Modern Methods for Exterminating the Mosquito Pest
Threshing by Night Under Electric Light
Uncle Sam Says Miraculous Wheats Are an Old Delusion
Where the Modern Farmer Spends His Evenings
Leaping Horses That Are Unafraid
TO paraphrase the words of a wellknown humorist, there is motionpicture realism and, on the other hand, there is motion-picture realism. There is cinema realism which consists mainly in cheap and unconvincing illusions. Into this class falls the director who substitutes a miniature dreadnought in a bathtub for the real article, or the director who mounts his camera on a rolling platform, this device giving to the steady deck of a ship the appearance of rolling and tossing.
Perfuming and Cooling the Air with an Electric Fan
Why the Gasoline Engine Keeps the Farmer Boy at Home
Modem Dog-Catchers Use Motor Trucks and Wire Nets
The Cockroach Attracts Attention as a Trouble Maker
The King of New York’s Lighting Spectacles
Origin of Gas Jets Traced to Woman’s Thimble
Extinguishing an Oil Fire with Carbon-Dioxide Foam
Locating Guns by Delicate Earthquake-Detectors
Throwing a Line of Communications Across a River
Blow-Pipes of the Borneo Land Dyaks
WRECKING-TRAINS are located on every division of important railroads, standing idle in the yard, waiting for calamity. A crane-car, with sufficient power to lift a freight-car as a child lifts a toy; a supply-car, containing rope, cables, chains, jacks, crow-bars, tools, lanterns, fire apparatus, dynamite, rails, ties; a caboose for the wreckingcrew.
The Reinforced Concrete Principle Applied to Automobile Tires
Boy’s Road Wagon is a Real Locomotive
A Cane to Help the Convalescent Soldier
Wind Cave Excels Mammoth Cave
At Last ! a Machine Which Irons Skirts Without a Murmur
Soldier of Today Better Off Amid New Horrors
An Air-Tight Compartment for Canoe Campers
Accelerating the Fruit - Picker Accelerating the Fruit-Picker with a Picking Harness
A Deep-Sea Fish Which Has a Lantern of Its Own
A Sailor’s Nautical Wind-Wheel
What the Great Army of Inventors Are Doing to Make this a Horseless Age
What’s New in Automobiles and in Their Accessories
SKIPPERS sleep peacefully in their berths on the freighters lying in the Thames near London in spite of submarine warfare. Freight from America and other countries, munitions of war and food supplies, arrive there in such quantities that the boats cannot be unloaded immediately, but they are just as safe in the mouth of the Thames as they would be in New York harbor.
CERTAIN writers, chiefly Dean Swift and his followers, have taken pains to impress upon their readers the fact that if they had microscopical eyes, all beauty would disappear. The most delicate skin viewed by such eyes would be rough and repulsive ; the whole world would be filled with disagreeable sights.
A Tool for Buffing, Drilling and Grinding Metal Surfaces
Pneumatic Gun with a Dynamite Shell
What a Little Electric Motor Can Do
ONE of the most interesting of all photographic diversions is the making of comic insect pictures. Success in this class of work requires a suitable camera, good taste ‘and judgment in composition, and an unlimited amount of patience and perseverance.
Machines That Smoke Cigars The Modern Way of Sampling Tobacco Leaf
Rocks Composed of Diatom Earth Which Float
A Mud Mosaic in the Wake of the Treacherous Colorado
HEREWITH iS shown a trap for catching the English sparrow which is one hundred per cent efficient, if properly operated. It is made of tinned wire, electrically welded, strong and durable. The size of the trap is thirtysix by eighteen by twelve inches, and weighs twenty-five pounds.
TO make a successful fight against the ever-moving sand dunes of the Columbia River region and at other places along the Pacific Coast, the United States must follow the plan adopted by France many years ago. It must build one great dune in an effort to eliminate many smaller ones.
GREATER progress has been made in aerial photography during the present war than in the years following 1858, when M. Nadar, of Paris, took a view of that city by means of a camera attached to the basket of a balloon. The fact that a photograph from an aeroplane of fortifications, damaged railways, bodies of troops, and the contour of the enemy’s country gives valuable information which is absolutely reliable, not being dependent for its accuracy on the skill and coolness of the observer, makes this form of reconnaissance of the highest military importance.
LAST summer a submerged rock was found at the entrance to Boston harbor, close to which one or more of our tenmillion-dollar super-dreadnoughts had repeatedly passed under the supposition that the water was forty-five feet deep, whereas it was actually only twenty-three feet deep.
SPEED and certainty are the two principals upon which the great steamships which ply between continents are operated. They are permitted only a limited number of days in port; they must be swiftly unloaded and cleaned ; and they must be no less swiftly loaded, and made ready for sea.
Exhibiting Our Army’s Efficiency át the War Maneuvers at Sheepshead Bay, New York
Turning Your Racket-Press Into a Camp Stool
An Old Lamp Used by Rubber Gatherers in Brazilian Jungles
Where Freckles Come From and Why They Stay
FOR the transportation of passengers up Mount Tamalpais in California a number of automobile railway cars of unique design have been devised. The cars are propelled by a sixty-horsepower, water-cooled engine, and there is room in the spacious tonneau for twenty people, in addition to the driver.
The World’s Largest Ship’s Register Chiseled in Rock
Firing with Heavy Artillery at an. Enemy You Can’t See
MANY attempts have been made to construct an instrument that would successfully reproduce at the same time phonograph and piano music. Edwin S. Votey of New Jersey has taken out patents on an instrument which he believes meets all requirements.
A Submarine Blockade Runner Which Could Carry $1,000,000 Worth of Chemicals
A Stepladder with an Ambition to Adapt Itself
Pulverized-Coal Burners on Our Modern Steamships
Moving Guns with an Electric BatteryCrane -Truck
Surviving Horse-Car Lines in the United States
Why Some Girls Don’t Leave Home
From Kitchen Drudge to Household Mechanic
Coal-Dust “Mountains” are Now Repositories of Wealth
A Damaged Lock-Gate Repaired by Its Own Water
THANKS to the control of the North Sea by the British fleet, the entire manufacturing world has been forced to realize its dependence upon Germany for many materials. Some coal-tar drugs, dyes, and the like are worth anywhere from ten dollars to one hundred dollars an ounce; others cannot be obtained at any price.
How Pittsburgh Has Solved Its Most Irksome Problem
Eradication of Weeds Will Prevent Hay-Fever
Protecting Jewelry Store Windows With a Burglar-Proof Curtain
The Burglar-Proof Store-Window
Lowering a Bridge Without Blocking the Street Traffic
three-wheeled truck supplies the driving energy to the
more successful in an institution where, in an atmosphere of routine
Why a Grasshopper Is Like a Telephone Lineman
Hitting the Trail with a Wheel-Barrow and Determination
Automatic Flagmen to Warn MotorCar Drivers
A Western Railroad’s Clay Locomotives
TO all intents and purposes, Pittsburgh has solved its smoke problem. Although it is having a hard time living down the time-worn nickname of “the Smoky City,” the fact remains that as a result of the efforts of a municipal Bureau of Smoke Regulation, the “production and emission of smoke” in Pittsburgh has been abated fully seventy-five per cent within the past three years.
Keeping Cool with a Fan Driven by a Hot-Air Engine
The Latest in Golf Clubs
A New Safety Razor with a Lamp Attachment
How the Government Would Make Paper from New Woods
What Makes the Hair Suddenly Tum Gray?
Franz Otto Koch
THE native Chinese doctor is a curiosity. He passes no examination; he requires no qualifications; he may have failed in business and set up as a physician. In his new profession he requires little stock in trade, medical instruments being almost unknown.
Why You Can See Two Sides of a Thing at the Same Time
War will Diminish the Stature and Vigor of the Human Race
Plants on National Forest Ranges Which Kill Cattle
ELECTRICAL science has brought forth so many startling discoveries in the last decade or two that even the average person is rather proof against being astonished at anything. Almost incredible accomplishments of an inventor’s years óf unremitting labors are often dismissed with the faint praise that electricity is only in its infancy.
COMBINING the utility of both a gasoline and an electric automobile, a new dual-power passenger car recently put on the market by a western manufacturer, may be run by either gasoline or electricity, or both, thus retaining the great mileage ability of the gas car and at the same time the simplicity of the electric.
OF what use to man is this great army of hawks, harriers, and falcons we see or read about? There was a time when these “hawks” and their kind were simply regarded as fit subjects for the brush and pen of the professional ornithologist; for the scalpel of the taxidermist, or a legitimate target for every gunner in the land that came across them in the open.
ASTRANGE looking craft made its appearance recently on the Charles River. It was an exact replica of the state barge of Venice used annually by the doge in the ceremony of the marriage of the Adriatic. It led the procession in the water festival at the exercises when the transfer from the old to the new Massachusetts Institute of Technology buildings in Cambridge was made.
Building Houses for Birds—A New Countrywide Movement
IN the Puget Sound country the severest winter of the last quarter century has been productive of a new constructive work, acquaintanceship with, and love for birds. For the first time in its history Washington took a real interest in its songsters.
AN automobile engine is a heat engine. The gasoline is drawn into the cylinder in the form of vapor, which consists of about one part of gasoline to eighteen parts of air. The vapor, when it comes in contact with the electric spark, explodes, or, more properly stated, burns with flash-like rapidity.
A DETACHABLE pipe in which a specially prepared roll of tobacco is loaded in the stem instead of the bowl is said to afford a cool and non-biting smoke. Air is drawn in to the burning tobacco through the bowl, and as it is packed up tight against the stem nicotine cannot enter the smoker’s mouth.
OUR first Prize Contest, which was announced in the April, May and June issues of the POPULAR SCIENCE MONTHLY and which closed on June 15th, brought responses from all over the country. The first prize, of Twenty-five Dollars in money, has been awarded to Mr. K. B. Warner of Cairo, 111., for his article on “The Construction of an Amateur’s Aerial Mast.”
Practical Hints Wireless for the Amateur Communication
A Wireless Telegraph Transmitter with Two Spark Frequencies
A Booth for Long Distance Receiving
How a Compact Molded Condenser Is Built
Small Radio Stations
Primary Regulator for the Induction Coil
ORDINARILY a radio transmitter using a rotary gap sends out its signals on practically a constant spark frequency, and at the receiving station it is often possible to recognize a number of different sending stations by this characteristic alone.
Fig. 2. Proper position of the lugs on the cylinders
A Clever Window-Display
Lowering the Decrement
Music by Wireless
Lighting Audion Bulbs Cheaply
Five Examples of Alarm Work
A Substitute for an Aerial
THE good points of the Edison battery are great constancy, very low internal resistance and freedom from local action when on open-circuit. Following are the particulars of a homemade Edison battery which can be built very cheaply and which will give every satisfaction.
THE following article tells how anyone possessing ordinary working tools, can easily, quickly and inexpensively construct a mast of a distinctly modern type not usually found at amateur stations. Since it is built of wood, the mast is light and easy to erect.
E. C. M., Philadelphia, Pa., inquires: Q. I. Why are variable condensers of the rotary type used in preference to the sliding plate variable? A. I. Because they are usually better mechanically. Q. 2. Please give a formula for finding the capacity of a variable condenser and a condenser of fixed value.
THE steam-engine shown in the drawings is one requiring no machine work and is so designed that any ambitious amateur may feel certain of success if he is at all careful in his work. The base should be worked out to the size shown in Plate 2. If no iron base is at hand the hardwood base shown may be covered with either tin or sheet-brass.
MODERN methods of warfare have developed, among other things, the throwing of hand grenades, or bombs,—projectiles which are used at close quarters against an enemy’s trench and also for the purpose of resisting a rush. The use of this weapon does not depend so much on the amount of actual damage which it accomplishes as it does upon the disorganizing results in the ranks of the enemy following the explosion.
THE ordinary hammock is no good to sleep in. A special fitting called a spreader improves it, but not enough for real rest. To sleep in absolute comfort, the hammock must support the sleeper without sag. The hammock described does this. Make a frame of ⅞ in. by 2½ ins. hardwood bars.
A TOY Zeppelin is not a difficult or expensive thing to make in the home workshop. All that one needs at the outset is three or four toy balloons and some rattan strips. The first operation is to cut two conical pieces A A1 out of cork. These are ¾ in. in diameter at the base, and ⅜ in. at the apex, the body being ¾ in. long.
IT is hard to imagine art as a business builder for the farmer of Minnesota, or in fact of any other state. Most art programs shoot into space. They over-reach the mark, with the result that art, instead of becoming a common possession of the common people, is a pastime or pleasure and the plaything of the wealthy.
The battlefield is to the aeronautic engineer a huge laboratory for the testing of aeroplanes. More progress has been made in designing flying machines since the war began than most of us imagine. Wouldn’t you like to know just what the war has done to bring us measurably nearer the day when we will trundle out a flying machine as easily as if it were an automobile and whirr away from our country homes to our offices?