596 TABLES 631-640.— DENSITIES AND HUMIDITIES OF 



MOIST AIR 196 



TABLE 631.— RELATIVE DENSITY OF MOIST AIR FOR DIFFERENT 

 PRESSURES AND HUMIDITIES 



p ar t 1. — Values of ^r , from h — 1 to h = 9, for the computation of different values 

 760 

 of the ratio of actual to normal barometric pressure 



This gives the density of moist air at pressure h in terms of the same air at normal at- 

 mosphere pressure. When air contains moisture, as is usually the case with the atmos- 

 sphere, we have the following equation for pressure term : h = B — 0.378/), where p is 

 the vapor pressure, and B the corrected barometric pressure. When the necessary psy- 

 chrometric observations are made the values of p may be taken from Table 640 and then 

 0.378p from Table 632, or the dew point may be found and the value of 0.378/> taken from 

 Table 632. 



h 



760 



.0013158 

 .0026316 

 .0039474 



.0052632 

 .0065789 

 .0078947 



.0092105 

 .0105263 

 .0118421 



Examples of use of the table 



To find the value of -=™ when h = 754.3 



h = 700 gives .92105 

 50 " .065789 

 4 " .005263 

 .3 " .000395 



754.3 



.992497 



h , 



To find the value of =7^ when h = 5./ 



760 iW 



h = 5 gives .0065789 

 .7 " .0009210 

 .03 " .0000395 



5.73 .0075394 



Part 2. — Values of the logarithms of — s for values of h between 80 and 800 



760 



Values from 8 to 80 may be got by subtracting 1 from the characteristic, and from 0.8 to 

 8 by subtracting 2 from the characteristic, and sc on. 



Values of log 



760 



80 1.02228 

 90 .07343 



100 1.11919 

 110 .16058 

 .19837 

 .23313 

 .26531 



120 

 130 

 140 



150 1.29528 

 160 .32331 

 .34964 

 .37446 

 .39794 



170 

 180 

 190 



200 1.42022 

 210 .44141 

 .46161 

 .48091 

 .49940 



220 

 230 

 240 



1.02767 

 .07823 



1.12351 



.16451 

 .20197 

 .23646 

 .26841 



1.29816 

 .32601 

 .35218 

 .37686 

 .40022 



1.42238 

 .44347 

 .46358 

 .48280 

 .50120 



1.03300 1.03826 



.08297 .08767 



1.12779 1.13202 



.16840 .17226 



.20555 .20909 



.23976 .24304 



.27147 .27452 



T.30103 T.30388 



.32870 .33137 



.35471 .35723 



.37926 .38164 



.40249 .40474 



T.42454 1.42668 



.44552 .44757 



.46554 .46749 



.48467 .48654 



.50300 .50479 



1.04347 

 .09231 



1. 13622 

 .17609 

 .21261 

 .24629 

 .27755 



1.30671 

 .33403 

 .35974 

 .38400 

 .40699 



1.42882 

 .44960 

 .46943 

 .48840 

 .50658 



1.04861 

 .09691 



1.05368 1.05871 

 .10146 .10596 



1.06367 1.06858 

 .11041 .11482 



1.14038 1.14449 1.14857 1.15261' 1.15661 



.17988 .18364 .18737 .19107 .19473 



.21611 .21956 .22299 .22640 .22978 



.24952 .25273 .25591 .25907 .26220 



.28055 .28354 .28650 .28945 .29237 



T.30952 T.31231 1.31509 1.31784 1.32058 



.33667 .33929 .34190 .34450 .34707 



.36222 .36470 .36716 .36961 .37204 



.38636 .38870 .39128 .39334 .39565 



.40922 .41144 .41365 .41585 .41804 



1.43094 

 .45162 

 .47137 

 .49025 

 .50835 



1.43305 

 .45364 

 .47329 

 .49210 

 .51012 



1.43516 

 .45565 

 .47521 

 .49393 

 .51188 



1.43725 1.43933 

 .45764 .45963 



.47712 

 .49576 

 .51364 



.47902 

 .49758 

 .51539 



196 The tables on densities and humidities have been adapted from the sixth edition of the Smithsonian 

 Meteorological Tables, which see for more extensive data. 



(continued) 



SMITHSONIAN PHYSICAL TABLES 



