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A Submarine Plow for the Submarine Telephone Cable, New Way of Singeing Chickens and more

Our Tropical Timber Trade

Some of the Valued Woods for Which We Must Rely Upon the Countries to the South of Us

By Samuel J. Record

Weighing the Ten-Millionth of a Milligram

By A. Gradenwitz

The Burning Mines of the Hocking Valley

By Harry A. Mount

Revolutionizing an Industry

How Modern Machinery Is Minimizing Hand Labor in Hemp Production

By George H. Dacy

Is the Practical Helicopter in Sight?, Measuring Vapor Pressures and more

By George Gaulois

Reorganizing Our Government Machinery--II

Some Concrete Reasons Why Rearrangement for Mere Rearrangement's Sake May Not Be a Good Thing

By C. H. Claudy

A New Era in Wireless

What Is Being Done With the Radio Telephone By Way of Broadcasting News, Music and Sermons

By L. H. Rosenberg

A Study in Magnitude

Comparison of the Hudson Riverbridge with Some of the World's Largest Constructions in Engineering and Architecture

By J. Bern Walker


  • Departments


  • The Heavens in June, 1921

  • Inventions New and Interesting

  • Recently Patented Inventions

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