R12 



default of this knowledge we can therefore only say that probably 



J} 

 C will be such that ^' = 4w — - will become about b' = m^, in 



G 



which ni represents the volume of the molecules with their immediate 

 sphere of influence (see § 1) — in harmony with the theory of the 

 absorption of energy and transmission through the intermolecular 

 medium (cf. also § 1). 



If an analogous image is wanted: the old ballistic theory of 

 the rectilinear motion of the colliding molecules is in the same 

 relation to the modified theory, in which the temporary mutual 

 influencing of the molecules is considered which will take place at 

 every impact, or (what comes to the same thing) to the medium 

 tlieory — as the consideration of the effect of a ray of light, 

 after it has passed through a narrow aperture without taking the 

 inflection into account, so that only that part of the space behind 

 the aperture would be affected by the light which is in the direction 

 of the ray — is in relation to the complete consideration of the light- 

 effect lüüh observance of the diffraction, in which therefore the 

 ivhok space behind the aperture is affected by the light, and of 

 which it is possible to determine the distribution of the intensity. 



Appendix. Complete derivation ') of (4). 



If a fraction ,r., of 1 mol. is temporarily joined to double molecules, 

 a fraction ,i\ to triple molecules etc., we have therefore: 



»j = 1 — .^2 — A'a . . . single mol. ; n^ =z 7, ,v^ double mol. ; 

 »3 = 7j ,v^ triple mol. ; etc. 

 If further generally : 



b = n^b^ -f ti^b^ + n^b^ + . • 5 

 then 



bz={l —X, - .^3 — ...)&,+ V'. -^'2 ^2 + V3 ■^•3 ^3 + • • •' 

 or 



b = b,- cc, {b, - 7, b,) - X, {b, — 73 h,) — . . . 



In this 61 — 7., h^ = L^b represents the change of h, always when 

 a half double molecule dissociates to a single molecule; h^ — Vs ^z = ^J> 

 the change of b, when one third triple molecule dissociates to a single 

 mol.; etc., so that we can also write: 



b^nb^ — x^ L^b — .1-3 l^ib — etc («) 



That a does not change in consequence of the association, is known. 

 For three kinds of molecules e.g. holds namely : 



^) Ah'eady dorived by me in 1908, but never published. 



