384 M. W. Beetz on the Magnitude of Galvanic Polarization. 

 The following table is deduced from the above and from fonner 



observations : — 



Electromotive 

 Polarization. force. 



In iodine .... 3*59 3*36 f 



In bromine . . . 6*89 696 ^ 



In chlorine . . . 10"58 1010 



In hydrogen . . . 19*08 17*89 



In chlorine + hydrogen 28*83 27*99 



Consequently the law above expressed is true for all these substances. 



In a former memoir* I found that the polarization of a pla- 

 tinum plate in dilute sulphuric acid, in comparison to the force 

 of a Grove's battery, was as 21 : 32, hence its true value is 



24-4; 



later measurements gave a mean value equal to 



25-30, 



or six units greater than in hydrochloric acid. This difference 

 may probably be explained by the separation of the ^yater. 



The deviation of the polarization Pt(0)( = 24'4) from the elec- 

 tromotive force of this gas ( = 3*42) is, however, very great 

 indeed ; it cannot certainly be explained by the concentration of 

 the acid. I expected to find that the formation of ozone caused 

 this deviation, inasmuch as, according to its chemical and phy- 

 sical properties, ozone always deports itself as negative with 

 respect to chlorine. It is true that all attempts to generate a 

 sufficient force by converting oxygen into the allotropic condition 

 by means of an electric discharge were unsuccessful ; nevertheless 

 I do not relinquish the hypothesis, seeing that, according to this 

 method, only small traces of the allotropic oxygen could arrive at 

 the gas battery, the greatest part being consumed in the forma- 

 tion of ozone, or becoming converted into the usual condition. 

 The polarizing action of the allotropic oxygen, therefore, is limited 

 to the moment of its production ; and hence the polarization of 

 the positive electrode may sink in so quick a curve to the elec- 

 tromotive force Pt (0)t, whilst that of the negative electrode has 

 only to traverse the small fall Pt(H), perhaps only to the reprO' 

 duction of the original condition of the liquid. 



* Pogg. Ann. vol. Ixxviii. p. 3. 

 t Ibid. vol. Ixxix. p. 10. 



