The Methods and Instruments used in Astrophotography

Curious Weapons

The Boomerang and its Origin—War Quoits and Knobkerries—the Blowpipes of the Dyaks

Green Fruit Worms

Selected Formulæ

Electrical Notes

Engineering Notes

Miscellaneous Notes

Gravitation Stamp Mills for Quartz Crushing

Apparatus for Cooling Water of Condensation

Foster's Film Evaporator

The Progress of Gas Engines

Lessons from American Railroads as to Cheap Transportation

The Hotchkiss Automatic Machine Gun

Fuel Energy into Electrical Energy

The Practice of the Combined Open Hearth Process of Messrs Bertrand & Thiel

The Theory of Dreams

Labor Insurance in Germany

Patents!

Influence of Intellectual Work on Blood Pressure

Fuller's Earth