C. J 



z = 



P 

 Pt> 



P 

 P 



P 

 Po 



1000 m 4000 ra 10000 r 



T = 273 m = 3.5 



0.88038 0.58259 0.21250 



To = 273 m = 5 



0.88094 0.59013 0.23681 



To =273 m = 10 



0.S816G 0.59841 0.26266 



20000' 



0.01233 



0.03106 



0.05609 



Dr. Julius Hann has published a series of observations on the 

 tension of aqueous vapor at different altitudes (see the Zeitschrift 

 der Oesterreichischen Gesellschaft fur Meteorologie, 1874, page 195). 

 In this case applying formula (8) we shall assume 



r = 20°, f - 10 mm , m = 10 and /? = 3 



The values of calculated for these constants are found in the 



/o 

 third line of the following table. 



Assuming T = constant = 273 and /? = 3 we find the values 

 written in the fourth line. The observed values are found in the 

 second horizontal line. 



