Between them was
packed a mixture of coke to supply the carbon, sand to supply the
silicon, sawdust to make the mass porous and salt to make it fusible.
[Illustration: The first American electric furnace, constructed by
Robert Hare of Philadelphia. From "Chemistry in America," by Edgar Fahs
Smith]
The substance thus produced at Niagara Falls is known as "carborundum"
south of the American-Canadian boundary and as "crystolon" north of this
line, as "carbolon" by another firm, and as "silicon carbide" by
chemists the world over. Since it is next to the diamond in hardness it
takes off metal faster than emery (aluminum oxide), using less power and
wasting less heat in futile fireworks. It is used for grindstones of
all sizes, including those the dentist uses on your teeth. It has
revolutionized shop-practice, for articles can be ground into shape
better and quicker than they can be cut. What is more, the artificial
abrasives do not injure the lungs of the operatives like sandstone. The
output of artificial abrasives in the United States and Canada for 1917
was:
Tons Value
Silicon carbide 8,323 $1,074,152
Aluminum oxide 48,463 6,969,387
A new use for carborundum was found during the war when Uncle Sam
assumed the role of Jove as "cloud-compeller.
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