charged with a solution of common salt, through which a current of electricity is then passed, thus decomposing or splitting up the salt into its elements, chlorine and sodium.  In the separation of the sodium, however, a secondary action takes place, which converts it into caustic soda.  An automatic circulation of the solutions is maintained by placing the charging tanks at a slight elevation, and the vessels themselves on platforms arranged in steps.  The solutions are pumped back from the lowest vessel to their respective charging tanks, the salt solution to be further decomposed and the caustic soda solution to be further concentrated.  The chlorine gas evolved in the fifty anode sections is conveyed by means of main and branch tubes into several absorbers, in which milk of lime, kept in a state of agitation, takes up the chlorine, thus making it into bleaching or chlorate liquor as may be required.  If the chlorine is required to be made into bleaching powder, then it is conveyed into leaden chambers and treated with lime in the usual manner.  The caustic soda formed in the fifty cathode sections is more or less concentrated according to the particular purpose for which it may be required.  If, however, the caustic soda is required in solid form, and practically free from salt, then the caustic alkaline liquor is transferred from the electrolytic vessels to evaporating pans, where it is concentrated to the required strength by evaporation and at the same time the salt remaining in the solution is eliminated by precipitation.

Such is the method of manufacturing caustic soda and chlorine by this process, which will doubtless have a most important bearing upon many trades and manufactures, more particularly upon the paper, soap, and bleaching industries.  But the invention does not stop where we have left it, for it is stated that the process can be applied to the production of sodium amalgam and chlorine for extracting gold and other metals from their ores.  It can also be utilized in the production of caustic and chlorate of potash and other chemicals, which can be manufactured in a state of the greatest purity.  A very important consideration is that of cost, for upon this depends commercial success.  It is therefore satisfactory to learn that the cost of production has been determined by the most careful electrical and analytical tests, which demonstrate an economy of over 50 per cent. as compared with present methods.  Highly favorable reports on the process have been made by Dr. G. Gore, F.R.S., the eminent authority on electro-chemical processes, by Mr. W.H.  Preece, F.R.S., and by Messrs. Cross & Bevan, consulting chemists.  Dr. Gore states that the chemical and electrical principles upon which this process is based are thoroughly sound, and that the process is of a scientifically practical character.  Should, however, the economy of production even fall somewhat below the anticipations of those who have examined into the process very carefully, it can hardly fail to prove as successful commercially as it has scientifically.