430 Mr. J. Larmor on the Molecular 



We have, then, for the condensing sheet, 



a Airt 



where Y = 1 volt, 



= 10 8 -^-(3 x 10 10 ) electrostatic C. G. S. units. 

 Therefore 



g.lO^d-^s.io'.^ 



therefore 



-2, 1 ia-16 



ttrV^.io 



If now we write for £ the value found above, *3 x 10"" 8 , 

 and put t' and d equal to each other, both being molecular 

 distances of the same kind, we obtain for either the value 



4 _ 8 



jg x 10 centimetres, 



which is very exactly of the same order as the value for 

 molecular intervals obtained already from the other con- 

 siderations. 



On looking through this calculation it will be seen that 

 quantities which we have designated as of the same order of 

 magnitude do not differ nearly so much as in the ratio ten 

 to one. 



7. The two estimates of molecular distance which have thus 

 been found on independent considerations connected with 

 galvanic polarization therefore agree within very close limits; 

 and they come very close to the third value determined by Helm- 

 holtz on the same theory of galvanic polarization, viz. 1 x 10~ £ 

 centim. ; and they are also just below the superior limit as- 

 signed by Sir W. Thomson to molecular intervals from various 

 considerations connected with different physical phenomena, 



viz. 10"" 8 centim., his inferior limit being ^ x 10~ 8 centim. 



Sir W. Thomson's different arguments lead to the following 

 superior and inferior limits of the average distance of mole- 

 cules from one another in solid and liquid substances : — 



