ELECTROCHEMISTRY 151 



Electrolysis of Water: As a raw material, water may 

 be said to cost nothing. Apply an electric current to it in 

 the proper way, and it is resolved into its constituent gases, 

 hydrogen and oxygen, as cleanly and perfectly as any one 

 could desire. These gases have many and various uses, 

 and are valued each at several cents per pound. A whole 

 industry has thus grown up, based on the simple electrol- 

 ysis of water, to supply these two gases for various indus- 

 trial uses. Europe possesses many of these plants; there 

 are a few in the United States. The speaker has trans- 

 lated from the German a small treatise on this industry. 



Electrolysis of Salt: Common salt, sodium chloride, is 

 one of the cheapest of natural chemicals. It has some uses 

 of its own, but centuries ago chemists and even alchemists 

 devised chemical processes for transforming it into other 

 sodium salts, caustic soda or soda lye, for use in soap, soda 

 ash or carbonate, for washing or glassmaking, and into 

 chlorine bleaching materials. Chemical works operating 

 these rather complicated chemical processes exist on an 

 immense scale in all civilized countries; it is estimated that 

 $50,000,000 is thus invested in Great Britain alone. The 

 electrolytic alkali industry is barely twenty years old, yet 

 it is already more than holding its own with the older 

 chemical process, and advancing rapidly; twenty years 

 more will probably see the older processes entirely super- 

 seded they are at present fighting for their existence. As 

 for the electrolytic process, the salt is simply dissolved in 

 water and by the action of the current converted into 

 caustic soda at one electrode and chlorine gas at the other. 

 By some special devices these are kept separate and col- 

 lected by themselves, and the work is done. The principles 

 involved are simplicity itself as compared with the older 

 chemical processes, the only agent consumed is electric 

 energy, and the products are clean and pure. 



Chlorates: These are salts used on matches and in gun- 

 powder. Chlorate of potassium is a valuable salt with 

 important uses. It is made from common cheap potassium 



