374 PROCEEDINGS OF THE AMERICAN ACADEMY. 



Sodium Hydroxide 0.015 N Cloud. 



.020 JY very slight cloud and bubbles 

 at anode, 

 above .020 N Only bubbles at anode. 

 Sodium Chloride 0.0005 A T brown cloud, soluble in drop of 



acetic acid. 



.001 N br °y n l clouds brown soluble 

 white J white insoluble 



above .001 N white cloud only. 



(6) While the above effects are making their appearance in the 

 electrolyte at slight distances from the electrodes nothing whatever 

 happens at the kathode itself. The space between the electrodes may 

 be active for several minutes without the appearance of either a 

 bubble of gas or a crystal of silver. If very thin silver foil is used for 

 electrodes solvent action on the anode is very evident and it is rapidly 

 dissolved. A thin silver foil kathode shows signs of dissolving at the 

 edges during the first minute or so of the passage of the current, but 

 the action ceases immediately. 



(7) There seems to be a limiting voltage below which these phe- 

 nomena do not make their appearance. This is very close to 1.41 

 volts for electrodes 1 mm. apart. The upper limit of voltage, above 

 which gas appears at the electrodes, is about 3.8 volts. 



(8) Even in purest distilled water the phenomena are much more 

 complicated than those so far described. The anode and kathode 

 clouds are quite different in their behavior. That from the kathode 

 appears to be composed of particles shot off at random, and these 

 particles do not take any definite path after leaving the neighborhood 

 of their parent electrode. The anode cloud, on the contrary, sticks 

 closely together, and if the electrodes are at the mouth of a deep test- 

 tube filled with water the anode cloud travels to the very bottom of 

 the tube in such close coherence that it looks like a thin brown thread. 



(9) The effect of a magnetic field on the behavior of these particles 

 has been tried without definite result. They are relatively so large, 

 and they move so slowly that an effect is hardly to be anticipated. 



Attempt has been made to follow the changes in weight at each 

 electrode during the electrolysis. The micro-balance wa.s adapted for 

 this purpose as shown in Figure 3. It is of course quite impossible to 

 use any arrangement in which a fibre passes through the liquid sur- 

 face. The effect of surface tension is far too great. But by placing 

 both fibres and conducting wires under the surface of the electrolyte 



