Interior of a naphthalene subliming house. 

 The vapor passes into this chamber and 

 crystallizes on the ceiling and in the air 



At the right are shown tanks in which crude 

 naphthalene crystallizes out of light oil. 

 After several days, the oil is drained off 



and child in the United States were to use 

 a pint of last year's benzene for cleaning 

 purposes, there would still be left enough 

 to furnish each inhabitant of the District 

 of Columbia with another pint. This enor- 

 mous increase has been more than offset 

 by the simultaneous increase in the demand 

 for explosives. 



Ancient signs and wonders pale when we 

 consider the stupendous importance of coal 

 tar. The indigo annually consumed in the 

 United States would buy army rifles for 

 62,500 United States troops. The sulphur 

 black used in one year weighs as much as 

 two ordinary passenger trains of ten cars 

 each, including the locomotives. The tech- 

 nical name for sulphur black is di-nitro- 

 oxy-di-phenyl-amine. Think of the millions 

 of pairs of ordinary black socks dyed that 

 color! 



More than twice as much naphthalene 

 is being used as before the war. It has 

 largely taken the place of camphor. At 

 present it is being used, not so much for 

 exterminating moths, as for killing men, 



since this important coal tar "intermediate" 

 is employed largely in the manufacture of 

 explosives. In 1916, 3,500 tons were pro- 

 duced in the United States. 



It is estimated that in 191 7 over 300,000,- 

 000 gallons of tar, or 3,000,000,000 pounds 

 will be used. Of this, 1,800,000,000 pounds 

 will become pitch, leaving 1,200,000,000 

 pounds for dyes, medicines, disinfectants, 

 explosives and other similar products. 



Before the war, aniline oil, which is de- 

 rived from benzol, and which is so impor- 

 tant in making aniline colors, was not 

 manufactured to any extent in the United 

 States. It was furnished almost exclusively 

 by Germany and England, the prices and 

 conditions being beyond our control. In 

 1914, imports dropped suddenly. The de- 

 mand for aniline oil became acute. Even 

 yet this precious chemical is not turned out 



