72 



A CONTINUOUS RECORD OF ATMOSPHERIC NUCLEATION. 



For the pressure diflference 6p = 22 cm. which will occur below, 



w = 

 For (5/? = 8.5 cm. 



4.2X 10 



5-5X10- 



6.7X10-" 



2.8X10-" 



;;;= 2.1X10-* 2.6X10" 



The effect of temperatvu'e on latent heat is not considered, since the data are 

 not fully known. Its effect may be i to 2 per cent. More important is the value 

 to be taken for the heat ratio ;/= 1.41. 



15. Resulting equations applied. — From what has been stated, it follows 

 that the first quantity to be found is the initial nucleation, n^, i. e., the nucleation 

 which obtains when z — Z. This depends on incidental conditions, such as the 

 intensity of the ionizer, the first corona seen (Z), etc., and is therefore quite 

 arbitrary. In table i, for instance, n^ = n^. Hence 



«. = w„io<---""«^(i-5/5-) (i-S/50 (i-S/5g) .. .(i-5Ai,..,), 



which wiU be abbreviated 



w, = «oio'=-*>''"^'' 77'(i-5/50. 



This equation affords in the first place a means of computing 5. For in 



the region of nonnal coronas n is given by the apertures of the coronas. If, for 



brevity, r,=nJio''°''\ 



r^+Jr^^, = (i - S/sl^ ,) (i - S/si), 



from which 5 is determinable in terms of pairs of values of r and s; or 5 may 

 be even more simply found from two successive normal coronas. The follow- 

 ing table shows the values found for the two series in table i . 



TABLE 7.— VALUES OF 5 FROM rz+,/r,_.= i -5 {i/s^l, + i/st)-^S'/s^l^sl. 



