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SCIENTIFIC AMERICAN SUPPLEMENT NO. 312




NEW YORK, DECEMBER 24, 1881.

Scientific American Supplement. Vol. XII., No. 312.

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. ENGINEERING AND MECHANICS.--Improved Fifteen Ton Traveling
Crane. Designed for service in the construction of Port