Barus — Ionization of Water and Phosphorus Nuclei, 21.7 



Art. XXII. — The Ionization of Water and of Phosphorus 

 Nuclei. {Supplementary paper) ; by C. B Anus. 



1. In the preceding paper,* I gave a revision of my views 

 of the motion of the nucleus, showing that they admitted of 

 an extension sufficient to include the exceptional and unex- 

 pected behavior of the water nucleus in the electric field, 

 within the limits of potential used in my experiments. 



1,^1 have since pursued the question into further detail and 

 completed the computation for water nuclei and for phos- 

 phorus, so far as the data now admit. In equation (3) § 14 of 

 the paper cited, I will put K = k-\r UE/ir^—r^, and proceed to 

 find 



1 __ e~ a = 1 — e ~ "377*2 fo +r 1 )/V 



for a series of values of IT, as follows : 



JT=-001 1 — e -a ='013 K= -2 1— e~ a = *925 



•01 -121 -4 '994 



•05 '476 -8 1-000 



•1 -736 1-0 1-000 



This curve may be constructed in a chart in which iT is the 

 abscissa and 1 — e~ a the ordinate. In the exponent, 2^ 2 =2'10 cm , 

 2 r — -64 cm , I = 50 cm , V— 2 lit/min. Meantime, one may note 

 that if iTand I vary reciprocally, the result remains unchanged. 

 An inspection of the curve shows that the marked flexure 

 occurs at about E = '2. 



Now if the results for water nuclei (1. c, chart fig. 4) be 

 compared with this curve, the two cases are seen to be quite 

 similar and the marked flexure of the former occurs at about 

 E — 10 volts as the electromotive force of the condenser. 

 Since for water nuclei the specific velocity in the non-electric 

 field is negligible, It — and K= UE/^—r^. Hence if for 

 coordination the points of marked flexure be regarded identi- 

 cal, K— *2, corresponds to E = 10 volts, roughly, and thus 



*2 V '73 



U= — £ = -0146 cm. /sec. 



10 ' 



2. If the velocity Z7of the nucleus be computed from the 

 estimated radius R and the viscosity of the air, as in § 5, the 

 data are, since RU— *125xl0" 6 in a field of volt/cm. 



* This Journal (4), vol. xv, pp. 105-120, 1903. Cf . § 14. The notation is 

 the same in both papers : E denoting the potential, C the effective capacity 

 of the condenser ; n the number of nuclei per cub. cm., e the charge of 

 each, k their absorption velocity, U their combined ionic velocity ; r refers 

 to the radii, I to the length of the condenser and t is the current time. 



