PRESENT PROBLEMS 695 



on the one hand, and the State Boards of Health on the other, are 

 constant stimuli to increased effort toward their utilization. 



Although I have endeavored to select the above examples of un- 

 solved problems with a view to touching upon as large a portion of 

 the field of technical chemistry as possible, I could doubtless, with 

 equal propriety, have selected others. We can simply mention such 

 important questions as the hygienic preservation of food, the flame- 

 proofing and preservation of wood, prevention of the corrosion of 

 structural iron and steel, the great problems of chemical metallurgy, 

 etc. We must, however, note some of the more recently developed 

 forces and phenomena of nature, the application of which to tech- 

 nical chemistry forms problems for to-day. One of the most im- 

 portant of these is electricity. Thanks to the triumphs of modern 

 electrical engineering we are now able to call to our aid unlimited 

 amounts of this agent at a cost comparable to that of other forms 

 of energy. Possibly the simplest, though not the earliest method of 

 utilizing electrical energy in chemical processes is in supplying the 

 heat necessary to carry on a reaction directly at the point where the 

 reaction takes place. In a number of chemical industries (for example, 

 the manufacture of phosphorus) it was previously necessary to pro- 

 duce within thick-walled retorts a very high temperature. The result 

 was that a great deal of heat was wasted, the retorts deteriorated 

 very rapidly, and the reaction was carried on at a low efficiency. By 

 using an electric furnace for the manufacture of phosphorus these 

 expensive retorts are eliminated. In addition much cheaper raw 

 materials may be used, the process is made continuous, and a high 

 efficiency obtained. By the substitution of electrical heating for the 

 closed retorts previously used in the preparation of carbon bisulphide 

 the manufacture of this chemical has been placed upon an entirely 

 new basis. The economy introduced by supplying the heat at the 

 point where the union of carbon and sulphur takes place is clearly 

 indicated by the low price at which this material can now be sold and 

 its enormously increased consumption. 



With the ability to obtain temperatures far above that which is 

 possible by the ordinary combustion of fuel, there was opened up a 

 new field in synthetic chemistry. Reactions which it was impossible 

 to carry out on a technical scale, and others, the existence of which 

 was not suspected, have now, through the application of electrical 

 energy, become the bases of large manufacturng enterprises. Calcium 

 carbide, carborundum, artificial graphite, and many hitherto un- 

 known alloys are the commercial products of the electric furnace 

 where temperatures in the neighborhood of 3000 C. obtain. 



The third and more strictly chemical application of electrical 

 energy is in the use of the current for electrolysis. Faraday long ago 

 determined the laws according to which chemical compounds break 



