424 C. Barns— Decay of Ionized Nuclei. 



cubic cm. It is not possible, however, from results of the char- 

 acter of the present, to discriminate sharply between c and b, 

 and the endeavor will have to be made to select the best values 

 from inspection. 



In these series the constants obtainable for different inter- 

 vals of time separately for each series would be as follows : 



Series 



1 



1 



2 



2 



3 



3 



4 



10 e b 



2-4 



2-9 



•82 



•88 



•61 



•56 



1-1 



10 3 c 



— 18 



— 20 



45 



32 



41 



40 



39 



The mean data of series 2 to 4 would then be b = '000000,79, 

 g — *039. There is a curious consistency in the constants 

 separately determined, even when the compensating values of 

 b and c are of different signs, as for instance in series 1. The 

 reason is not apparent. The constants will necessarily be 

 correct at three values of I, but the computed values of n are 

 no better as a whole than will be the case if the first set of 

 constants of series 2 for instance were used. In fact the con- 

 stants b may be arbitrarily put at a reasonable estimate* 

 b = -000,001 with c — - 0356 and a fair reproduction of the 

 observation is obtained. This is shown in the charts where 

 these computed values (b = 10^ 6 ) are incorporated. ' Close 

 inspection, however, shows that in all cases the fall of computed 

 curves, while not quite rapid enough at t — t <C 10, is somewhat 

 too rapid for higher time intervals. Thus b should be less 

 than 10~ 6 and c greater than "035, to be adapted to the present 

 results. 



The question finally arises whether any systematic error 

 in the standardization of coronas and hence in the values of n, 

 could have produced an effect equivalent to the occurrence of 

 a constant c. Suppose that — dn/dt—brC for the true nuclea- 

 tion, and that N=A + Bn as the result of systematic errors 

 of standardization. Then — dN / 'dt-b' 'JS "+<?' 'N+d ', an equa- 

 tion broader in form than the one accepted. The constants 

 d' and c' both vanish with A, the former more rapidly. 

 Hence, the possible introduction of c through the method of 

 standardization is not excluded however how improbable, since 

 the equation is conditioned by the occurrence of A. 



8. Conclusion. — If the rate of decay of ionized nuclei be 

 written bri 2 , the coefficient b as found by the fog chamber 

 increases as n decreases and may reach tenfold the order of the 

 usual electrical value of the order of 5 = 10"\ The endeavor to 

 explain this by supposing that but 1/m of all the ions are 

 caught and dn/dt— —mb?i, is not satisfactory. 



*Townsend, McClung, Langevin. find & = 1*1 x 10 — 6 about, using the usual 

 electrical method. See Rutherford's Radioactivity, pp. 41, 42, 1905. 



