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SCIENTIFIC AMERICAN SUPPLEMENT NO. 520




NEW YORK, DECEMBER 19, 1885

Scientific American Supplement. Vol. Vol. XX, No. 520.

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, ETC.--Steel Structures.--Best use of different
grades of steel.--From a paper by Mr. JAS. CHRISTIE.

Natural Gas Fuel and its Application to Manufacturing:
Purposes.--Paper read before the Iron and Steel Institute by