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SCIENTIFIC AMERICAN SUPPLEMENT NO. 315




NEW YORK, JANUARY 14, 1882.

Scientific American Supplement. Vol. XIII., No. 315.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.

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TABLE OF CONTENTS.


PAGE
I. ENGINEERING AND MECHANICS.--Watchman's Detecter. 5023