﻿16 EQUIPMENT AND WORK OF AN AERO-PHYSICAL OBSERVATORY. 



Elster and Geitels Potential-vapor Values. 



Mean. 



dv 

 dn 



V 



a? 



1 



1 



6 observations 



6 " 



502 

 430 

 400 

 318 

 252 

 137 

 184 

 148 

 112 

 115 

 118 

 121 



54 



59 



141 



150 



257 



91 



120 



169 



158 



135 



76 



54 



1.4 

 1.7 

 2.3 

 3.5 

 4.4 

 5.5 

 6.4 

 7.5 

 8.4 

 9.4 

 10.7 

 13.8 



—11.8 

 —10 1 



14 " 



— 64 



15 *' 



8 



23 " 



4 7 



8 " .... 



10 



11 " 



9 9 



16 " 



12 6 



13 " 



15 1 



14 " 



16 8 



7 " 



19 4 



5 " 



21 8 







We can get at the relation of the potential values and the quantity of 

 vapor present in the following way : 



The weight of aqueous vapor in a cubic metre of saturated air is the 

 product of the weight of a cubic metre of dry air at 0° 0, pressure 

 760 mm. and the density of the aqueous vapor, and the pressure of 

 aqueous vapor in saturated air, all divided by 1 plus the temperature 

 correction. 



^^ ^ where a = 1.29278 kg, d = 0.6221, and a = 0.003667 



^^ 1 + a ^ 760 

 the weight of vapor then is 0.622 



1.6. 



1.9. 



2.5. 



3.7. 



4.6. 



5.6. 



6.5. 



7.6. 



8.4. 



9.4. 

 10.6. 

 13.5. 



1.2927: 



1 + .003667 t 



Observed v. 

 502 



Estimate 

 469 



430 



442 



400 



364 



318 



268 



252 



224 



137 



189 



184 



166 



148 



145 



112 



133 



115 



119 



118 



107 



121 



85 



