lxX INTRODUCTION. 



Table 96. Term for humidity; auxiliary to Table 95. 



TT h B - 0.378 e 



Table 97. Humidity and pressure term. = 



29.921 39.921 



table 96 gives values of 0.378 e to three decimal places as an aid to the 

 use of Table 97. The argument is the dew-point given for every degree 

 from — 6o° F. to + 140 F. The second column gives the corresponding values 

 of the vapor pressure (e) derived from Tables 69 and 70. 



table 97 gives values and logarithms of = '- for values 



29.921 29.921 



of h extending from 10.0 to 31.7 inches. The logarithms are given to five 

 significant figures and the corresponding numbers to four decimals. 



Example : 



The air temperature is 68° F., the pressure is 29.36 inches and the dew- 

 point 51 F. Find the logarithm of the density. 

 Table 95, for / = 68° F., gives 7.08085 - 10 



Table 96, for dew-point 51 , gives 0.378 e = 0.142 inch, 

 Table 97, for h = B - 0.378 e = 29.36 - 0.14 = 29.22, 



gives 9-9894I - 10 



30 



Logarithm of density = 7.07056 — 10 



metric measures. 

 Table 98. Temperature term. 



This table gives values and logarithms of the expression 

 * 0.00129305 



dt - 76 ° 1 + 0.00367 t 



for values of / extending from — 34 C. to + 69 C. The tabular values are 

 given to five significant figures. 



Table 99. Term for humidity ; auxiliary to Table 100. 



tt 7 h B - 0.378 e 



Table 1 00. Humidity and pressure terms, —r- = 



760 760 



Table 99 gives the values of 0.378 e to hundredths of a millimeter for 

 dew-points extending from — 50 C. to + 6o° C. Above — 25 C. the interval 

 is one degree. The values of the vapor pressure, e, corresponding to these 

 dew-points, given in the second column, are taken from tables 71 and 72. 



Table 100 gives values and logarithms of — — = ■—■ — for 



760 760 



values of h extending from 300 to 799 mm. The atmospheric pressure B is 

 the barometer reading corrected for gravity and 0.378 e is the term for 



