FRANCIS P. VENABLE, Ph.D., D.Sc., LL.D.

PROFESSOR OF CHEMISTRY, UNIVERSITY OF NORTH CAROLINA
AUTHOR OF
"A SHORT HISTORY OF CHEMISTRY,"
"PERIODIC LAW," ETC.

D. C. HEATH & CO., PUBLISHERS
BOSTON NEW YORK CHICAGO

Copyright, 1917,
By D. C. Heath & Co.
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