710 Prof. I. Traube: Contribution to the Theories 
I 
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t Dee 
3 mm. 
Tsobutyil alicohial: 22: 273.2 cers eae keene eee | 20 31:5 
Tsoaniayl aleoliol ya? saits. scec cuneate nem tease | i | ao°d 
Rifliy! ether 'y sees ere to eae eee eee PAS Pa See 
Angling batted dRee Bed ce eee Mon 55:0 | 
Methyl acetate... 5, 37. .tee coker earn eens eeeaneee ids 34-7 | 
Rily) nestale: | A: acces thie- anes e yee > eeek tase eee | o <38:0 4 
Propyltacetiate v.02 ie tte ae hae eas Baa eat nae) 
\sdisoburty] acetate) mls nene- cps 32 eteh en aeneeeee Yo | ee 
} Asoniniiyl Seetate \ Peso. 4! anteemtwsnomenteet onan sent | : Le tec 
| Ethyl alcohol +benzene-+ water ...............6+. | i Somme 
| Isobutyl aleohol+aniline+ water ............... | : | 45°5 
| Gia ligro borne 8.0 oo .c en te none eee eaae ) 19 | 82°5 | 
Biliyl todides Jl9),00sb ster d cas oleae eee * 87:0 
| Hthylenie chlorite. «ocuc. ci ndasueapeeaans so seamres | ‘ | 80°25 
As the numbers given for the esters and other compounds 
(chloroform, ethylene chloride, &c.) show, the capillary height 
of the solution is not always equal to that of the dissolved 
substance ; but, except for the small difference in the case of 
isobutyl alcohol, it is never lower ; and even this is no excep- 
tion, if we take the real constant of surface-tension, i.e. the 
product of capillary height and density instead of the capillary 
height. On the other hand, the capillary heights of the ester 
soluti ons, particularly ot ‘those of compar atively high molecular 
weight, have probably been read at considerably above their 
true position, since by reason of the low dissolving tension of 
these esters, and the consequent incessant evaporation, 
constant rising goes on in the superficial layer. 
Thus we see that solubility, solution-texsion, and surface- 
tension are all in the closest mutual relationship. 
The highest attainable value of the surface-tension ef a 
saturated solution is that of the dissolved substance. Conse- 
quently the surface-tension of the dissolved substance determines 
the shape of the curve of the surface-tension of solutions. 
If we apply the interpolation formula 
Y=athg or y=atbhg+cq’, 
where y is the surface-tension of an aqueous solution con- 
taining a percentage of water g, then a will stand fairly approxi- 
mately for the surface-tension of the pure substance, if the 
content of water is g=0. This explains the fact, mentioned in 
former publications of mine, that the solutions of salts and of 
ithe greater number of solid organic substances are inactive 
as regards capillarity, 7.e., do not appreciably lower the 
capillary height of water. The reason is, that solid substances 
have a higher surface-tension than liquids. 
