Skip to main content


The Microscope in Metal Study

Some of the Difficulties of Illumination and How They Are Met

By Henry M. Sayers

Effect of Water on Strength of Concrete

Corrosion of Brass in Sea Water

By Paul T. Bruhl

Birds and the Farmer

The Hawks of the Canadian Prairie Provinces in Relation to Agriculture

By P. A. Taverner

Radium and Radio-Activity—II

A Consideration of Some of the Physical and Chemical Aspects

By Charles H. Viol

“Protactinium,” a New Radio-Active Element

Lateral Deviation of Projectiles

Lost City

The Forgotten Dwellings of a Forgotten People in New Mexico Photographs copyright by E. M. Newman

By Charles d*amp*apos;Emery

Textile Fibers in Germany

Wind Circulation of the Globe

The Mineral Elements in Animal Nutrition

With Special Reference to Source and Administration of Iodine and Phosphorus

By E. B. Forbes

A Scientific Coin Problem

How Some Mysterious Numerical Effects Can Be Produced

By Theodore L. De Land

Hints for Photographers from Motion Pictures

Digestibility of artificially Dried Feed

Analysis of the Mechanism of Speech

The Yellowing of Paper

A Study of the Causes or Principal Factors Producing this Deterioration

By Alfred B. Hitchins

The Lens for a Studio

Nature's Factories for Sugar and Starch

Ocean Temperatures and Seasonal Weather in Southern California

(Extracts from open letter, dated La Jolla, Cal., Nor. 8, 1918)

By Wm. E. Ritter and Geo. F. McEwen

The Testing of Cotton by Steaming


    Purchase To Read More

    Already purchased this issue? Sign In to Access
    Select Format
    Scroll To Top