Free Ions in Aqiteoiis Solutions of Electrolytes. 243 



The jars in connection with the disk were charged only 

 when in positions (1) or (J:), and discharged before the elec- 

 trodes were turned into positions (2) or (3). 



The galvanometer circuit is kept open except at the moment 

 of taking a deflection. The direction of the galvanometer 

 needle was determined beforehand. 



The time between each deflection in the different series was 

 generally 2 or 5 minutes. I will describe a 20-minute series, 

 deflections being taken every 2 minutes, starting from posi- 

 tion (1). 



Before the jars were charged, the deflections were taken 

 in position (1) every 2 minutes for 20 or 30 minutes or until 

 the deflections became about uniform ; then the cover of cell 

 together with the electrodes were turned through 90° into 



1 



Position 1, 



Position 2. 



Position 3. Position 4. 



position (2), say. The turning was done very slowly and care- 

 fully so as not to disturb the liquid more than necessary, and 

 care was also taken to avoid shaking or turning the cell. The 

 deflections were then taken in position (2) every 2 minutes for 

 20 minutes, and then the electrodes were turned 180° through 

 the flrst position into position (3), and the deflections taken in 

 that position every 2 minutes for 20 minues. These readings 

 would indicate the condition of the liquid at positions (2) and 

 (3) before being acted upon by an electrostatic charge, and 

 comparing these readings with the readings after the solutions 

 has been acted upon by a charge would show the effect of the 

 charge. 



After the condition of the liquid was determined as above 

 stated, the electrodes were turned into position (1) and the jars 

 in connection with the disk charged positive or negative by 

 the friction machine. The charge was allowed to act for the 

 same interval of time as was used before, namely, 20 minutes, 

 and the deflections taken in this position also, in order to keep 

 the cell always in the same condition, that is, deflections were 

 taken every two minutes throughout the entire experiment. If 

 the cell is allowed to rest even a few seconds over the regular 

 interval, a change in the amount of the deflection is noticed. 

 The cell runs down quickly and recovers quickly. 



