Free Ions in Aqueous Solutions of Electrolytes. 241 



Ostwald says that the amount of gas liberated would be too 

 small to be seen, and so, as before stated, he does not attempt 

 the experiment, bat a year later, together with Nernst, gives 

 the experiment previously mentioned. 



It was believed that an electrostatic charge would attract 

 and repel the unlike and like charged ions respectivel3\ And 

 as it is the ions which in giving up their charge produce a 

 current, then if these ions could be guided by an electrostatic 

 charge we should get a current with electrodes indifferent to 

 the solution, and be able to detect it with a sufficiently delicate 

 galvanometer. 



These were the beliefs upon which the following investiga- 

 tion was founded. 



The experiments were performed on a brick pier capped 

 with a granite slab and entirely independent of any vibration 

 of the building. A delicate Jfeowland galvanometer together 

 with a telescope aud scale was used. The scale was about 

 25g.Qcm fpQm the mirror of the galvanometer. The deflections 

 were read to O'l"'". 



A U-tube was first used, into which were placed platinum 

 wire electrodes. The wires were wound into a spiral in order 

 to increase the surface exposed. Before putting them in, the 

 electrodes were heated to a white heat in a blowpipe flame. 

 Distilled water and a trace of sulphuric acid was used. It was 

 found that the cell always gave a deflection ; however, it was 

 intended to take the deflection first, before an electrostatic 

 charge had acted upon the solution, and then taking out the 

 electrodes, let a charge from an electrophorus act upon the solu- 

 tion for some time and then put in the electrodes and take 

 the defiections again. 



It was found that an electrode taken out of dilute sulphuric 

 acid and exposed to the air while the other remained in the 

 solution was, when replaced, strongly negative. As this effect 

 was so decided, and the exposure of the two electrodes could 

 not be made of exactly the same duration, nothing could be 

 gained from this method. 



A cell was now made from a low round beaker about 53'0^™ 

 in diameter. Platinum foils 2x2"5^°' were welded to plati- 

 num wires which were run up through corks in a piece of 

 wood that served as a cover for the cell. The foils were bent 

 so as to fit around the curvature of the beaker and be about 

 2.QHim (;|igtant from its edge. The cover of the cell was held in 

 place by small nails driven into it from the under side, and it 

 could be turned around so as to bring the electrodes into any 

 desired position around the edge of the cell. 



The cell was placed on a wooden stand in such a way that the 



