THE USE OF THE VIBRATION GALVANOMETER WITH 
A 60-CYCLE ALTERNATING CURRENT IN THE 
MEASUREMENT OF THE CONDUCTIVITY 
OF ELECTROLYTES 
Newton B. Green 
In 1898 Kohlrausch (i) published a description of his method for 
determining the conductivity of electrolytes, and since that time much 
has been done by various investigators to increase the accuracy of the 
method. Notable among these are E. W. Washburn (2) and R. P. 
Hibbard in collaboration with C. W. Chapman (3). Still more 
recently has appeared an article by W. Taylor and S. F. Acree (5), 
Among the sources of error, which they have removed, may be men- 
tioned the following: an alternating current from an induction coil 
which is neither strictly alternating nor of constant frequency; resis- 
tance coils which are inaccurate because of capacity and inductance; 
and lack of sensitivity in the telephone detector. At the present 
writing a series of articles is appearing in the Journal of the American 
Chemical Society by Dr. Washburn (4) which sums up the latest 
researches on the subject. To these articles any investigators who 
desire absolute accuracy of results are referred. The plant physi- 
ologist is concerned more with precise comparative data than with 
absolute physical accuracy, which must of necessity include experi- 
ments extending over long periods of time and involving great* elabora- 
tion of method. 
Dr. Washburn's method overcomes the difficulties mentioned above 
in the following manner: He uses for a source of current either the 
Vreeland Oscillator, which gives a pure sine wave at a frequency of 
one thousand cycles per second, or a constant-speed high-frequency 
generator which delivers an alternating current at the same frequency. 
Both of these pieces of apparatus and the principles involved are 
described in Catalog No. 48 of the Leeds and Northrup Co. (6). For 
resistance coils he uses the Curtis type, which have a minimum of 
inductance and capacity, and for the detector he uses a telephone 
receiver tuned to the frequency of the current. He also finds it 
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