INDEX TO VOLUME 91 



Page 

 Why a Sidewalk Was Built on the Top of a Storm- 

 Sewer Tunnel 746 



Building a Park Around the Debris of a Burned- 

 Down Schoolhouse 722 



Two Billion Paving Bricks a Year 855 



Measuring the Flow of Rivers 867 



ELECTRICITY 



Electrified Street Directions 33 



An Effective Burglar Alarm 49 



Cooling a Room with Cold Water 62 



An Electric Machine for Cutting Uniforms 71 



Newspapers in the Sky 104 



A Telephone Attachment Which Performs the Ser- 

 vices of a Watch Dog . . . . 105 



Seal Your Letters by Electricity 114 



Applying Insulation to Splices Made in Electric 



Wires 147 



A Simple and Easily Made Electric Battery Motor 147 



Rebuilding Worn-Out Dry Battery Cells. 148 



Method of Insulating Secondary "Pies" in Trans- 

 formers 1 49 



Steadying Voltage of Dynamo Driven by Gasoline 



Engine 150 



Increasing the Voltage of a Dry Battery 150 



Keyless Lamp Socket for Switching Electric Cur- 

 rents , 151 



The Effect of Electricity and Music on the Human 



Organism 152 



A Rain Alarm Made of a Broken Electric Globe . . 152 

 Protect Yourself Against Highwaymen with an 



Electrified Cane 191 



An Electric, Self- Winding Clock 222 



A Light for Luring Fish 233 



The First Life-Long Flashlight 240 



A Flashlight Attached to Your Razor 251 



An Electric Cord for the Sash Curtain 280 



Simple Oscillograph to Record Current Alternations 284 

 Reversing Rheostat for Controlling a Small Motor 309 



A Drip-Pan Alarm for the Ice-Box Drain. 311 



The Electric Stevedore 328 



Telephoning from a Trolley-Car 353 



The Ben Franklins of Today 363 



The Electric Manicurist 400 



Increasing England's Crops by Electricity 421 



The Price of This Kiss Was Death 432 



A Method for Recharging Dry Cells 442 



His Lighting Bill Is Twenty-five Cents a Month. . 536 

 "Do It Electrically" Also Applies to the Barber. . 538 

 Using Resistance in Field Wiring on Automobile 



Dynamo 606 



Connecting a Spot Light in an Automobile Dynamo 



Circuit 613 



Electric Lamp Attached to a Spoon for Tongue 



Depresser 618 



This Electric Heating Faucet Has No Switch or Coils 668 

 An Electric Wire in the Street Ignites a Balloon. . 670 

 Using an Electric Heater to Dry the Glue on En- 

 velopes 672 



Announcing the Election Returns by Telephone . . 740 

 Making Telephones and Phonographs Clearer.... 745 

 Click! Click! Go These Electrically Operated 



Scissors 748 



Telegraphing by Typewriter 756 



Automatic Cut-Outs for Charging Storage Cells . . 789 



A Practical Electric Vacuum Cleaner 791 



Making an Electric Furnace for the Laboratory . . 792 

 Testing Electric Wires for High Tension Currents . 797 

 Resistance in Circuit to Make Double Tone Auto- 

 mobile Horn 797 



Making a Selenium Cell for the Laboratory 799 



A New Way of Oiling Machinery by Electiicity. . 825 



Illuminated Muffs 881 



Combining an Electric-Elevator with the Shoe- 

 Shining Chair 888 



Applying the Principle of the Phonograph to the 



Telegraph Sounder 889 



Reducing Packing Costs in Handling Telephone Sets 908 

 A Telephone Conversation May Be Almost "Pri- 

 vate" Nowadays 913 



Telephone Conversation Made Easy by a New De- 

 vice 919 



Charging Storage Batteries with Direct Current . . 947 



Simple Method of Making Storage Cells 947 



Auto-Transformer in Headlight Circuit on a Mag- 

 neto 952 



Page 



Making a Good Outdoor Ground to a Pipe 952 



Finding the Combined Value in Parallel Resistances 959 

 Heating a Soldering Iron with an Electric Arc. . . . 960 



HOUSEKEEPING MADE EASY 



Save Your Bottles. A Shortage of Jars and Cans 



Is Threatened 37 



Not Even the Space Underneath This Desk Is 



Wasted 37 



A Machine for Ironing Stockings 49 



Household Appliances 52-53 



A Tea-Making Machine 66 



Using Your Player Piano as a Vacuum Cleaner. . . 72 

 Changing the Apartment Telephone into a Pay- 

 When- You-Call System 86 



Alarm Which Tells You When Your Bathtub Has 



Been Filled to Whatever Depth You Desire ... 87 

 Combining a Strainer with the Bung of a Barrel . . 90 

 Making the Kitchen Range One Hundred Per Cent 



Efficient Ill 



A Clever Bottle-Opener 1 90 



Co-operative Kitchens to Solve the "High Cost" 



Problems 198 



Children May Write on" These Walls Without Fear 



of Punishment 204 



An Electric Fan Runs Without Electricity 217 



Household Appliances 238-239 



Keeping Out Flies When You Open the Door. . . . 260 

 Household Bookless Bookkeeping on the Poker- 

 Chip Principle 267 



Put Your Flowers Outdoors on this Adjustable 



Window Shelf 271 



Hanging Backing Cloth for Wall Paper 283 



A Double Deck Revolving Clothes Hanger for a 



Yard 287 



Iceless Refrigerator Using Evaporation for Cooling 289 

 Sterilization Is the Essential Factor in Canning 



Vegetables 290 



The Burlap Cooler 351 



Scrub Your Walls by Machinery 360 



Housekeeping Made Easy 372 -3 



An Approved Smoker's Kit 410 



A New Attachment to Hold the Trousers in Place 420 



A Handy Clothes Closet for Your Vacation 424 



The Clam-Shell as a Decoration 43 5 



That Bit of Butter Left on Your Plate— What 



Becomes of It? 519 



This Vacuum Cleaner Is Used Like an Ordinary 



Broom 519 



Housekeeping Made Easy 552-553 



Fountain Spot-Remover Works Like a Scrubbing 



Brush 568 



An Owl with Eyes of Scissors and Backbone of Paste 576 

 You Can Roll This Can Without Spilling the Gar- 

 bage , 593 



A Wooden Lighthouse Candlestick and How It Is 



Made. 600 



Sending the' Wash to the Laundry Through a Glass- 

 Lined Chute 664 



The Full Dinner Pail 669 



An Accommodating Gas Stove 670 



What to Do with That Dripping Umbrella 671 



Keeping Your Neckties Smooth 672 



New Can-Opener Which Does Not Destroy the Can 679 



Housekeeping Made Easy 694-695 



A Necktie Rack 702 



Cook Over the Gas Lamp 72 I 



Making a Window Seat Out of the Radiator 725 



Dry Your Fruits and Vegetables at Home 736 



Carry Your House Key in Its Own Bag ........ 736 



The Kitchen Cabinet Up-to-Date 742 



The Temperature Alarm 747 



Keeping the Shampooing Soap Suds Out of Your 



Eyes 804 



Storing Needles and Thread in the Handles of 



Scissors 828 



Solving Kitchen Problems Electrically 830 



Abolishing the Garbage Can 833 



Rocking the Baby Fore and Aft ... 842 



New Shoe-Polishing Kit 857 



Improved Office Appliances 870 



Electric Fish-Sealer 873 



Baby's Wheeled Dressing Table 877 



Housekeeping Made Easy 890-91 



A Pelican in Your Wardrobe to Hold Your Coat. . 904 

 Want to Go to the Attic? Just Pull Down the Stairs 912 



