Page:Popular Science Monthly Volume 89.djvu/13

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IXDKX TO VOIJME 80

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Cardboard Tubes 275

How a Compact Molded Condenser Is Built 275

Primary Regulator for the Induction Coil 275

Small Radio Stations 275

Lowering t^e Decrement 277

Lighting Audion Bulbs Cheaply 276

Music by Wireless 278

A Substitute for An Aerial 280

Telephone Headbands 280

A Built-Up Wireless Mast 281

A Sending Condenser 282

Adjusting Handles 283

A New Detector Material 284

A Good Loose-Coupler Switch 285

Modified Audion Is New Telephone 285

Reducing Arcing at Key Contacts 285

A Quencned Gap with Metal Spacers 286

Switch Points for Radio Instruments 286

What Radio Readers Want to Know 287

A Microphonic Amplifier 437-

Constructing an Amateur's Aerial 439

Guying the Mast 442

A New Tuner Arrangement 445

Lepel Improves His System 445

A New Variable Condenser . . .• 448

The Quenched Gap 448

A Kick-Back Preventer 448

How to Become a Wireless Operator 449

Curious Form of Dustproof Detector Cup 452

A Rotary Adjustment for Coupling 452

What Radio Readers Want to Know 453

Insulating the Ground Connection in Radio Work 613 An Easily Made Self-Locking Device for Barn-

Doors 614

Converting a Plain Zinc-Gap into an Air Blast

Spark-Gap 62 I

Strengthening the Static Field of an Amplifier. . . , 622 Overcoming Troubles in a 200-Mcter Wave Outfit 623

How to Become a Wireless Operator 627

Employing Kites to Support an Aerial 630

A New Spark-Gap for Wireless Telephony 63 I

Making a Crystal Detector from Cheap Materials 633 Wireless Telegraph Stations in the West Indies . . 633 I ns'ilating and Decorative Enamel for Electro- Magnets 634

Best Wavelengths for Certain Distances 635

What Radio Readers Want to Know 636-637

Converting a Freight Car into a Wireless Station. 639

The Construction of a One-Mile Receiver 789

How to Become a Wireless Operator 789

Making an Inductance Switch for Radio Work. . . 796

What Radio Readers Want to Know 797

Simple Method of Remagnetizing Magnets 799

The Telephone Receiver for Wireless Apparatus. . 799 Experiments with Antennas of Varying Lengths. . 800 Making the Aeroplane Generate Its Own Power

for Wireless 842

Using a Tree as a Mast for a Wireless Station .... 871

Making an Emergency Aerial for Wireless 948

How to Become a Wireless Operator 949

Transformer Trouble in Radio Transmitting

Apparatus 954

Practicing the Code Without Using a Buzzer 955

How to Take Up the Slack on Your Aerial Wires. 955 Canada to Protect Her Parks with Radio Service. 955 Preventing Interference of Signals by Amplifying. 956 A New Direct-Current Transmitter in Radio

Communication 957

What Radio Readers Want to Know 958

RAILWAYS

End-Door Automobile Express Cars 7

Driving Railway Spikes with a Motor-Car 26

Hairpin Curves on a Mountain Trolley Line 48

Beautifying- Manhattan's Riverfront 86

Minute Men of the Rails 169

Boy's Road Wagon Is u Real Locomotive 183

An Auto Mountain Railway 207

A Western Railroad's Clay Locomotives 242

A Railroad Which Fights Its Own Fires 251

The Senators' Subway 328

A Locomotive that Burns Pulverized Coal 376

Feeling the Way 379

Railroad Treads for Motor-Trucks 391

Stopping Trains Automatically 433

Odd Uses for Railroad Cars 500-501

Solving New York's Freight Problem 546

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Ten Millions to Save Four Miles 553

A Danger Signal Which Compels Attention 572

Our First Armored Car 588

The Hose Is Mightier Than the Brush 688

A Motor-Wheel for the Railroad Velocipede 742

A Locomotive Side-Frame Which Weighs Nearly.

Seven Tons 829

A Wind- Deflecting Lookout Mask for Engineers. . 832

Daylight Lamp Signals 847

A Device for Adjusting the Ends of Steel Rails. . . 915 Transforming a Railroad Water-Tank Into a

Home for Two 919

SHIPS AND SHIP BUILDING

Protecting a Battleship with a Belt of Air 18

How a Steamer's Engine Room Is Ventilated .... 104

Charting the Dangers of the Deep 204

Coaling a Liner with An Elevator 206

The World's Largest Ships' Register 226

Pulverized Coal Burners on Our Modern Ocean

Steamships 230

A Damaged Lock Gate Repaired by I ts Own

Water 234

A Venetian Barge in Boston 258

A Guard for Mooring Ropes to Prevent Rats from

Landing 363

Tethering the Largest of the Super-Dreadnoughts 381 Milazzo — the Largest Coal Ship in the World. . . 392

Cooling a Ship's Laundry 477

Pocket-Flashlight Distress-Signals 520

Piping Oil to Ships at Sea 521

A Fog-Stick for Traffic on the Great Lakes 522

A Fleet of Indoor Battleships 578

Detecting Enemy Submarines from a Ship's Look-

Out 579

Preventing Ships from Rolling with Fly Wheels . . 592

The Thousand-Foot Battleship 670

A Novel Device for Generating Fresh Air in Sub- marines 681

Telegraphing Through the Ocean 711

Defending America with Motor Torpedo Boats. . . 721

Miniature Magnet-Propelled Ships 737

Discovering Contraband of War 752

An Endless-Chain Barge Loader 845

She Lies on Her Side— But They'll Raise Her 880

SPORTS AND PASTIMES

Doing Without the Caddy 12

Golfing at Home 13

Playing Baseball by Machine 57

The Five-Wheeled Velocipede 64

What Ho! The Jitney Yacht 83

A "Jackomobile" for Two 100

What Inventors Are Doing for the Fisherman . . . 105

Camp Fire Maxims ....T 115

Kite Making at Home — II 127

How to Make a Practical Gas-Range Lighter .... 156

Weightmobile Approaches Perpetual Motion 158

Leaping Horses That Are Unafraid 168

Another Baseball Game in Disguise I 74

An Air-Tight Compartment for Canoe Campers. . 184

Turning Your Racket Press Into a Camp Stool . . . 224

The Latest in Golf Clubs 246

"Canal Boats" Which Are Real Water-Shoes... 257

The First Bird House Ejthibit 260

Making a Bomb Thrower for Sham Battles 295

The Whistling Bicycle Wheel 297

How to Make a Toy Zeppelin 313

Ferreting out the Secrets of the Golf Ball 324

A Metal Disk Supplants the Golfer's Tee 324

Golfing by the Clock — a New Idea for Golf Courses 325

What Golfing Sometimes Does to the Feet 325

Making Your Head Behave While You Hit the Ball 325

A Paddleless Canoe Propelled by Feet and Hands 326

Mechanical Joys of Coney Island 394

Playing Checkers on the Lawn 398

Good-By to the Pin-Boys in the Bowling- Alley . . . 409

Battle Ball— a New Sport 420

Getting Ready for the Clay Birds 421

A Fascinating Old Sport in a New Dress 436

The Trench Marble Game and How It Is Played. . 455

Decoy Ducks That Quack and Swim 509

The Old Fondness for Cycling Is Coming Back. . . 514

Hunting the Mud Pigeon 530

Bucking a Wooden Football Line 554

Playing Ball with a Revolving Fan as a Target . . 568

Motoring on Rollcr-Skates 569

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