thought lliis might have heen doiio hy niuUiplicalion by a factor 



n—o 



— — — . That lie tailed to do so deprives his test of the experimenlal 

 data of much of its vahie, in my opinion. 



§ 3. Test of the foriiudae for liquids not too iwar tlie critical 

 point. Let ns call the "coefficient of friction by means of transport" 

 1]^, that through forces of collision i^,, and that in consequence of 

 formation of groups »;,. For liquids not too near the critical point 

 we shall disregai-d i]^. We have furthei": 



in which c is a numerical coetïicient of moderate value. We may 

 no doubt consider this (piantity as lai-ge compared with i, so that 

 we shall also neglect ij^. 



When we do so we notice lirst of all that for constant volume 

 ii accoi'ding to the formula must increase with T proportional to 

 [/T. There are only few substances for which the experimental 



data are available, required to verify whether tlie sign of is 



dT, 



really positive. It is clear that always ^-; has been measured, and 



2'p 



not ~- . Father and Benzene are the onlv substances for which I 

 01 r 



have found records for ^ — '), so that - — can be found according 



to the foi'inula 



1 dv 



I dii 1 d»; 1 d»; dp 1 dtj 1 dtj v dl], 



7jd7'„ ndl], ridp^^.dT,. y dl), '»i op 1 dv 



We find: 



for ether for benzene 



1 dii 



.— = — 0,01075 ') —0,01853 ') 



1) Except for water, which will most likely also behave abnormally in this 

 respect, and for CO., in the neighbourhood of the critical point, which observations 

 will be discussed later on. 



-) These values, like those of c-^ for other substances given below have 



