Page
A Machine for Cleaning Ceilings 84 1
An Unusually Intelligent Slot Machine 842
Mechanical Kinks 876—877
The Giant Destroyer of the Future 897
MEDICINE, SURGERY AND HYGIENE
What X-Rayg Can Do for Your Teeth 20
Killing Vermin with Gas 119
Eradication of Weeds Will Prevent Hay-Fever. . , 238
Chinese Doctors and Their Ways 243
War Will Diminish Stature and Vigor of Human
Race 252
If Your Hand Is Too Small— Stretch It 361
Exterminating Mosquitoes 367
The Latest Answer to "What Is a Cold?" 374
Fighting Infantile Paralysis 399
Taking a Census of Occupational Diseases 486
A Mechanical Masseur That Works Off Fat 486
Have You Perchance a "Vocational Disease?" ... 519
Where Beautiful Hair Is Not a Crowning Glory. . 528 Eliminating One of the Tortures of the Dentist's
Chair 534
How Do You Sit? 551
Sampling the Drinks for an Entire Large City . . 556
Steam Yourself and Drive Away Your Ills 575
Testing the Air-Fighter's Nerve 580
Mechanical Lungs for the Fire-Fighter 587
Some Peculiarities of Eye-Glasses 616
More Light on the Occupant of the Dentist's Chair 626
A Simple Electrical Device for Purifying Water. . 638
Exercising Machines for Wounded Soldiers 633
A Humane Method of Destroying Horses 684
New Apparatus for Setting Broken Limbs 684
Using the X-Ray on Animals 696
Defense for the Ears Against Noise and Shock. . . 707
Resuscitating the Drowned 744
Lifting Invalids with a Minimum of Discomfort. . 746
Why Do We Grow Bald? 812
New Cures at the Royal Baths in England 818
Making Air Fit to Breathe 833
Medicinal Cartridge-Beit for Peaceful Expeditions 849 A Device Invented by a Blind Doctor to Enable
Himself to Write Letters 849
Humanity's Bent Twigs 850
Corns — What They Are and Why They Hurt. . . . 857
The Medicinal and Hygienic Virtues of the Lemon 863
The Cancer Problem 873
Friction Tape Used for Plaster Strips 925
MINING
Steaming Frozen Ground for Gold 687
Coal-Mine Fatalities in the United States During
the Year 1915 696
NATURAL SCIENCE
How Fish Jump 1 00-Foot Dams 364
Borrowing the Night Lamps of the Fireflies 365
Why Whiskers Continue to Be in Style for Cats. . 369
Fishing in Guiana with the Bow and Arrow 385
When Manicuring Nails Is a Dangerous Job 410
Rocking Stones and Their Romantic Story 413
Even the Hornets Have New Ideas Sometimes, . . 417 Exploiting the Island of Laysan for the Eggs of the
Albatross 428-429
The Reason Why We Have Two Eyes 434
Insect Grotesques 496-497
When Nature Plays the Architect 498-499
Freak Trees. How Did They Happen? . 512
A Curious Egg Shaped Like a Dumb-Bell 513
A Slab of Sandstone Seventy-Five Million Years
Old /. 513
Would You Recognize the Ear-Bone of a Whale If
You Saw One? 513
Why the Color of Sen Water Is Blue or Green. . . 522
Crossing Dangerous Rivers with Goatskin Floats . 528
A Mat^ician Among the FishcB 562
The Strange Vegetable Sheep of Peru 563
Why You Hear Well on a Clear. Frosty Night . 646 Weather Bureau Duties Overlooked in Criticising
the Weather Prophet 647
The Tree Warfare Against Rocks 650
The Traveler's Tree 651
A Fish That Builds a Nest Like a Bird , 654
��Page
When Rain, Thunder and Lightning Start Toward
the Earth at the Same Time 674
The Deepest Known Place in the Ocean 683
Nature and Not Cannons the Cause of Rainfall. . , 744
Queer Denizens of the Deep 822
Is This the Origin of Forcible Feeding? 823
As a Packer Let Us Recommend Mother Nature . . 826
Not Candy but Moth and Butterfly Eggs 827
Iridescent Fish-Eggs for Table Decoration 875
"Great Fleas Have Little Fleas Upon Their Backs
to Bite 'Em " 875
Why Does Sap Rise Against Gravity? 886
PHOTOGRAPHY AND MOTION-PICTURES
As Easily Handled as a Rifle , 77
Seeing the Unseen 89
Photography in Natural Colors 102
A Dark-Room Lamp I 20
How to Photograph Wild Animals. 136
Catastrophes by the Foot 163
Comic Insect Photography 191
A Photographic Eye for the Airman 202
Washington Monument as a Motion-Picture Screen 354
Staging the Celluloid Thriller 401
An X-Ray Tilting Table 407
"Shooting" a Photograph with a Pistol-Camera 408
Pendulum for the Dark Room 4bO
An Improvised Reflecting-Camera 460
Novel Device for Copying Pictures 460
Home-Made Camera Shutter 461
A Useful Trimming Board 461
Simple Test of Shutter Speed 461
Cheap Photographic Changing Box 473
Wild Animals That Photograph Themselves 483
Preserving the Orchestra Leader's Art 535
Drying Negatives by Heat from a Kerosene Lamp 602 A Photographic Printing-Box for Use with Electric
Current 603
Saving the Picture Show with a New Rheostat . . . 633
Using the X-Ray on Animals 696
A Daylight Developing-Tank . 716
Boring Straight by Photography 720
Making the Music Fit the Movie 733
"Shooting" Birds with a Camera ' 741
Eight Pictures on One Plate 856
Photographic Printing Masks Easily Made 931
A Dark-Room Lamp to Be Used Under a Glass
Tray 934
PICTURE PAGES
A Tree Like the Rock Which Moses Smote 651
Exercising Machines for Wounded Soldiers 653
A Fish that Builds a Nest Like a Bird 654
The Great Hoodoo Temple 655
Where Germany Gets Her Basalt Paving Blocks. . 656
Relics of Indian Superstition 658
Curious Clocks of Paris 659
A Great Collapsible Field Periscope 660
Watching a Battle Through a Super-Periscope. . . 661
The Largest Duck Farm in the World 662-663
Let a Puff of Air Do It 664
Air Is Stronger Than Human Arms 665
A Modern "Newspaper Maker" 676
Using the Telephone on the Rifle Range 682
Scenes in Alaska 814 — 815
Marooned by the Tide at West Australia 816
Trapshooting in the Navy 817
New Cures at the Royal Baths in England 8l8
Tropical "Snow Drifts" of Cheesecloth 819
Food Freaks 820—82 I
Queer Denizens of the Deep 822
Is This the Origin of Forcible Feeding? 823
Fighting Weapons of Seven Warring Powers.... 824
Aeroplane Art of To-day 825
As a Packer Let Us Recommend Mother Nature. . 826
Not Candy but Moth and Butterfly Eggs 827
Japanese Ivory Carvers Use Modern Tools 828
PRACTICAL WORKERS DEPARTMENT
How to Make an Efficient Boiler-Patch 117
An Easily Made Mercurial Barometer I 18
A Handy One-Drop Oiler I 20
A Non-Spillable Funnel 120
Rubbing in the Lathe 120
An All-Steel Screwdriver 121
A Buck-Saw Attachment 121
�� �
