174 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1911. 
an instant partakes of the enormous temperature, and on leaving the 
are is cooled as quickly as possible. In the are 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 felow members, has 
recently solved the problem of its production by an adaptation of the 
‘‘oxygen-nitrogen”’ are apparatus and utilizing the same principle 
of introducing the material into the are 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. 
LiL. 
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 
