Page:Popular Science Monthly Volume 91.djvu/14

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Hand Bob-Sleds Made of Barrel Staves 934

Making Butt Mortises with an Ordinary Rabbet

Plane 934

Making a Talking Machine Stylus from a Tooth- pick 934

Making a Whistling Weather Vane for the Barn . . 934

Windng a Coil Spring Evenly 934

Cutting Rafters for Gothic Roof Barn Construction 935 Fruit Jar Rubber Ring to Repair Bicycle Tire

Puncture 935

The Proper Care of a Soldier's Wardrobe 935

Improving the Qualities of Cheap Lead Pencils... 936

A Barrel Stave Iceboat 937

A Homemade Sight Feed Oil Indicator for an Auto- mobile 938

A Simple Method of Fastening Umbrella Handles 938

Simple Designs for Sheet Metal Working. . 939

Garden Hose Used as a Form for Cement Pipe. . . 941

Eliminating Noise from Shift Levers 941

Repairing a Scratch on an Automobile 941

How to Straighten a Warped Drawing Board. . . . 942 Making a High Gloss Finish on a Matt Surface

Picture 942

Protecting Drawings on Drawing Board 942

Setting a Lathe Quickly for Taper Turning 942

Teeth of a Hack-Saw Blade Used for Spacing on

Section Liner , 946

How to Make a Secure Joint in Copper Tubing. . . 948 Things to Know About Lubricants for Machinery . 948 Constructing a Thermostat to Regulate Furnace 953 A Coating to Make a Battery-Box Acid Proof .... 954 Heating Sheet Hard Rubber to Cut Round Disks . . 959 Lighting the Dash-Board of an Auto from the Side

Light 960

Sheet Asbestos to Make a Packing for Steam Chests 960


"Silent Music" — Recreation for the Bedridden. . . 28 Curious Circuit for Audion on a Wireless Set. ... 151

Conversion of Kilometers to Nautical Miles 151

An Experimental Wireless Aerial Made of Zither

Strings 151

To Prevent the Ears Perspiring When Wearing

Telephones 152

Mounting Tinfoil on Glass Condenser Plates 152

How Germany's Secret Service Wireless Stations

Are Being Weeded Out 1 53

A Crystal Detector Holder for Wireless Apparatus 155 Effect of the Moon and Season on Wireless in the

Tropics 1 55

A Trussed Aerial Spreader for Long Wires 1 56

Position of Wireless Waves Passing Over Land. . . 156 Cloudy Days Best for Wireless Wave Signals .... 1 56 Improving the Tone of a Test Buzzer Used on Wire- less Detector 1 56

Simple Construction of a Rotary Gap Disk 1 56

Simple Solutions of Wireless Problems 157

Magnetic Brake for a Wireless Rotary Gap 160

Adjusting the Detector of a Receiving Set 160

How theJGovernment Seals Unofficial Stations . . 208 A Simple Arc Lamp Using a Thermostat Control . . 308

Slow Acting or Sluggish Relays 308

An Ingenious Wiring System for Two Inductive

Transformers 310

A Variable Condenser for a Receiving Set 310

An Amplifying Electrostatic Radio Receiver 311

Treating Cardboard Tubes for Tuners 311

Strong Wireless Signals in Winter Time 312

A Testing Set That Does Not Use a Battery .... 312 How the Radio Inspectors Trapped a Disorderly

Amateur 313

How to Make a Kick-Back Preventer for Wireless

Apparatus 314

A Use for Discarded Cylindrical Food Boxes 314

Variable Primary Coil Using a Switch Instead of a

Slider 314

America's New Semi- Wireless System for Telephon- ing from Captive Balloons 315

A Polarity-Changer for Reversing Lighting Battery

Current 315

Dormitory Beds Furnish the Essential for Antennas 3 1 6

An Insulation for Secondary Terminals 316

Wireless Work in Wartime 317

A Simple Fixed Adjustment Detector 320 ,

An Audion Battery Made of Medicine Vials 441

An Easily Adjusted Detector-Stand 441


Wireless Signals Transmitted by Telephone 442

Fighting the Big Guns with Wireless 443

Supplanting the School Bell with Wireless 445

How to Make a Variable Condenser for Five Cents 446

Wireless Work in Wartime 447

An Inexpensive and Quickly Made Detector 450

Relieving the Strains on Aerials 450

Sustained Wave Telegraphy Between the United

States and Germany 451

Double Set of Receivers for Visitors 453

A High Voltage Lead-in Insulator Tube 453

Loading Coil in Series with the Secondary 453

A Ticker Interrupter Made from a Buzzer 454

A Simple and Attractive Loading Coil 601

Transmitting Wireless Messages Underground

Without Aerial 602

Sending Wireless Messages Under Fire 603

Construction of a Rotating Arm for a Rotary Gap 606

Wireless Work in Wartime 607

A Grid Placed in the Wings of an Airplane 614

I ncreasing the Efficiency of the One-I nch Spark Coil 787

Wireless Work in Wartime 793

A Strong Guy- Wire Anchor for Aerial Poles 797

A Magnetic Telegraph Key for the Wireless Operator 798 Ballast Weights for Antenna to Prevent Aerial from

Overturning 800

The Marconi Company Sues the Government .... 913

Detecting Defective Insulators 914

The Human Morse Code 950

An Inexpensive Multi-Point Loading Coil 953

Water Glass Gage for a Lead-in Insulator 954

Wireless Work in Wartime 955

An Easily Constructed High Tension Insulator. . . 959


This Railroad Crossing Cleans Itself and Eliminates

Jolts 5

Attacking Mail-Car Robbers with Deadly Fumes. 27 Owens Valley, California, Has a Freight-Car Hotel 87

Can the Railway Train Be Made Noiseless? 92

Flushing Streets with Water Pipes on Trolley Cars 107

Street Railway Smoking Car 214

The Largest Traveling Kitchen 224

The Biggest Locomotive 251

A Refrigerator Car That Really Works 394

The Most Powerful Locomotive in the World .... 396

Street Cars Pull Each Other Up , . 41 I

A Sanitary Dining Car 418

Solving the Car Shortage Problem 422

Lest the Engineer Forget 436

Canning the Baby in a Super Sleeper 513

How Print Butter Is Shipped to the Retailer 519

Flagman's Shelter House Built Like a Mosque. . . 551 Safeguarding Our Bridge and Railroad Crossings . . 565 Putting Driving Wheels Under the Locomotive

Tender 570

A Lift Deck for Automobile Freight Cars 592

A Lumberman's Camp Which Can Be Moved from

Place to Place on Rails 598

Special Cars for Persons Carrying Parcels 708

Loading Cattle on Trains in a New Way 723

Diminutive Electric Locomotives 738

How a Railroad Steam-Shovel Traveled Through

New York City 747

An Iron "Flag" for Protecting the Railroad Car

Inspector Against Injury. 755

Keeping the Trains from Being Blown Off the

Tracks 824

A One-Man Rail Grinder 825

A Labor-Saving Dump Car 884


Why You Can't Compare Ships in Tons 29

A New Life-Boat 60

Salvaging in Armor 93

Motor Attachment Which Prevents the Rowboat

Propeller from Being Injured 96

The Latest Salvaging Device — An Electromagnet . 113 An Electric Eye Watches the Smoke Screen During

a Battle 115

Practical Motor-Boating 116

A Two-Million-Dollar Hospital Ship 206

A Ship with Six Hulls 209

The U.S.S. "Recruit" 212

New Type of Life Boat 223

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