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.