INDUSTRIAL ELECTRO-CHEMISTRY 151 



his process in which chlorine passes through an ingenious 

 cycle, paid proper attention to the fundamental require- 

 ment that pure solutions must be provided and maintained. 



An interesting and novel electrometallurgical process 

 which, however, has not yet attained industrial importance, is 

 Salom's reduction of lead from galena by direct cathodic 

 reduction. 



That class of processes in which chemical efforts are pro- 

 duced by discharges through gases is the youngest in the de- 

 velopment of industrial electrochemistry. Commercial suc- 

 cess has been achieved abroad with the production of ozone 

 from air and the subsequent use of ozone for sterilizing 

 water. If the cost is not prohibitive, there should be a 

 commercial future for such processes in this country. Great 

 interest has been aroused by the Bradley-Love joy process 

 for the fixation of nitrogen from the air. The process is 

 still in its experimental stage and a successful issue would have 

 a revolutionary effect in many branches, particularly in ag- 

 ricultural chemistry. The variety of possible methods is 

 indicated by the utilization of the silent discharge in ozonizers, 

 while Bradley and Lovejoy produce arcs, but so finely sub- 

 divided as to give a large surface for small energy. 



This cursory review does not nearly exhaust the subject 

 of producing chemical effects by electrical means, but it is 

 hoped that it gives at least a general idea of the achievements 

 of the past and of the possibilities of the future, together 

 with some general principles which should always be kept 

 in mind in connection with this subject. We may be per- 

 mitted to treat even more briefly the reverse problem, that 

 of producing electrical from chemical energy. 



There is not much to be said concerning primary bat- 

 teries. Their limitations, if zinc is used as fuel, have been 

 pointed out above. The problem has, therefore, been to 

 substitute carbon for zinc and to devise a carbon cell. 

 The effect would be commercially far reaching. At present 

 we burn the coal in connection with boilers, steam engines 

 and dynamos and thus produce electrical energy by a round- 

 about method, with a low efficiency, since the efficiency of 

 the steam engine is limited by the principles of thermody- 



