CHEMISTRY: E. W. WASHBURN 
571 
sufficient importance to make the attempt worth while. Accordingly, 
with the aid of a grant from the Bache Fund of the National Academy, 
the investigation was begun in 1911. 
The first part of the problem consisted in developing and perfecting 
the Kohlrausch method for measuring the conductance of electrolytes 
so that an accuracy of better than 0.01% could be obtained in measur- 
ing the conductance of very pure water and of these very dilute solu- 
tions. With the valued assistance of Dr. J. E. Bell and Mr. Karr 
Parker this part of the problem was successfully solved, and the results 
have already been published.^ 
FIG. 1 
The second part of the problem resolved itself into the preparation 
of large quantities of conductivity water whi^ch should be practically 
chemically pure, and the preservation of the purity of this water during 
the operations of preparing and measuring the conductivity of the solu- 
tions. This was successfully accomplished by means of a large quartz 
still connected to a three-liter quartz conductivity cell provided with 
platinum electrodes sealed into quartz tubes, the distillation being 
carried out in a current of carefully purified air. In this way three 
liters of conductivity water having a specific conductance at 18° of 
only 0.05 X 10-^ reciprocal ohms could be obtained and preserved in 
the conductivity cell for at least 12 hours without any appreciable 
increase in its specific conductance. The solutions were made up by 
