The Power of a Locomotive Boiler

How it is Calculated

Practical Limit to the Depth of Mines

What the Steam Pump has done

How Fish are Hatched—V

Fish-Cultural Practices in the United States Bureau of Fisheries

Gilding Glass

The Mount Wilson Conference

The International Union for Co-Operation in Solar Research

Exploring the Dead Sea in a Motor Boat

Norwegian Water Power and the Nitrogen Industry

A New View of the Migration of Birds

Ultra-Microscopic Particles

What is Ultra-Microscopy?

The Physiological Effect of Magnetism

The Mechanics of Saving Life—III

Safety Provisions in the United States Steel Corporation

Two Interesting Experiments with Carbon Dioxide

The Constitution of the Earth's Interior

A Review of Recent Geologic Theories

Engineering notes

Science notes

Trade Notes and formulæ