C. Barns — Ionization of Water Nuclei. 115 



The currents are given in the chart and marked 4. They 

 show that above 10 volts the currents are practically constant, 

 remembering that any change in T^due to water pressure, etc., 

 will convey the nuclei more rapidly into the condenser, and 

 from their exceedingly rapid decay at the outset, the currents 

 will necessarily be variable. Below 10 volts the current 

 decreases with the potential but remains quite appreciable even 

 when the potential is zero with the absence of charge in the 

 condenser. The two observations made for the negative charge 

 indicate similar relations, when taken in connection with the 

 preceding results. 



The average number of nuclei in those cases where positive 

 and negative charges were observed are found to be 



at 81 volts rc = l-4 X 10 6 

 at 20 volts n = 1'6 X 10 6 ~ 



results slightly larger than the preceding, again due to further 

 enlargement of the holes of the jet, whereby fresher nuclei are 

 put into the condenser. 



The table states that the most advanced corona obtainable 

 did not exceed 'No. 8 or 9 of my series,* throughout the whole 

 of the work. It makes little difference whether the corona is 

 taken instantly or a few minutes after the jet is shut off. The 

 number of nuclei, therefore, is constant throughout the experi- 

 ments. 



Summary and inferences. 



11. Charge and Conduction. — The data have shown that 

 positive as well as negative charges are dissipated by water 

 nuclei, immediately after they have been produced, and that 

 the ionization, if it may be so called, is quite of the order of 

 that of phosphorus. After being stored but a few minutes, 

 the nucleation loses all but a few per cent of this property of 

 conduction, behaving in this respect again like phosphorus 

 nuclei. The number of nuclei does not appreciably vary in 

 the same time. The character of the ionization (whether posi- 

 tive or negative nuclei are in excess) remains intact, so long as 

 it can be observed. Hence the large initial and the eventual 

 very small conduction (a few per cent of the original value) 

 may be regarded as two successive phases of a single continuous 

 phenomenon, either of charge or ionization or conduction. It 

 seems to me therefore that it is not necessary to distinguish the 

 initial charges from the initial ionization. The experiment as 

 a whole shows an attenuation of the Lenard effect, continuously, 

 through infinite time. One is at liberty to refer the conduc- 

 tion either to charged nuclei or to ionized nuclei, unless some 

 *Phil. Mag. (6), iii, p. 80-91, 1902. 



