AQUEOUS SOLUTIONS.—-MCKAY. 329 
The mean of these ratios is .2131. This was taken as the 
calibration constant, and by means of it the conductivities of 
solutions measured in the first cell were expressed in Kohl- 
rausch’s units. The capacity of the second cell was determined 
in the same manner. It will be seen that the solutions above, 
which show the closest agreement with Kohlrausch’s values, are 
those which could be measured near the middle of the bridge, 
viz., those of concentrations 0.5 and 5 gramme-equivalents per 
litre. 
Observations on Simple Solutions. 
The following tables give the concentrations and the conduc- 
tivities of the simple solutions of NaCl and BaCl,, by means of 
which the curves that show the relation between the ionic con- 
centration and dilution were drawn.* The concentrations are 
expressed in gramme-equivalents per litre for the temperature 
of 18°C. The conductivities are expressed in terms of the 
conductivity of mercury at 0°C, multiplied by 10~°, the tempera- 
ture being also 18°C. 
* See paragraph on making up of solutions. 
