With the Editors, December 1921

Prehistoric Sculpture

An Account of the Discovery of Two Bisons Sculptured in Clay by the Cro-Magnons of 25,000 Years Ago

The Role of Research

Creating New Things and Revising Old Things for the Industrial World

America's First Model Airway

Britain's New Battle Cruisers

Railways of the World

Comparison of the Mileage, Equipment, Working Force and Total Investment of the Eight Leading Railroad Systems

Science in Safe-Breaking

How Modern Technology Works For and Against the Yeggman

The 4000-Pound Demolition Bomb

A Means for Detonating 2000 Pounds of T.N.T. on a Selected Target

Leading Armies of the World

Comparison of the Active Armies, Trained Reserves, Available Manpower and Field Artillery of the Five Leading Powers

High-Speed Fighting Ships

The New Army Sixteen-Inch Gun

Exhibition Firing of the Most Powerful Coast Defense Gun in Existence

Seats for 125,000

Oakland's Giant Stadium, Cut Out of the Center of a Mountain

Stainless Iron--A New and Striking Product

Our Point of View, December 1921

Abraham Lincoln and the Repeating Rifle

How an Inventor's Struggle for Recognition Was Assisted by the Action of the President

News and Music from the Air

What the Radio Telephone Means to the Farmer and Business Man at Home and at Work

The Mechanics of Ordnance Figures

Our Reforestation Activities

Some Facts and Figures About Tree Planting on a Gigantic, Yet Still Insufficient, Scale

Phosphorus, the Backbone of Life

America's Great Deposits of This Chemical for Fertilizers and Through Them for Food

Why Weary Metal Fails under Light Loads

The Causes of Steel Fatigue, and the Ticklish Problem of Testing Against It

The Revival of the Monoplane

Reasons Why This Type, Once Replaced by the Biplane, Has Again Become the Favorite

Difference Between Molds and Wood Destroyers

The Mechanism of the Pipe Organ

What Happens When the Player Passes His Fingers Over the Keys

The Oil and Albumen Content of Seeds

A Study of the Conditions Under Which the Seeds of Oil-Bearing and Textile-Producing Plants Give Their Highest Yields

Engineering in Truck Tire Building

Designs Which Decrease Wear, Prevent Slipping and Increase the Economy of Truck Operation

Restoring Sight to Blind Animals

The Banana and Its Uses

Getting Acquainted with This Tropical Fruit of Which There are Over Seventy Varieties

Recent Studies of the Venomous Snakes

New Light on Their Behavior in Attack and Defense, and on the Chemistry of Their Venom

Crossing San Francisco Bay by Bridge, Fill and Tunnel

Engineers Propose a Six-Mile Vehicular and Railroad Structure Joining San Francisco and Oakland, California

Fire Tests of Building Columns, Freak Boiler Explosion with a Man Inside

How Marine Worms Catch Their Prey

A Study of These Interesting Forms of Sea Life, Which Abound in Great Numbers and Wide Variety

A Map's Other Name is Ananias

The Various Projections Used in Representing the Earth's Surface, and What They Do to the Facts

Rock Crystal Balls, Acetylene as Auto Motor Fuel

Curator of Mineralogy, American Museum of Natural History

A Wilderness Industry

How Gold Is Extracted Out of Ores on a Huge Scale in Order to Make It a Profitable Business

Keeping Growing Potatoes Cool

The Story of Sugar

Where the World's Supply Comes From, and How It Is Converted from the Raw Material

The Self-Supporting College

Moss Scrubber for Irrigation Projects, How More Light Speeds up Vision, and more

A Climax in Concrete Construction

Erecting An Eighteen Story Reinforced Concrete Building at a Lower Cost Than a Structural Steel Type

The Camera Turned Sculptor, Static and Gasoline Fires

Eliakim Hastings Moore, Zirconium, the "Mystery Metal"