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SCIENTIFIC AMERICAN SUPPLEMENT NO. 447




NEW YORK, JULY 26, 1884

Scientific American Supplement. Vol. XVIII, No. 447.

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.--The Bitter Substance of Hops.--By Dr. H. BUNGENER.
--What gives hops their bitter taste?--Processes for obtaining
hop-bitter acid.--Analysis of the same.

II. ENGINEERING AND MECHANICS.--Improvements in the Harbor