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SCIENTIFIC AMERICAN SUPPLEMENT NO. 531




NEW YORK, MARCH 6, 1886

Scientific American Supplement. Vol. XXI, No. 531.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.


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TABLE OF CONTENTS.

I. CHEMISTRY AND METALLURGY.--Annatto.-Analyses of the same.--By
WM. LAWSON

Aluminum.--By J.A. PRICE.--Iron the basis of civilization.--
Aluminum the metal of the future.--Discovery of aluminum.--Art