Scientific American Year 1931 Magazine Back Issues

Features
Synthetic Life From Chemicals - A New Advance
Why The Space Rocket? X Rays And Alloys
Modern Steel Mill Efficiency

Features
Automobile Number
Motor Car Review.. Diesel Bus... Trailers
Keep To The Right

Features
Companions In Depression - By Raymond B. Fosdick
Future Of The Rocket... Oil Prospecting By Airplane
Research On The Mystery Of The Aurora

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Vacuum Tubes In Industry
A New Use For Radium
Radio In Crime Detection
American Made Locomotives For Foreign Railroads

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An Industry That Was Made - To - Order
Which Races Are Best?
How Big Is A Quantum?
How The Aviator Sees A Rain-Bow

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New Ideas - The Life Of Industry Shall We Reform Our Calendar?.. Man's Inseet Allies
June 1931 35c A Copy
Triangulation - Building The Backbone Of Accurate Map's

Features
July 1931
Scientific American 35c A Copy

Features
Probing The Earth Beneath.... By Ernest A. Hodgson
Insects Versus Man.... By L. O. Howard
Progress And The Telephone... By F. D. McHugh
Food From Seaweeds.... By Crane And Thurston

Features
Is Science Approaching A Stalemate?... By Dr. Paul R. Hesl
Natural Gasoline From Oil Wells.... By Prof. G. Ross Robertson
Is Interstellar Space Empty?.... By Prof. Henry Norris Russell
A Hidden World In A Drop Of Water ... By M.C. Swingle

Features
Are Swimming Pools A Health Menace?... By Orson D. Mann
New Hope For The Cotton Industry... By Peter A. Carmichael
The Ether Theory Again Refuted.... By Harry Simon
Behind The Scenes Of News Gathering... By Albert A. Hopkins

Features
The Hottest Place In The Universe.... By Henry Norris Russell
Electrical Aids To Blind Flying .... By Alexander Klemin
Are The Planets Populated?... By Edwin Lincoln Moseley
Africa's First National Park ... By Mary L, Jobe Akeley

Features
Industry Looks To The Chemist... By D. H. Killeffer
How Stable Is The Earth's Crust?... By Hartan T. Station
Milk As A Control For Rickets.... By James A Tobe
Forest Conservation And False Alarms.. By Wilson Compton