Copyright, Ewing Galloway

The drop forge. A fourteen-ton hydraulic press is employed in forging an immense open hearth steel plate.

Popular Science Library

EDITOR-IN-CHIEF

GARRETT P. SERVISS

AUTHORS

WILLIAM J. MILLER HIPPOLYTE GRUENER A. RUSSELL BOND
D. W. HERING LOOMIS HAVEMEYER ERNEST G. MARTIN
ARTHUR SELWYN-BROWN ROBERT CHENAULT GIVLER
ERNEST INGERSOLL WILFRED MASON BARTON
WILLIAM B. SCOTT ERNEST J. STREUBEL
NORMAN TAYLOR DAVID TODD
CHARLES FITZHUGH TALMAN
ROBIN BEACH

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VOLUME FIVE

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Copyright 1922
By P. F. Collier & Son Company

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