174 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1911. 



an instant partakes of the enormous temperature, and on leaving the 

 arc is cooled as quickly as possible. In the arc the combination of 

 nitrogen and oxygen is effected to a certain extent, and the mixture 

 is cooled so suddenly that it does not find time to disunite. The 

 nitrogen oxides thus obtained are drawn through water, and this 

 solution of nitric acid is run upon soda to produce sodium nitrate or 

 on lime to produce calcium nitrate, the latter called nitrolime or 

 "Norwegian saltpeter." These salts entirely replace the South 

 American natural salt. 



The materials used in this industry are air and lime, and to these is 

 added electrical energy. Air is universal, lime cheap almost every- 

 where, and electrical energy is cheapest where water powers are most 

 abundant. In Norway water power can be developed and electrical 

 energy supplied from it at a total cost of $4 to $8 per horsepower year. 

 Some other countries can do nearly as well. Under these conditions, 

 almost every country can afford to make its own nitrates and so be 

 independent of other countries for the fertilizer needed in peace and 

 the gunpowder used in war. Norway felicitates itself already on 

 being thus independent. Nearly 200,000 horsepower is being utilized 

 there by a $15,000,000 syndicate, and the industry is spreading 

 rapidly over Europe. The study of this problem, its solution, and 

 the rapid development of this vigorous industry, is one of the most 

 remarkable chapters in the history of recent industrial development. 

 In this accomplishment electrochemistry has signally aided the agri- 

 culturist and demonstrably multiplied the food-supply resources of 

 all civilized and highly populated countries. 



Boron is an element which has until recently defied the best efforts 

 of chemists to isolate in a pure state. It is an element which may 

 have important application in the manufacture of a high-class special 

 steel — boron steel. Dr. Weintraub, one of our fellow members, has 

 recently solved the problem of its production by an adaptation of the 

 "oxygen-nitrogen" arc apparatus and utilizing the same principle 

 of introducing the material into the arc and very rapidly cooling the 

 products obtained. We mention this not because of its great commer- 

 cial importance at present, but because it shows how the "arc method " 

 may be of wide application in solving other difficult chemical prob- 

 lems.. It has opened before us a new method in chemical science, and 

 may give birth to many and various new chemical industries. 



III. 



Electric furnaces are furnaces in which the necessary heat or 

 degree of temperature is produced or attained by means of electrical 

 energy. The electric current is used in these furnaces solely for its 

 heating or thermal effect, and either alternating or direct current may 



