Irreciprocal Conduction. 145 



Table IV. — Irreciprocitv with Platinum Electrodes 

 in KHO *. 





Point anode. 



Plate anode. 



Resistance of voltameter. Exp. 1... 



111-3 ohms. 



33'5 ohms. 



.., 2... 



120 „ 



32 



Polarization „ ,, 1... 



2-65 volts. 



2-12 volts. 



„ 2... 



2-65 „ 



2-16 „ 



Current through „ „ 1... 



•00265 ampere. 



•0178 ampere. 



o 



>5 >) )> >> **••« 



•00247 „ 



•0149 



c. Other Liquids. — No film was obtained with platinum 

 electrodes in the following liquids : — (l)Pure fuming HN0 3 ; 

 (2) a mixture of HN0 3 and H 2 S0 4 , the former being in 

 excess ; (3) strong HC1 ; (4) a mixture of HN0 3 and HC1 

 in equal parts. The film was obtained with strong H 2 S0 4 

 in which Cr0 3 had been dissolved, but no remarkable features 

 were noticed. 



5. Experiments on Soap and Sodium Benzoate. 



A piece of common white soap was cut in the form of a 

 cylinder 4 cm. long and 1 cm. diameter. It was protected 

 by a glass tube, and mounted so that platinum plates pressed 

 against its two ends. The resistance, as measured by Ohm's 

 method, showed a gradually increasing value, the battery being 

 kept, in circuit, from 1080 to 23,000 ohms, at which it re- 

 mained constant. The polarization was taken for various 

 times of charge, but showed but little variation. Measure- 

 ments of the resistance of the soap with a battery in its circuit 

 were also made by Kohlrausch's method, the results confirm- 

 ing those previously obtained by Ohm's method. With 

 solutions of soap the solid soap acids were separated out, but 

 there were no signs of any film-formation. 



In many respects a solution of sodium benzoate resembles 

 soap, for benzoic acid is but little soluble in water, hence it 

 was thought that an electrolytic deposit at the anode might 

 stop the current. This was found to be the case ; different 



* Further measurements are being made both with KHO and other 

 liquids by means of the method of Fucha, which with certain precautions 

 now appears to us to be the one best adapted. 



Plat. Mag. 8. ;>. Vol. 26. No. 159. Au<j. 1888. L 



