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LXII. Intelligence and Miscellaneous Articles, 



To the Editors of the Philosophical Magazine. 

 Gentlemen-, 

 A LLOW me to call your attention to the fact that in January 

 -^- 1897 Messrs. Stroud and S. B. Henderson published in 

 No. 260 of this Journal a paper entitled " A Satisfactory Method 

 of Measuring Electrolytic Conductivity by means of Continuous 

 Currents," in which several authors are quoted who have em- 

 ployed methods similar to that described in the papeV above 

 mentioned. 



Messrs. Stroud and Henderson must have forgotten or over- 

 looked my statement in Wiedemann's Annalen, vol. xxiii. pages 

 482-490, in which not a similar, but in fact the very same method 

 is described by me. 



The fig. 1 on page 21 of the paper in your journal is quite the 

 same as the fig. on page 482 in my statement. I have employed 

 for the equal resistance only 20 S. E., whereas Messrs. Stroud and 

 Henderson have used 1000 ohms. 



Certainly I was aware of the advantage of a higher degree of 

 resistance, and the reason for the little power I used was, as I 

 expressly mentioned on page 483, the fact that I had no greater 

 resistance at my disposal. 



I remam, 



Tours faithfully, 



F. Neesen. 



THE HEATS OF VAPORIZATION OF LIQUIDS. 

 To the Editors of the Philosophical Magazine. 



GrENTLEMEtf, 



Mr. Griffiths has kindly drawn my attention to a slight error 

 on page 298 of my paper in your April issue, viz. : that the mea- 

 surements by himself and Miss Marshall of the latent heat of 

 benzene extended up to 50° C, instead of 40° as I inadvertently 

 stated. 



I may also take this opportunity of noting that on page 290 of 

 the paper on " The Variation of the Dissociation Coefficient " the 

 last three equations are reduced to the ordinary form by expressing 

 the gas-constant E in gram-calories, instead of in the work-units 

 used previously. This explains the disappearance of J from the 

 previous equation, and should have been stated at the time. 

 I am, Grentlemen, 



Your obedient servant, 



S. E. MlLNER. 



University College, Bristol, 

 May 1, 1897. 



