Looking Ahead With the Editor, September 1929
What the New Planetariums for Chicago and Philadelphia Will Be Like
This Age-old Sweetmeat, Medicine, and Sacred Herb Links the Modern World With Ancient Peoples and Religion
An Understanding of the Importance of Natural Gas Replaces Misconceptions About "Oil Pools" and "Rock Pressure"
Rich Mineral Areas Amid Lakes and Forests of Northern Canada Mapped Accurately for the First Time
The Tank Promises to Force a Reorganization of Armies for It Is Now Much More Formidable Than During World War Days
The Stars Send Out Their Light into Empty Space. Does It Go On Forever? If Not, Where Does It End?
A Summary of the Opinions, pro and con, of Men High in the Aeronautical Industry
A Witness Describes This Fascinating Process
The Invisible Guardians of Wealth Are Little Clocks and Disks of Metal
Two World's Largest Zeppelins for Our Navy Will Be Built in Huge Hangar Now Arising at Akron, Ohio
Question of Steam versus Hydro Generation of Power is Being Answered by Improvements in Steam Power Equipment
A Suggestion of the High Engineering Refinement Involved in This Highly Specialized Problem
A California Community of Over Two Thousand Five Hundred Depends on Grape By-products Which Can Be Legally Sold
A Fascinating Archeological Discovery by Aerial Photography, a Method Now Being Developed in Europe