on the Emanation of Phosphorus. 333 



Table II. — Radial currents in the condenser. Phosphorus ionizer at different 

 temperatures. Example of method. 



Time, t 



7xl0 2 



dV/dt 



(mean) 5 



ds/dt 



6 



7 m 30 s 



70 



* lit 

 mm. 







15-3° 



9 30 



125 











12 30 



205 











s 







163 



s 



12-r- 



mm. 





15 







166 







30 







169 







45 







172 







13 m 30 s 



280 



no 1^ 



min. 







15-3° 



15 30 



450 











17 30 



610 











s 







163 



27-^ 

 mm. 





15 







170 







30 







176 







45 







183 







II. Discussion. — The data of these tables might be con- 

 structed without further reduction in a graph where the 

 abscissas are temperatures and the ordinates, ds/dt, propor- 

 tional to the radial currents. Two curves are suggested, one 

 for the high, and another for the low velocity, dV/dt ; but in 

 view of the slightly different values of d V/dt implied in 

 each, it is better to reduce to two volume standands ; dV/dt 

 = '45 liter/min. and l'OO liter/min. were selected as most 

 nearly coincident with the observations as a whole. The reduc- 

 tion was made compatibly with the results of my earlier paper 

 (1. a), linearly from two values of d V/dt and ds/dt at each 

 temperature. This linear relation is again incidentally shown 

 in figure 5 at about 19°. The slopes of these lines vary with 

 temperature. 



If Q be the charge, sthe deflection, C the effective capacity, 

 E the potential difference, A the factor of the electrometer, 

 Q= CAs i i= dQjdt— CA'ds/dt, where i is the radial cur- 

 rent. Thus i/Q = (ds/dt)/s. 



For the initial currents, as alone measured in this paper, 

 one may always assume the simple exponential relation 

 Q = Q e~ x ^— tp \ or ,§ = ^e - ^ - ^, where the subscripts zero 

 refer to the initial charges, deflections, temperatures, etc. 

 Hence, iJQ — (ds/dt) /s = — x, is an appropriate variable 

 for comparing the data. This may also be computed as 



