ON SATURDAY, April 18th, Bob Connery dropped in to see Steve Endicott at the latter’s office. Both men were rival automobile salesmen, and quite friendly. After comparing notes on the number of sales each had made during the past month, their talk gradually drifted into a discussion of the depression, as most conversations ultimately do these days.
NEXT to getting a refrigerator that is well made, the most important thing to consider is size. It is not only inconvenient to have an undersized refrigerator, but overloading a box raises the temperature and interferes with proper air circulation.
I AM a sign painter confronted with a big problem. The trouble is, that ninety-five percent of English words are misspelled. I mean the wrong letters are used such as C for K and Ph for F and the E at the end of the word when it should be somewhere in the middle or left out altogether, and double letters and silent letters.
A NEW type of detective is stepping from the pages of fiction to fight the modern criminal. He is hunting the big game of the underworld with strange new weapons; following a trail of hidden clues with delicate machines that almost think; using, as the tools of his trade, the thousand and one recent discoveries of science.
Is It Possible to Learn the Truth About the Habits of Alleged Man-Eaters in the Semitropic Water? Here Is the Report of a Study Made for Popular Science Monthly by One Who Now Fears the Swift Monsters
JOHN CHAPMAN HILDER
SOME years ago, I heard a celebrated naturalist state unequivocally that sharks would not attack men. As proof of his statement, he cited his own experience in shark-infested waters. Clad only in a bathing suit and a diving helmet, he had descended to the sea bottom, staying there for considerable periods while sharks and other fish swam negligently about, merely evincing a mild curiosity in his presence.
Others are covered with hair and all young infants can hang by their hands like monkeys in the trees
DR. W. K. GREGORY
WILLIAM K. GREGORY, internationally famous scientist of the American Museum of Natural History, in conversation with Michel Mok, staff writer, has explained that the earth, a mass of hot solar gas, was torn from the sun about two billion years ago by another passing star.
WORKING with a tiny needle and a wafer-thin piece of sheet metal, William A. Wallace, New York photographer, has taken an amazing series of pictures of New York skyscrapers. From street level to topmost floor, he has registered every detail on his film with his camera placed just across the street from these architectural giants.
DEATH all but overtook Private Harold L. Osborne, U. S. Army Air Corps, at Selfridge Field, Mich., the other day, when he attempted a 2,000-foot parachute leap. His opening ’chute caught the tail of the plane. For forty-five minutes Osborne dangled in mid-air behind the speeding craft.
ON THE Baltimore and Ohio Railroad the other day an unusual train was put into service. It is the first completely air-cooled passenger train ever used on a regular run. Manufactured weather is supplied to its passengers by devices that suck in air, wash it free of dust by water jets, and cool it by refrigeration before it is passed into the cars.
RESEMBLING a baseball catcher’s mask a new helmet protects British coast guardsmen from injury when scaling cliffs. At many points along the English coast, the only means of saving life in shipwreck is by climbing down the face of cliffs hundreds of feet high. The heavy wicker mask was devised to protect the guardsman duringsuch descent from abrasive injury by the rough surface of rocks and also from the attacks of birds that make their nests in crevices of the cliff.
AT THE touch of a handle like an air brake valve, an auto transmission, perfected recently by a Brazilian automobile engineer, works clutch and gear shift by compressed air furnished by a small pump on the engine. The “gears” of this transmission are always in mesh, and make but little noise while being changed.
WHEN J. M. Custer, a garage man of Piggott, Ark., set out to build his car, this three-wheeled vehicle was the result. All the material came from the junk pile, and the completed machine cost its builder sixty cents. Several of Custer’s own inventions are built into the car.
A HUGE yellow balloon soared skyward, a few weeks ago, from Augsberg, Germany. Instead of a basket, it trailed an air-tight black-and-silver aluminum ball. Within Prof. Auguste Piccard, physicist, and Charles Kipfer aimed to explore the air 50,000 feet up.
MANY believed that the ultimate limit in high-speed photography had been reached when Baron Shiba, Japanese engineer, announced not long ago a camera that could take 40,500 pictures a second (P.S.M., May '31, p. 143). Now, however, the Japanese Institute of Aeronautical Research at Tokyo has installed an amazing camera that can take as many as 60,000 photographs in a single second’s time.
A STRANGE contrivance that looks for bumps in roads and then marks them made its appearance on the highways of the state of Ohio the other day. It is propelled by a motor car, and whenever it passes over a bump in the road's surface, paint is automatically sprayed on the bump, marking it so repairmen can easily find it and smooth it off.
WHERE Army cavalry are not to be displaced by armored cars, as described on another page of this issue, because of rough terrain over which only horses can travel, this arm of the service is being brought up to date with ultra-modern instruments of warfare.
AT THE naval gunnery station near Portsmouth, England, the other day British tars staged an odd race to show what sailors could do ashore. Cables were rigged between platforms that represented opposite sides of a chasm in mountainous country.
A WESTERN inventor borrowed an idea from the trench periscopes of World War days and evolved the instrument shown below for the sport fan. No matter how difficult it is to get to the front rank of spectators, the user always has a clear view.
JUST what a mad dog's bark sounds like was brought home vividly to Los Angeles, Calif., radio listeners recently. The voice of a caged dog suffering from hydrophobia was recorded on a phonograph record. Then it was broadcast, together with the bark of a normal animal, to warn the public when to keep away from a suspiciously acting dog.
TERMITES, antlike insects that attack wooden houses, commit their depredations unseen. Unless the owner detects their hidden mud tunnels, he has no warning until their work is finished. Now a southern California man has patented a sound amplifying device intended to reveal them at work.
Chicago Police, Trained to Handle Armed Men, Show, in Series of Pictures, How Weapons Can Be Wrested from Footpad
WHAT TO DO AND HOW. Photos on this and following page give a good idea of how officers are taught to disarm a thug even after he has them covered. Above, Sergeant John Leonard, right, and Detective William Foley, of the Chicago Police Department, pose for the first of the pictures in the series that proves that an armed man has not an unbeatable advantage even though he has his weapon in his hand and is desperate enough to use it.
IN NEW YORK CITY is a man whose job has no counterpart in the country. He is David C. Coyle, consulting engineer, and his self-appointed task is watching skyscrapers sway and shiver in the wind. Strange things happen when a stiff breeze hits a structure of forty stories or more.
CHICAGO is to have the largest post office in the world. The fifty-acre, twelve-story building will be completed and ready for occupancy within about a year and a half, according to a recent announcement of the United States Post Office Department.
Daring Men in Seven Nations Aim to Harness GIANT OCKETS
This article tells you the sensational facts the author learned while making a personal tour of the world’s rocket fields where elaborate tests are now under way.
G. EDWARD PENDRAY
FIFTEEN years ago the rocket was a toy, fit only for fireworks or laboratory demonstrations. Twelve years ago only one scientist in the world, the American physicist, Dr. Robert H. Goddard, of Clark University, Worcester, Mass., was working to transform this ancient plaything into a source of power for fast vehicles.
A veteran pilot's thrilling story of hazards met in big planes over America's toughest flying country
HARRY W. HUKING
TEN thousand feet in the air. Around me the blackness of a cloudy, moonless night. In my ears the roar of three powerful motors. In the cabin back of me, passengers and mail for whose safety I, and I alone, am responsible. Before us is the great Hump of the Rocky Mountains, rising to more than 9.000 feet.
SECRET trapdoors that swing ponderously upward at a button's touch, and apparently solid walls of brick that open on hidden hinges—such scenes as these, hitherto found only in movie thrillers, greeted the eyes of prohibition agents the other day when they raided a veritable bootleggers’ castle in the heart of New York City.
IN MAKING tests to find how hearing “works,” research workers at Princeton University, Princeton, N. J., have found that bullfrogs and turtles are deaf to human speech. The only sounds that are audible to these creatures are those that resembled the croak of the bullfrog.
RECENTLY invented, a new kind of ultra-violet lamp for home and office contains the health-giving rays and is also suitable for general illumination. Its light is white with a slightly bluish tinge. The light comes from a small spiral of glass tubing, which contains mercury vapor and a secret mixture of rare gases.
EVERY schoolboy knows that sound carries best over water. But it remained for Christian A. Volf, Jr., New York acoustical engineer, to build this idea into a loudspeaker and a method of recording sound for talking pictures. Recently Volf exhibited two models of a new loudspeaker with a trough of water built into the base to project into the air sounds directed against it by a series of pipes.
SCHOOLBOYS of Wilmette, Ill., search the heavens, following the stars in their course, through an astronomical telescope in a public school observatory. This, believed to be the only grammar school observatory in the United States, was paid for by money that school pupils contributed over a period of six years.
THE “culti-mulcher,” a new farm implement, does four jobs at once, thereby saving time for the farmer. The machine was demonstrated at the Federal experimental farm at Arlington, Va., a short while ago, and received much favorable comment from officials.
AN ELECTRIC motor drives a new pencil sharpener that makes quick work of its job. A pencil is held in an opening at one end of a transparent casing like those seen on hand-operated sharpeners. Then a little switch on top of the motor is thrown and the little machine, humming softly, sharpens the pencil neatly and quickly.
LARGEST of locomotive tenders are two now being tried out with fast passenger engines of the Pennsylvania Railroad. Each can carry twenty-five tons of coal and 25,000 gallons of water. The capacity of their tanks is thus greater than that of many swimming pools.
NEW apparatus, of almost human intelligence, aids in transmitting the Western Union Telegraph Company’s time service to subscribers in all parts of the country. Improved synchronizing and testing machines have recently been installed in the telegraph company’s new building in New York City.
Terms Used by Weather Man May Confuse You but This Article Tells Their Exact Meaning
W. J. HUMPHREYS
FLYING into a thick haze one morning, an airplane pilot was astonished to notice that he could see better with his new amber goggles than without them. A few days later, flying through a similar haze, he was amazed to find that his goggles actually obscured his vision.
PICTURES on these pages tell more vividly than words of the impending passing of the United States Army's most romantic arm— the mounted cavalry. Horses are too slow for modern warfare, says the Army’s Chief of Staff. Except for maneuvers in some cases of especially difficult terrain,” they will be replaced by fast tanks, as shown on the opposite page.
NEW YORK posed for its flashlight picture recently. Army flyers, soaring over the city late at night, demonstrated one of the newest wrinkles in aerial photography by dropping a huge flashlight bomb of three billion candlepower from the air.
ROARING through the air in a plane at a speed of one hundred miles an hour, plant disease specialists of the United States Department of Agriculture literally comb the ether for spores of black stem rust, a disease that causes an annual loss of many millions to wheat farmers.
UNCLE SAM’S big aircraft carriers Lexington and Saratoga recently had distinguishing marks painted on their funnels so pilots can identify them from the air. The Lexington funnel was given a broad black horizontal band while the Saratoga was given a vertical black stripe.
ACCIDENTS are made to order in airplane manufacturing plants so that pilots and passengers may safely trust their lives to new models of planes. At the plant of a Burbank, Calif., aircraft builder, landing gears for new designs are given a heavy load of sandbags and then dropped from heights of several feet.
LAUNCHING a nineton bombing plane with a catapult seems almost as incongruous as firing a twelveinch shell from a peashooter. Yet that is the extraordinary feat accomplished by the mightiest of all catapults, recently demonstrated at Farnborough, England.
TINY colored lights on a big wall map at the Naval Air Station, Anacostia, D. C., show aviators what the weather is like over the entire central eastern part of the United States. White lights indicate good flying weather; green lights, poor flying conditions; and red lights show them that the weather is bad.
THE first glider fitted with windmill vanes, made familiar by autogiros, appeared at a German airport the other day. On a vertical post before the pilot’s cockpit the vanes, like a big fourbladed propeller laid horizontal, were mounted.
MECHANIZING armies has so greatly speeded up land warfare that field artillerymen now have to learn to shoot, as do naval gunners, at rapidly-moving targets, with their fire controlled by observers in airplanes high overhead. Preparing for the day when they may be pitted against fast-moving tanks and armored cars.
A NEW hack saw frame is designed for making shallow cuts such as in cutting the metal sheathing on BX cable or working in close quarters. Instead of the familiar deep “D”-shaped frame of standard saws, this one has a shallow frame that fits closely along the blade’s top.
WOULD you go more than one and a half times around the world for a pound of honey? According to bee experts, a bee travels about that distance in making a pound of honey. Bees that were watched made about 10,000 round trips of two miles each to gather enough nectar to make half a pound of honey.
FAMILIAR to many are the fake houses used on movie lots, where only the front is needed for a scene. A clever Pennsylvania real estate man adopted the same idea recently. Approaching motorists see what, apparently, is a full-sized, attractive Colonial dwelling.
LAST month George Waltz related how he first became interested in television when he heard the peculiar buzz-saw signals of vision transmission on a short wave receiver. Later he visited one of New York City’s sight broadcasting stations and was so fascinated by what he saw that he decided to build a television receiver.
Century-Old Man is Only Survivor of Stone Age Race
F. W. FITZSIMONS
NOT long ago I discovered a century-old native, believed to be the last of the Cape Bushmen who inhabited South Africa as far back as the Stone Age. My Cape Bushman is 107 years old, blind, deaf, and barely able to stand. He can, however, still enjoy a pipeful of tobacco.
HOW NEON LIGHTS ARE MADE. The story of the strange new light, invented by Georges Claude, French engineer, told in photos. FIRST STEP IN MAKING A NEON SIGN. An artist draws a design which includes lettering and decoration, and this design is then enlarged to desired size so tubes can be right dimensions.
TWO expeditions, one German, one British, established outposts upon the forbidding ice cap of central Greenland, last year, seeking a possible landing place for transatlantic airplanes. Searchers with airplane and dog teams found Augustine Courtauld of the British Arctic Air Route Expedition, this spring, hungry and unshaven.
THE Mystery of Meteor Crater is apparently solved. This gigantic pit in the desert near Winslow, Ariz., big enough, if flooded, to float the whole American Navy, has been for years the subject of controversy among scientists. One camp held that an underground steam explosion caused it; the other, that it was hewed out by an enormous meteor.
AN ARGENTINE inventor has patented a device to warn sleepers of an earthquake in time for them to dress and leave the house. At the first trembling of the earth, this invention automatically turns on all the lights in the house and rings a bell.
HOT dogs from a coin-in-the-slot machine were a recent innovation at a German fair. After depositing the right coin, customers turned a crank and out came hot dog, bread, and mustard on a paper plate. The frankfurters are steamheated until the crank is turned.
DUMMY tanks made of wood played the part of actual vehicles in recent German army maneuvers. Shown in the photograph at the right, reproduced by courtesy of La Science et la Vie, they enabled attack groups to act realistically in practice.
CLOSING at night and opening to the sun are strange characteristics of flowers. Stranger still is the fact that each kind of flower has its own favorite opening hour. Some expand to the first rays of the rising sun, but others refuse to open an eye until long past noon.
Nature, Carving Vast Caves in Rock, Surpasses Man's Mightiest Efforts
The Remarkable Photographs on These Two Pages Are from the Album of Carl B. Livingston, of New Mexico, Who Has Spent a Lifetime Exploring Underground Caverns and Studying the Processes by Which They Are Formed During the Course of Centuries
HEKNOWSCAVES. Below, Carl B. Livingston, who tells here the picture story of caves, emerges from a newly found shaft. SEEING THE WORLD. At left, view of the Guadalupe Mountains as seen from the entrance to one of the region’s big caves. NATURE’S WATER PIPES.
WITH motors wide open and propellers churning the water into swirling foam, three speedy motorboats raced side by side without advancing a foot. The event was a unique “standing still” motorboat race, held in a small swimming pool during a motorboat show in California.
SO RAPID is the growth of a mushroom-like fungus found in Hawaii that the human eye can easily see it increase in size. Probably the fastest-growing plant in the world, its stalk reaches a height of several inches in one minute’s time.
A NEW kind of windmill, far more efficient than the many-bladed affairs of the past, may once again cause men to harness the winds for power. A noted Finnish engineer, S. J. Savonius, recently told the American Society of Mechanical Engineers that this might happen.
UNUSUAL in its shape is a huge incandescent bulb recently built in Germany. Intended for such uses as movie studio lighting and aviation beacons, it requires 50,000 watts of electricity to keep its filament glowing. This is sufficient electric power to feed a hundred ordinary flatirons, or to run an electric motor of more than sixty horsepower.
VIOLENTLY roaring and chattering, a new Dutch ditch digger goes to work along the shores of the Zuider Zee. This machine works much like the rotary snowplows used on some American railways, for it bores its way through the earth as they do through snowdrifts.
A RADIO set demonstrated recently by Alexis Poncel, of Brooklyn, N. Y., its builder, can be plugged into either a direct or alternating current circuit for operation. A relay in the power circuit is so arranged that it does not function when the set is running on alternating current.
A NEW knob for the gear shift lever is a handy receptacle for carrying coins, tickets, and other articles. The cap is removable, exposing a small compartment in the hollow knob. The lid screws on firmly and there is room in the cavity for several small articles.
A NOVEL toy cannon gets its crash in the same manner as you make a noise by striking and bursting an inflated paper bag. At the rear of the cannon is a rubber ball partly open at its bottom. Across this opening a thin strip of paper is unrolled from a coil.
GOLFERS are now offered a score card made of aerial photographs. An aviator makes an air map of the course, from which individual pictures of each hole are taken. These are bound together in book form. On each picture distances along the fairway are marked in hundreds of yards.
IN PATRICK County, Va., and nowhere else in the world, is found the “fairy cross” of the Virginia Blue Ridge, a rock formation taking the form of a perfect cross, and for which science has found no satisfactory explanation. Each of these little brown rocks, worn smooth by no one knows how many centuries of exposure to the elements, bears the form of a cross, often as clearly outlined as though chiseled by the hand of a master.
IN WASHINGTON, D. C., the younger members of the Y. M. C. A. have formed a novel camera club. Each member builds his own camera out of cardboard, with a pinhole in a piece of black paper for a lens and cardboard for a shutter. Standard three and one fourth by four and one fourth inch cut films are used.
UNBREAKABLE spectacle lenses are a recent invention. Two pieces of glass with a piece of celluloid between them are cemented together under pressure, forming one solid piece. This “glass sandwich” is slightly thicker than ordinary glass but it is just as transparent, the celluloid being invisible.
THROUGHOUT British Africa, hunting lions from airplanes has been prohibited. The open nature of African game country has made use of planes for this sport comparatively easy. Authorities now fear that continuance of the practice may result in extermination of the “king of beasts.”
FREIGHT transported on wheels directly from manufacturer to consumer, without a single stop for unloading and reloading en route, is the proposal of Col. Joseph C. Bonner, transportation engineer. Recently he demonstrated in New York City, with the aid of models, how “rail wagons” of his invention would make this possible for steam railroads.
A NEW electric cord for portable appliances like vacuum cleaners, flat irons, or drills cannot kink or snarl. It is encircled by a wire guiding device. This consists of alternately straight and looped wire, extending outside the electric cord for its entire length. The wire thus keeps the cord free of kinks for the distance from plug to appliance, without shortening its scope. While the new cord is nonkinking, it remains perfectly flexible and may be bent around or over obstructions like any standard cord.
Now bird cages are acquiring all the comforts of home. A new bird bath compartment for cages is made of glass, like those in the latest bathrooms. Canaries may splash around to their hearts’ content, without scattering water over their surroundings.
THE “little red schoolhouse” of the future, according to Joseph Duke Harrison, New York City architect, may resemble a wedding cake on a platter. Recently he exhibited a design for a large circular structure with walls and most of its roof of glass.
AN EARLY start upon an inventive career is that of Warren Prince, high school senior of Kansas City, Mo., who already has two patents to his credit. Recently he demonstrated one of his inventions—a mechanical whistler that will transform the most casual purser of lips into an accomplished musician.
A PLOW that works while the farmer sleeps was tried out the other day at Northampton, England. Set in motion one evening it obediently worked all night long without human attention, plowing a broad field in the course of its night’s work. This odd machine is driven by a gasoline engine that works two cable drums.
A FLEXIBLE conveyor system on wheels for loading and unloading freight cars carrying bagged and baled materials has just been placed on the market. It speeds up the work, requires fewer men, and can be moved about to send the bags around corners or into the warehouse rooms.
NO TIMEPIECE on earth, however accurate, can give the true solar time of noon except on December 25, April 16, June 15, and September 2. On every other day of the year every clock or watch is either behind or ahead of the true solar noon told by a sundial.
IN A little workshop in Los Angeles, Calif., sits a man who for your amusement distorts normal looking movie actors and actresses into freaks. He is James Herron, and he makes the lenses by which strange distorted effects are produced in some motion picture comedies.
LIKE the horn of a gigantic megaphone, the barrel of a new refracting telescope at Berlin-Treptow, Germany, looms up over its surroundings. This huge instrument, almost as long as an American railway passenger car, is said to be the largest of its kind in the world.
SHAPED like a segment of melon rind and suspended by its points from the arms of a semicircular frame is a new sundial invented by a California man. It tells time with equal accuracy in summer or winter. Red lines for the hours and fractions, and black lines for the minutes, cross the inner surface of the bronze casting.
A NEW oil burner for home use is portable and as easily installed as a vacuum cleaner. It requires no permanent system of pipes or wiring, no changes in furnace bricking, or the removal of grates. When being installed its nozzle is thrust into the opened furnace door, an electric cord is plugged into a lighting socket, and the burner is ready for full automatic operation.
UNKNOWN to most American tables are screw beans, one of the strange foods that hundred of years ago helped stay the hunger of Indians. But one of these days they may appear at the corner vegetable market, if the plans of the U. S. Department of Agriculture materialize.
A RADIO set that can be carried about like a suit case is designed for the convenience of fans who do not want to miss favorite programs while motoring. Fitted with two connector cables, it can be plugged into a lighting socket in the home or to a socket wired to the batteries of a motor car.
ONE of the newest of exercising devices is a mechanism that somewhat resembles a hobbyhorse without rockers. Seated in its saddle and operating this odd contrivance, the user can exercise and develop all the principle muscles of his body.
A BRUTAL load was imposed on the streets of Oakland, Calif., the other day when a 105-ton girder, said to be the largest ever put together on the Pacific coast, was moved over them, to be used to support the balcony of an Oakland theater. The drawing and photograph above show the unusual method used for this task.
RADIO music, instead of code signals from special stations, soon may be a means of guiding ships into port. A new radio direction finder, demonstrated the other day by its inventor, Gerhard Fisher, of Los Angeles, Calif., can be employed to pick up radio programs from broadcasting stations.
A NEW type of motorcycle is a convenience to garage men who have to deliver cars at the homes of customers. When an attendant goes out with such a machine, he tows one of the new motorcycles behind it. Having delivered the auto, he mounts his motorcycle and drives back to the garage.
BEGINNERS at golf can now use a driver with a spirit level set prominently in its head. When addressing the ball, one can see at a glance whether or not the sole of the club is being held flat on the ground. Practice with this driver is said to aid in acquiring a proper swing and in following the true arc of a circle.
HAS Junior a natural ear for music? Or are his piano lessons wasted effort? It’s easy to find out at once, according to Prof. Harold M. Williams, of the University of Iowa Child Welfare Research Station. Tests he has devised show whether a child has a real sense of rhythm and whether he can keep a tune in singing.
A SCARECROW that talks keeps fruit-eating birds away from a berry farm near Portland, Ore. When the farmer discovered that his berry patches were furnishing free meals for large flocks of crows and robins, he rigged a loudspeaker up inside his scarecrow.
DUST made by a new portable sandpapering machine is caught by a bag on the machine itself in much the same manner as sweepings are collected in the sack of a vacuum cleaner. A powerful fan creates a vacuum, drawing dust off the sanding belt and depositing it in the bag.
AN ODD shovel that is expected to lighten the labors of its user and speed up his work has two handles. It resembles a standard shovel with an ordinary handle, except that a second grip has been pivoted to the longer one just back of the shovel blade. When in use the workman takes hold of the shorter handle with his left hand. This gives a good leverage and enables him to dig and maintain a comparatively upright position, less tiring than backbreaking crouching posture formerly necessary.
YOUR doorbell becomes a fire alarm with the addition of one or more new fire-detecting buttons connected in the circuit and placed at points of vantage. Whenever the temperature rises beyond a predetermined point, an electric contact is made automatically on the button. The doorbell then rings the alarm. If preferred, the button may be wired to the telephone; in case of fire it would close the circuit just as if the receiver were lifted, indicating trouble to the operator.
A MAN and his dog share the use of a “pet chair,” a recent innovation in furniture for the homes of animal lovers. The top of this chair and its seat resemble any other. But the chair’s bottom is a compartment that provides a home for the household pet, and shields it from drafts. There are several styles of “pet chairs” to harmonize with any collection of furniture. Another novelty is a small settee, with a hollow interior for a cat.
FROM an airplane, an odd prison in Copenhagen, Denmark, bears a striking resemblance to a group of large wagon wheels lying on the ground. A number of circular structures built around the main prison buildings have walls extending from their rims to central points like spokes in wagon wheels.
AN AUTOMOBILE tire that inhales and exhales air through rows of pores in its outer tread is a new invention. This aircooling is said to remove the internal heat generated by high-speed driving, lessening the chance of a blow-out and making possible a thicker and longer-wearing tread.
A NEW device hung on a car’s right door settles the oftendisputed question of how many miles its owner gets from a gallon of gasoline. This portable instrument board contains a small glass bulb holding exactly one tenth of a gallon, a three-way cock, and a small electric pump.
RECENT landslides in France, one of which killed a General of the U. S. Marines, lend interest to a hitherto untold story of quick-witted action. When a landslide spread death among the inhabitants of Lyon, France, a few months ago, radio amateurs of that city rigged up an apparatus within a few hours to give advance warning of further earth slips.
CONSIDER the people you know and you will find, almost without exception, that the ones who take the keenest interest in living, who are least subject to mental depression, and who get the most out of life are those who take an intense interest in some hobby.
Interference between Stages That Causes Squeals Stopped by Solid Wall of Metal— Disconnecting Speaker Wires All at Once
RULES FOR SHIELDING
THERE are many occasions when the amateur radio experimenter needs a method of disconnecting a number of wires at one time. The modern dynamic loudspeaker requires four connections, two for the field supply and two for the voice coil or to the primary of the voice coil transformer.
A RADIO receiver as built today consists of a chassis, a loudspeaker, and a cabinet. The chassis will, of course, function just as well without the cabinet, but that is not true of the loudspeaker. The cabinet really is part of the loudspeaker.
YOUR modern screen grid broadcast receiver can be easily converted into a short wave unit that will give you satisfaction if you follow the few simple directions for an original circuit which are given in this unusual radio article.
THIS superheterodyne short wave converter unit has several features that will appeal to the amateur radio experimenter. To begin with, it is cheaper to build, I think, than any similar circuit so far developed. The unit makes use of three radio tubes, one type 227 and two type 224 screen grid A. C. tubes.
Modern Motors Throw Strain on Spark Plugs and High Tension Wires So Good Cables Are Needed—Setting Timer Simple in Eight-Cylinder Car
ONE sizzling hot summer evening, while Gus Wilson and Joe Clark were working late on a rush job, a year-old eight-cylinder sedan drew up in front of the Model Garage and the owner climbed out. “Howdy, gentlemen,” he drawled as he strolled over to the garagemen. “I see you-all are still making hay though the sun is down.
THIS strange sea horse provides the thrills of broncho-busting — with a ducking to penalize every slip! It’s a nautical nag upon which as many as five small water riders may get astride at one time, yet it is made of nothing more than an old board and a pair of large, empty cans.
THIS single-stick airplane model of ten simple parts is so designed that it can be converted into twenty different types of flying models. It opens new fields for the model enthusiast to conquer. Through building it, the beginner can master a variety of construction methods while actually expending the time and material necessary to make only one model; and the expert can adapt the principles for use on any pet model of his own.
A New Fad for Ship Modelers— Carving Tiny Ocean Liners
DONALD W. CLARK
HERE is a brand-new idea for the model maker who enjoys whittling—a model of one of the world’s fastest steamships, the Bremen. Little wonder, when you consider their novelty and simplicity of construction, that very small models of ocean-going vessels are fast becoming popular.
A simple and quickly applied rule for choosing the correct shutter speed and adjusting the opening in the diaphragm
Follow These Five Rules to Get Good Pictures
F. D. RYDER
WHEN I first started to take photographs, a long while ago, I had a small box camera. The instruction book said to take snapshots only in sunlight between the hours of nine in the morning and three in the afternoon, so I took pictures only on sunny days.
Colorful Shellacked Cloth Tops Add Novel Note to Tables
COLORFUL chintz and other decoratively figured fabrics make attractive and serviceable coverings for table tops. They are suitable for kitchen tables, dressers, card tables, children’s furniture, and the like. There are several ways in which you can apply and treat the cloth.
EVERY mother will welcome a toy box fashioned in a shape so attractive to children that they will cheerfully gather up their toys. Such a box is the miniature circus cage illustrated. The brilliantly colored wagon is mounted on casters so that it can be pulled from place to place by a small child even when fully loaded.
We complete the hull and rigging for our Combination Sailboat-Motorboat
NO MATTER what preferences you may have regarding a small boat, Dauntless will meet your requirements far more completely than any ordinary design. Pleasure jaunts, quick trips to town, fishing, hunting, sailing, motorboating—all these come within the scope of this 15-ft. combination boat built to operate efficiently with either sail or outboard motor.
HOME owners often have to plane the edges of a door or sash that binds or make other repairs to them, and it is usually a problem to find a suitable way to hold them while the work is being done. Carpenters have many makeshifts for this purpose, but a nonslipping clamp made as shown is much better because it holds work of various thicknesses with a powerful grip.
WHEN the lacquer on silver, brass, and copper articles becomes checked and chips off, as often happens, the pieces quickly show discoloration in places and require to be repolished. Before this can be done, however, it is necessary to remove the lacquer.
DESIGNED especially to please children, this unusual seat with dog-shaped ends makes an attractive addition to any garden nook. Each of the dogs is 24 in. high to the tip of the ear and 22 in. wide over all. They are sawed from a wide board of 1 in. thick pine, cypress, or other durable wood.
THE object of this novel new game is to flip the “egg” upside down and catch it as nearly as possible in the center of the “frying pan.” Any player who succeeds in catching it within the inner circle wins first place; the other players are credited with the number of the outer or largest circle within which the “egg” falls.
ANYONE who uses the drawing board frequently, especially for machine designing, will find it convenient to fasten all the necessary data sheets to the T-square and cover them with a strip of clear celluloid. Decimal equivalents, screw threads, sheet metal and wire gages, drill and tap sizes, and other information may be kept available in this way.
FOR sharpening small circular saws, the only equipment needed is a circular saw filing vise, a hand saw set, an 8-in. double-cut smooth flat file, an 8-in. round file, and 8-, 10-, and 12-in. regular taper saw files, all with handles. The saw files are of the heaviest triangular type used for handsaws, and they have single-cut, smooth teeth.
How to prepare gorgeous false faces for use as decorations or in theatricals and entertainments
KENNETH M. SWEZEY
BEFORE men made idols, they made masks. It gave them a great sense of primitive power—the power to create new faces that could transform a man in a twinkling to god, beast, or devil. As if by magic, they could emphasize a hundredfold any human mood and bring to real existence the strange and colored caprices of their imagination.
Runway for Working Under Car—Foiling the Tire Thief
MANY jobs on the front or rear running gear of an automobile are awkward because there is so little room to work. A pit solves the problem but is not practical for many owners. A good solution is shown in Fig. 1. Short, strong runways are constructed from sections of two by four and two by six inch lumber.
FIG. 3, above, shows an excellent way to protect the spare tire from theft. It operates electrically so that if anyone attempts to remove the tire the horn will start to blow and keep it up till shut off by the owner. The exact details of installations will, of course, depend on the type of car and the method of carrying the spare tire.
IT IS often extremely difficult to remove a bushing from a “blind” hole. A method often recommended is to run a tap into the bushing which will cut threads so that a bolt can be screwed in. Force can be applied to the projecting head of the bolt and so pull out the bushing.
A DOOR not properly latched may swing a serious accident, especchildren in the car. And rear seats are unoccupied, door may collide with a post the garage and be torn off ted. the left, shows a way to or indicator that will show at hether all the doors are locked he idea is to install in each door uch as is fitted to the house door lar alarm system.
IN THE small machine shop which has only a small volume of production, forming tools must be made quickly, easily, and—above all else—inexpensively. In the larger plants these tools are made from a master former, but in shops of smaller size a more economical method must be used in order to keep down the cost.
RECENTLY, the writer was called upon to machine a number of valve stems for ice machines from ¾-in. cold-rolled stock. This work was done on the turret lathe; and as the stems were long and the stock did not run very true, considerable difficulty was experienced in maintaining accuracy until we hit upon the following method:
MANY letters suggesting ideas for decorative, story-telling novelties that can be made at home were submitted in the contest announced in connection with Charles H. Alder's article, “Treasure Island Smoker’s Tray” (P. S. M., Apr. ’31, p. 87).
EDWARD THATCHER tells how to convert glass jars into Decorative Lighting Fixtures
Are You Using Out Blueprints?
ATTRACTIVE electric lanterns or wall bracket fixtures can be made with very little work and trifling expense from many types of discarded glass containers in which foodstuffs have been packed. The containers are not cut or altered in any way, but vents are provided in the housing at the top to allow the heat to escape.
IN WORKING thin sheet aluminum, it is often a tedious job to file it to shape because the teeth of the file tend to become clogged and the softness of the material makes it difficult to obtain a true edge. The very fact, however, that aluminum is no harder than some woods allows it to be trimmed successfully with an ordinary block plane.
REALISTIC exhaust pipes for scale model airplanes which have in-line and V-type engines can be made easily from aluminum tubing. My own practice is to use an 8-in. length of 3/16 in. diameter tubing and cut from it two pieces 2¼ in. long.
A SIMPLE way to label tin cans or other metal containers used for the storage of nails, screws, and other hardware is to cut two or four slits in the container and insert one of the nails or screws in the manner illustrated. If desired, a strip behind the nail or screw may be painted white as a background.
MY BASEMENT workshop is brilliantly lighted by several 150-watt lamps. On several occasions I have forgotten to switch them off, and even a few such nights result in an appreciable addition to my monthly electric bill. As a reminder to prevent further forgetfulness, I attached a bell-ringing transformer (costing only a dollar) to the lighting circuit in the basement, and ran a pair of bell-wire leads upstairs to a miniature lamp socket mounted on the wall near the exit from the cellar stairs.
A RCHERY grows in popularity season by season. Many new clubs have been formed, and archers now have every opportunity to indulge in target shooting, archery golf, roving—competitive shooting from one mark to another —and even hunting.
WHILE building a clipper ship model 18 in. long over all, I came to the conclusion that deadeyes small enough for the model would be too costly and would take too much time to rig, so I hit upon an inexpensive substitute—wire eyes of the type sold for use with hooks on women’s dresses.
NUTRITIVE pills which have a miraculously stimulating effect upon plant growth have been developed experimentally in recent years (P. S. M., Oct. ’29, p. 29, July ’30, p. 26, and Jan. ’31, p. 56), but they have not yet reached the market in a commercial form.
FUNNY faces cut from newspaper comic strips form the moving targets of this novel and amusing toy shooting gallery. The faces are pasted on cardboard disks which are mounted on an endless fabric belt turned by means of a crank. The shooting is done with a simply made wooden pistol 6 in. long which uses rubber bands for ammunition.
How to Construct Woodsy Fittings That Add Charm to a Log Cabin
WILLIAM G. DORR
IN ANY well-designed and carefully constructed log cabin such as that described last month (P. S. M., July '31, p. 92) and shown in POPULAR SCIENCE MONTHLY Blueprint No. 134 (see page 91), there are certain features that add materially to the charm of its appearance.
WALL PAPERING TABLE SET UP ON FOLDING IRONING BOARD
THOSE who undertake wall papering at home rarely can find a suitable place to spread the paper and apply the paste. Neither the kitchen table nor the hall floor is a satisfactory substitute for a paper hanger’s bench. What does serve the purpose very well, however, is a common folding ironing board upon which is laid a top of any convenient length made by fastening two 1 by 10 in. boards together with battens underneath.
PHOTOGRAPHS can be copied without difficulty even with a small and inexpensive camera if a simple homemade enlarging outfit is available similar to that recently described in an article by Everett Eames (P.S.M., Mar. ’31, p. 96). One of these enlarging machines was constructed by Ronald G. Sechler, of Norristown, Pa., who found that it worked even better than he had hoped.
Tired of building ordinary furniture? Then consider this distinctive desk, which is in the latest mode yet not too extreme. The piece was designed and built by W. E. Mitchell, who is president of an automobile financing company in Spokane, Wash. His hobby is cabinetmaking.
THE desk illustrated is of presentday or what is now often spoken of as “contemporary” design, but the general lines are not strictly modernistic and there is nothing harsh or clashing about them. Indeed, straight lines, if designed in harmony and simplicity, are as restful and beautiful as curves.
BOX OF HOT SAND KEEPS CHROMIUM PLATING SOLUTION WARM
THE problem of maintaining the correct temperature in chromium plating baths is easily solved by the convenient arrangement illustrated. Operating on the principle of the fireless cooker, this device eliminates the necessity of working in a hot room and removes the chances of obtaining a worthless, milky deposit because of the chilling of the solution.
TRELLISES improve the appearance of any home, but if they are attached directly to a house it requires a great deal of work to take down the vines when the building has to be repainted. By setting up trellises as shown in the accompanying drawings, this difficulty may be avoided.
HAVE you ever wished for a trestle or sawhorse that was adjustable as to length? Well, here it is, and it can be constructed from a set of slides taken from a discarded extension top dining table, four oak barrel staves, and two short sections of ¾-in. dowel rod.
IF YOU are looking for something unusual in furniture, the corner chair illustrated in Fig. 1 should prove to be an interesting project. Its characteristic features are the square seat, which sometimes has a rounded front corner; its cabriole leg, typical of the Queen Anne and Chippendale periods; and its three turned rear legs.
WHAT boy wouldn’t keep his ties in order if he had a comical clown tie rack like that illustrated? The outstretched arms and legs are hinged to the body so that they can be swung forward to make it easier to remove or replace the ties, yet the whole takes up little space on the wall.
SINCE oxy-acetylene cutting and welding torches have come into everyday use in shop and factory, it is no longer entirely safe or satisfactory to have sawbucks or sawhorses made of wood. The substitution of steel for wood is advantageous in every way.
THE volume of a harmonica can be increased for playing in public, especially in large auditoriums or outdoors, by amplifying the sound with a mediumsized megaphone. A slot is cut in the megaphone about 3 in. from the mouthpiece, and over this is riveted a metal holder made as illustrated below with two lips to grip the harmonica, which is of the “marine band” type.
THERE are a number of ways to cover the deck of an outboard racing boat such as the one shown on POPULAR SCIENCE MONTHLY Blueprints Nos. 128 and 129 (see page 91). One of the most original was developed by John G. McKean, of Alexandria, La., after he had visited an automobile show and seen a cutaway section of a popular make of car, the top of which had been stretched over fine gage poultry wire.
ON A LARGE California chicken ranch, several hundred water pans are kept filled by means of the simple and inexpensive type of automatic valve illustrated. An old automobile tire valve provides the principal part of the mechanism. It is fastened as shown to part of a discarded spark plug by means of molten lead.