8 



A CONTINUOUS RECORD OF ATMOSPHERIC NUCLEATION. 



Table i contains the direct observations, time in minutes, and deflections, s, 

 of the electrometer in centimeters. dV/dt, denoting the volume of nucleated 

 air put into the condenser per minute, is here estimated. The charge of the 

 core is negative. 



Table 2 gives a summary of these results, among which may be mentioned 

 the following: The insulation is not above a = .oi and usually lower. It is not 

 exceeded when phosphorus nuclei have access merely by diffusion (VII), nor 

 on being blown in from a wide vessel (VIII), the charge vanishing on the way. 

 The leakage is not exceeded when a slow current of highly nucleated air stored 

 over water is passed through the condenser (V), and but slightly for the case 

 of a fast current of such nucleated air (VI) taken out of the receiver A in the 

 figure. 



By contrast, the excessive ionization (a = .2 .3), if the nucleation is at 

 once introduced into the condenser, is striking enough. Hence scarcely 3 per 

 cent, of the original ionization has survived after short storage in the receiver 

 in spite of the extreme density of nucleation which the coronas would cotem- 

 poraneously show. In fact, the ionization dies out almost at once in the con- 

 denser (X-XIV), even in the absence of water vapor. 



9. Further data. The experiments were now repeated as in table 3, with 

 the resume of results shown in table 4. These are substantially like the above. 

 With fresh phosphorus the residual ionization of the nuclei-bearing air after short 

 storage over water is but a few per cent, of the original ionization. It was sup- 

 posed that on drying the nucleated air over phosphorus pentoxide, before 

 passing it into the condenser, the original ionization might be in part regained, 

 but the table shows not a trace of this. 



TABLE 3. IONIZATION OF PHOSPHORUS NUCLEI. dV/dt = ABOUT 2 LIT./MIN. 



NEGATIVE CHARGE. 



