56 



VAPOR NUCLEI AND IONS. 



From these the value of p t appears as 



p 3 +(Pz- n).v/V 



7 Pi c/k = 



p^k-c)/k + (p- i: ){k-c)/k^ I -njpjc/k. v /v 



where n x \p x occurring with the factor v/V may be neglected Further- 

 more 



8 (p 2 - tc) - (p - n) &-c)/k (p 1 -r: 1 ) c / k ; p' 2 = p 1 (**)/* p t c/k 



where n t (respectively n =o.io, 0.24, 0.51 in comparison with p t = 45.6, 

 52.2, 59.3) may again be neglected. 



The results of this computation are given in table 18 and fig. 276. 



Table 18 also contains the value of dp observed as p-p 3 and computed 

 as p-p 2 , the latter being the correct value. This table of corrections 

 will not apply below the limits of computation, since it x now becomes 

 appreciable in comparison with p x \ but above p-p3 = i$ cm., a table may 

 be constructed from which dp=p-p 2 may be taken at once. In this 

 way the following data will be corrected Since the main data for col- 

 loidal nuclei lie between p-p 3 = 2$ cm. and 32 cm., the correction will 

 lie between -4 cm. and -6 cm. 



Table 18, corresponding to table 17 for saturated moist air in the fog chamber. Tem- 

 perature 20 ; vapor pressure 1.7 cm.; p = j6; v/V =0.064. 



* Observed as soon as possible at the fog chamber; nearly same later. 

 t Observed as soon as possible at the vacuum chamber; p\"= Pa nearly. 



Table 19. The results are for ir= 1.7 at 20 . 



