1040 
correction in this manner, which, with great dilutions, can cause a 
difference in the value of A of several percentages. When now we 
represent their results of 4, graphically asa function of the logarithm 
of the dilution, the curved lines in the vicinity of WV = 2000 and 
higher often exhibit very peculiar bends so that sometimes the 
graphical approximation of 4, becomes impossible. ‘The curved lines 
deduced from my results all appear to run asymptotically with a 
line parallel to the dilution axis, as required by theory. 
The approximation of 4,, particularly at 100°, is rather uncertain, 
because with very great dilutions the above described correction 
method for the conductivity water also fails. In order to get com- 
parable results, [ have applied the empirical method of BrEDIG ') 
and of Norrs®) taking A= Aco + 2,5 N at 25° (NV = product 
of the valencies of anion and eation). I have chosen the coefficient 
of VN at O° so much smaller and at 100° so many times larger as 
the proportional decrease and increase of 4,,,, amounts to at those 
temperatures. 
In the measurements at 100° which were carried out in a steam- 
bath, the solution being kept under a pressure of 5 atm. to prevent 
evolution of vapour at the electrodes, a correction had to be applied 
for the influence of the barometer indication on the steam-temperature. 
For this purpose the temperature coefficient of 4 of the different 
salts as determined by Jones’) between O° and 65°, was used with 
a proportional reduction to 100°. 
Here follow the thus corrected results of 7 at different dilutions 
(V) at O° and 100°. For each measurement the concentration at 
15° was determined separately and in this way eventual errors 
caused by pipetting off and delivering into the measuring vessel 
were avoided. 
The depression of the solidifying points was determined according 
to the method of Ronertson and Wanker *) in which corrections for 
the influence of the radiation and for the slowness with which the 
temperature exchange takes place, are done away with. The liquid 
siphoned off from the ice-saltsolvent mixture was rapidly brought to 
the temperature of the room and titrated. The thermometer in the 
Dewar vessel remained constant for a considerable time when this 
vessel was properly surrounded by ice. 
The concentrations all relate to a temperature of 15°. 
1) Zs. phys. Chem. 18. 191. (1894). 
2) Technol. Quart. 17. 293 (1904). 
3) Carnegie Inst. of Washington, publ. 170 (1912). 
4) Proc. Royal Soc. 24, 363 (1902). 
