"OH MARTHA," shouted Peter Ransom as he crossed the threshold, home from another day's work, "where are you?" "In the kitchen, dear," his wife called out. Peter dropped his coat on the hall table, cocked an expectant ear for some greeting from his daughter, got none and proceeded into the kitchen for further investigation.
Germs, some of which are dangerous, multiply fast in temperature above 50. So test your refrigerator.
F. G. PRYOR
HOW ways to has keep been food from a big spoiling problem. alDrying, smoking, or pickling was the way it was solved in early days, but the trouble was these methods changed the taste and characteristics of the food. Finally, it was found that by removing heat, food could be kept for a long time without losing any of its natural qualities.
You sort of poked fun at some of the primitive peoples who still do things just as their ancestors did. What about us? Are we really any better in that respect? What’s more primitive than a ferry, and yet it’s still widely used for no earthly reason, as far as I can see, except it was the best our ancestors could devise and so it’s good enough for us.
Remarkable demonstration in theater shows big improvement in seeing and hearing by radio. New process used to aid planes blinded by fog.
ROBERT E. MARTIN
TWO remarkable developments recently revived public interest in television, and brought the dream of practical transmission and reception of “images on the air” a step nearer realization. In a dramatic demonstration at Schenectady, N. Y., a few weeks ago, Dr. E. F. W. Alexanderson, consulting engineer of the General Electric Company, projected six-foot images bright enough to be seen by a large gathering.
Famous Flyer Tells How It Feels to Pilot Metal Giants of the Air
IT IS queer about big planes. They look like elephants and they fly like swallows. It is only when you take off and land that you realize how large they really are. A few years ago, I thought the wings of my seventy-fourfoot-span Ford were a mile long when I sat down after dark in a tree-lined cotton patch on a forced landing.
BUBBLES of brownish froth recently won a desperate battle against one of the biggest oil fires of history. When flames threatened to wipe out a great Bayonne, N. J., refinery, fire fighters, armed with the latest chemical equipment. saved the day.
Carrier Pigeons Bred by the Army at Fort Monmouth Fly in Darkness, Proving Old Fanciers Were Wrong
JOHN E. LODGE
NIGHT flying homing pigeons, something brandnew in the bird world, have been developed by experts of the United States Army Signal Corps at Fort Monmouth, N. J., where most of the carrier pigeons for the Army are bred and trained. In rearing and teaching these birds, the Government pigeoneers have accomplished a feat which for centuries was considered impossible.
CHICAGO is going to get natural gas. San Francisco already has it. New York may get it. This is likely to make radical changes in the daily lives of millions of Americans who live in, or near, those cities. For natural gas is cheap gas. Natural gas comes from wells where Nature put it and is free for the finding.
A DARING attempt to drive an automobile with the terrific power of fuels like benzine burning in liquid oxygen succeeded at Berlin the other day. Shortly after, one of its two inventors was killed when he sought to repeat the feat. Dr. Paul Heylandt, German liquid air expert, and Max Valier, builder of rocket cars, were in search of something more than merely a new kind of automobile.
FLOORS of steel for private dwellings may become a commonplace, one of these days. They will introduce to Americans the idea of building entire houses of steel, Lee H. Miller, New York engineer, recently told the American Iron and Steel Institute.
A NONMELTING, durable, artificial ice that should be a benefactor of hockey players and fancy skaters has been brought to the United States from Germany. Called “opal ice,” it is a secret composition made by adding hot water to certain chemicals.
IF YOU want to keep house flies out of a room, try fitting the windows with yellow or red panes of glass. That is the conclusion of tests made by a British glass company, at the suggestion of Prof. Robert Newstead, of Liverpool University, England.
AN “ELECTRIC VIOLIN” has just appeared in Paris. Played by hand in the usual way, it has no sound box. Instead the tone of the strings is electrically amplified and made audible through a loudspeaker. The result, according to the inventor, Ivan Makhonin, is a pure tone, especially pleasing against a background of other instruments.
CORRECT exposure for amateur moviemaking is guaranteed by a new type of “exposure meter” that measures exactly how bright the light is in which the picture is to be made. It is so sensitive that through its use a photographer may select one exposure to bring out the shadows of a man’s face or another for the highlights, depending on the effect he desires.
So THAT manhole covers in city streets will not be blown skyward by explosions beneath them, G. W. Jones, explosive chemist of the United States Bureau of Standards, has developed a portable gas detector. It reveals in a few seconds whether the air beneath the manhole contains enough leaking gas to make it dangerously near the explosive point.
WHEN a man recently walked down a street in Barcelona, Spain, pushing a machine that left behind it a printed strip of advertising, civic authorities were aroused. What right did he have to paint advertisements on the city streets? Inspection showed they need not worry.
METAL rams, such as workmen use to tamp paving stones in place, are now used to find excavations made by prehistoric people. The method was developed by E. Cecil Curwen, British archeologist. Walled camps surrounded by ditches were left by primitive tribes in many places in England.
No NEED to crawl under a car in order to jack up a wheel, when a set of jackguides is installed. The guides, metal arms which extend ten to eighteen inches from the axle, are put in place by loosening the spring shackles, which are then retightened.
MARBLE forgeries, imitations of old masterpieces, may now be detected with the aid of ultra-violet rays. These invisible waves do not pass through glass, but when they encounter marble they so affect it as to give it a peculiar phosphorescent tinge, somewhat like that of a glowworm.
How the sun, nearly 93,000,000 miles away, creates a serious engineering problem for architects was discussed by F. C. Houghten and Carl Gutberlet, of Pittsburgh, before the International Heating and Ventilating Exposition at Philadelphia.
FLYING companies of machine gunners, able to dash from one point to another of a battle front and deliver a decisive blow, are presaged by the newest Army equipment—rapid-fire armament mounted on fast cars. It gives the Thirty-Fourth Infantry, which is stationed at Leehall, Va., for which it was designed, the first machine gun company of the United States Army to take to wheels.
SENSITIVE only to the particular kind of ultra-violet, or health, rays that have value in curing rickets and producing sun-tan, a new “electric eye” is the basis of a machine that automatically tells when a patient has had his daily dose of “sun rays” from a lamp.
HERE is a new way to send a greeting to a friend. Phonograph records on post cards have been made before, but now a German inventor has combined the record with a real photograph. The sender has his picture taken, records his voice on top of it, and the result is a personal record ready for the mail.
GROWTH of body cells throughout the animal kingdom is controlled by sulphur. This dramatic statement was made recently by Dr. Frederick S. Hammett, of the research institute of the Lankenau Hospital in Philadelphia, to the American Philosophical Society.
WHEN Army men recently decided to dig a seaplane-towing channel at Langley Field, Va., along an area where planes had been conducting bombing practice for many years, they faced a novel hazard. The ground had been struck repeatedly by bombs that failed to go off, and these “duds” had buried themselves several feet in the earth.
IN THE future, monster implements of war may be controlled from a distance by the mere turning of a radio dial. A Japanese army officer, Major Nagayama, has invented a means of directing by radio the movements of a tank able to travel at a speed of five miles an hour.
A COMBINATION pencil and knife recently has been designed. The flattened top holds a penknife blade, while at the bottom is a pencil of the regulation mechanical type. A penknife is less likely to be lost when it forms part of a device that clips into the pocket.
URANIUM, twice as heavy as lead and formerly one of the rarest of metals, is now available to scientists and experimenters at $400 a pound. Discovery of a way to extract the metal in a vacuum furnace made the new process possible. Dr. F. H. Driggs, research chemist of the Westinghouse Lamp and Manufacturing Company, declares. He recently exhibited plates and wires made of the rare metal. They were coated with a brownish color by the burning effect of the oxygen which is in the air, but when scratched they revealed the natural steelgray color of the metal.
A SUITCASE shaped camera, containing all the apparatus necessary for taking sound pictures, now takes the place of the cumbersome soundproof camera booth formerly used. It rolls about the movie studio on a chassis with large rubber-tired wheels, suggesting those of a primitive type of automobile.
WHAT would a rocket-propelled ship, capable of flying to the moon, look like? A scientific vision of such a craft is outlined by Dr. John Q. Stewart, associate professor of astronomical physics at Princeton University. It would be a massive, hollow globe—the outside studded with rockets to propel it through space, the inside a chamber where men would breathe an artificial atmosphere supplied from tanks.
TWENTY new kinds of pneumonia have been discovered in the laboratories of the New York Department of Health, to add to the three varieties already known. The result, according to the director of laboratories, Dr. William H. Park, is that new serums already have been prepared for many kinds of pneumonia which hitherto resisted treatment.
A QUARTER of a mile beneath the sea! That is the goal of William Beebe, noted explorer of the New York Zoological Society. From the portholes of a six-foot sphere of heavy metal, he will observe and photograph deep-sea life off Nonsuch Island, in the Atlantic Ocean near Bermuda, where he began studies last year (P. S. M., Mar. ’30, p. 49).
FEVERS made to order are the latest in medicine. A machine that gives a man a “radio bath,” and thus furnishes him a fever artificially, was demonstrated recently before the New England Physical Therapy Society. It was developed by General Electric Company engineers.
AN “IRON DOCTOR” for divers who come up too suddenly has just been perfected by the British navy. The device is a pressure chamber in which compressed air simulates the weight of water under which divers work. At great depths gas from the air dissolves in divers’ blood.
AN EMERGENCY rescue device for restoring victims of gas poisoning, which can be carried about as easily as a suitcase and does the work of two first aid men has just been adopted by the fire department of Birmingham, England. It applies “artificial respiration,” or forced breathing, automatically.
How much energy does it take to think? Recently Dr. Francis G. Benedict, nutrition expert of the Carnegie Institution, Washington, D. C., gave several subjects problems in mental arithmetic, and observed the amount of oxygen they used up in breathing—a measure of body energy.
HUGE airships several times as large but no heavier than those now constructed, higher towering skyscrapers, and bridges three or four miles long may be built in the future if methods can be devised for making the atoms of metals cling together more tenaciously.
SUMMER days, autumn nights, or almost any seasonal atmosphere may now be created in the home with all the ease of turning on the radio. This is made possible by the recent invention of a “homemade weather” machine. The apparatus can either warm or cool the air in the house, give it a thorough washing, or subject it to a drying process.
FLAWS in welded structures and other steel pieces that are in actual use may now be detected on the spot by three testing methods, each of which was demonstrated recently at Lehigh University, Bethlehem, Pa. The methods call into use three distinct scientific discoveries—the principle of electromagnetic induction, the physician’s stethoscope, and the X-ray.
FOOTBALL fields, polo grounds, and areas of turf that require stamping need no longer present a labor problem if a new machine shown in Leipzig, Germany, is all that it is said to be. This novel “earth beater” does away entirely with the need for human effort.
A SWEET that doesn’t fatten is the United States Bureau of Standards’ latest contribution to the sugar industry. The new sugar, known as “xylose,” sweetens food but is not assimilated by the body. Through a new process, it may be produced for little more than five cents a pound, the actual cost of extraction.
RAPID and unerring examination of pearls is now performed with a “pearlometer,” an instrument devised by an Austrian inventor. It consists of a huge binocular (doubleeyed) microscope equipped with an unusually powerful light apparatus for laying bare the innermost heart of a pearl.
Colgate University tests offer startling proof of man's dependence on sweet.
JAMES W. BOOTH
IS OLD MAN PAR too much for your golf game? Are you too slow on the trigger when the traffic lights change from green to red? If so, the chances are that you don’t eat enough sugar. The man who makes a hole in four while his opponent takes five or six, does so because of a well-balanced coordination of mind and muscle.
Twenty years in airplanes failed to give a veteran pilot the thrill he got when a sailplane carried him on the wings of the wind.
"THERE’S where we'll hop off,” Hawley Bowlus told me. He pointed to the top of a 165foot ridge. It lay between the pounding Atlantic and the gray waters of Long Island Sound. We were near Montauk Point at the eastern tip of Long Island. I was about to make my first flight in a soaring plane, in the ship that Lindbergh flew and which POPULAR SCIENCE MONTHLY had bought for me to fly.
THE United States has lost its world leadership in inventive progress. This, at least, is the conclusion one is bound to reach through a study of United States Patent Office statistics and a comparison of these figures with those of foreign countries.
ONE man controls the power of a million volts, in the new high-tension testing laboratory just opened by the Metropolitan-Vickers Electrical Company at Manchester, England. A touch of his fingers releases a blinding inferno of electric flame from great copper balls suspended in the testing room.
GERMANY, England, and France are hotly contesting the leadership in the movement for the ultra-modern in architecture. So far Germany rather leads the race, but the steel houses, now being erected outside of Paris, are evidence that French architects are making a strong bid for first place.
COMFORT and better eyesight are claimed by the inventor for those who wear lenses inside the eyelids instead of in the usual “outside” spectacles. The new glasses, devised by a German oculist, are an adaptation of the thin glass shells sometimes used to protect the cornea in cases of inflammation.
WHAT happens to a living cell of animal or vegetable matter when it is whirled at from 2,000 to 3,000 revolutions a minute can now be seen through a microscope. The apparatus that makes it possible is the invention of Prof. E. Newton Harvey, of Princeton University, and Alfred L. Loomis, bankerscientist of Tuxedo Park, N. Y. Biologists are interested to know the structure of a cell, its toughness, and the relative density of its parts.
TROLLEY transportation entered the competition always going on among high speed passenger vehicles when twelve new street cars, capable of sixty miles an hour, were added recently to the West Penn System in the Allegheny Valley. The cars are so designed that their highest operating efficiency is better than forty miles an hour.
SNAKE bites, diphtheria toxin, lockjaw, and mushroom poisoning may all be combated by hypodermic injections of various spring waters, according to Dr. Gustave Monod of the famous mineral spring resort at Vichy, France. In a recent report to the Hunterian Society in London, Dr. Monod outlined discoveries made by the late Professor G. Billard of the Clermont Ferrand medical school, France.
SHIMIZU TUNNEL, longest in the Orient and seventh longest in the world, drilled through the mountains of western Japan, is nearing completion. The tunnel, 31,831 feet or slightly more than six miles long, is more than 2,000 feet above sea level for its entire length, and cost $6,000,000.
MOUNTAINS, canyons, and plains of the United States are seen in startling prominence on a huge relief map rapidly taking shape at the Babson Institute, Wellesley, Mass. It is said to be the largest of its kind. From the Atlantic to the Pacific coast, the map measures sixty-three feet.
THE strength of welded joints in trolley tracks gets a gruelling test at the United States Bureau of Standards, at Washington, D. C. A section of rail, held between two anvil-like supports, is rapped by a mighty 400-pound hammer once a second for as long as the rail will take the punishment.
NECKTIES of rubber are a novelty in France where they are declared to be attractive and practical. Sheets and threads of rubber are woven together in the French process, making a material resembling either silk or cotton at will. Any color scheme may be used upon the rubber ties, which are made both in bow and four-in-hand shapes.
ON A crack express train of the Canadian National Railways, speeding at more than a mile a minute, a passenger talked by telephone with London the other day. The occasion was the inauguration of two-way telephone service from moving trains as a standard part of the railroad’s equipment.
ONE million tons of rock are to be excavated in drilling a colossal vehicular tunnel now in the process of construction beneath the Mersey River in England. The tunnel will connect Liverpool with its companion city of Birkenhead on the opposite bank.
EACH day 8,000 tubes of vaccine and 12,000 tubes of serum leave one of the greatest centers of preventive medicine in the world—the Pasteur Institute, in Paris. It was founded by national subscription nearly fifty years ago as a laboratory for the great French chemist, Louis Pasteur, father of bacteriology.
A GIGANTIC cylindrical caldron that fills with gas and holds a railway car inside it is the remarkable expedient used by the German Federal Railway to kill bacteria and vermin. After a car has been in service for a certain number of miles, it is brought to this fumigating plant.
BECAUSE his clothing might deaden the sounds of voices just a little, an engineer at the United States Bureau of Standards’ new sound laboratory sits in a box. The laboratory is a miniature theater, where the acoustics of “talking movie” installations may be tested.
ONE of the most remarkable of chemical elements is helium, the inert gas used to fill balloons and dirigibles. Although most people think of it in that connection, it has various other extraordinary uses. If a man with a deep “basso” voice should fill his lungs with helium, for instance, his voice would change to a high tenor.
THE world’s most powerful magnet has just upset classical ideas of the way electricity runs through wires. So the Russian engineer who built it, P. L. Kapitza, recently reported, in describing the researches he had made at Cambridge, England.
BEEHIVES, bathtubs, and garden furniture are now made from roots of the palmetto tree, a small palm of the southern United States. By grinding the palmetto roots and mixing them with cement of a special formula C. P. Wilhelm, of Punta Gorda, Florida, produces an extraordinary material which is said to be as light and as tough as wood, impervious to water, and as enduring as concrete.
NEW potatoes can be served all the year round, through a canning process put into use a short time ago at a plant in Florida. Sweet potatoes have been put up in cans for some years, but the ordinary “spud” has never been canned on a commercial scale.
GARDENERS of the coming era may possibly rely on a novel variety of fertilizer—radio waves. Successful cultivation of certain vegetables in one half the time ordinarily required through stimulation by radio has been reported by a German physicist, Dr. Fritz Hildebrandt.
A NEW gas called “electrolene,” produced in a special electric machine, takes the place of hydrogen gas for welding torches and brazing furnaces. Made from steam and city gas, it costs only one tenth as much as hydrogen. The machine that generates the new gas, developed by the General Electric Company, looks like a cylindrical boiler.
“TALKING MOVIES” recorded the latest total eclipse of the sun from an Army airplane over Claremont Field, Calif. Never before had this been done. The definite scientific object of the feat was to determine, more accurately than could be done with stop watches, the exact moment of each phase of the eclipse.
F. TRUBEE DAVISON, Acting Secretary of War, recently authorized the Quartermaster General to procure for a service test “one mechanical substitute for an Army band.” The “mechanical substitute” is a three-quarter-ton truck which carries a phonograph and powerful amplifiers, developed by the Radio Corporation of America.
A DIESEL or oil-burning motor, in a waterproof compartment, drives the latest “unsinkable” lifeboat. The new type of life-saving craft has been installed on the speedy transatlantic liner Bremen. In a recent demonstration at a Brooklyn, N. Y., pier, 148 persons piled into one of the boats and it was lowered to the water. Then the occupants staged a mock panic, crowding first at the fore end and then at the stern, as excited victims of a sea disaster might conceivably do.
How tough is a piece of meat? One of the first instruments ever devised to test it accurately was recently installed at the United States Bureau of Standards, at Washington, D. C. A metal disk mounted on a board between a blunt knife and a crank handle, and attached by chains to both, records the force needed to draw the knife through a sample of meat by turning the crank handle.
Two “enemy” submarines, approaching the Golden Gate apparently with the intention of destroying ships in San Francisco harbor, were sighted the other day by an Army transport plane. Five minutes later, Army men at Sacramento, eighty miles away, held in their hands a brown-and-white map revealing the submarine’s position and bearing a recommendation that an air bomber be sent after the subs.
AN “AQUATIC BUTTON,” a sort of miniature seadrome shaped like a saucer cut in half and inverted, serves as a landing field for amphibian airplanes on the busy San Francisco water front. The device is a semicircular stage 100 feet in diameter, with sloping edges submerged.
DEVICES FOR FLYERS INVENTED BY STUDENTS WHO CAN’T FLY
ONE test of a student’s flying knowledge is his ability to build aviation instruments. So embryo pilots of the Boeing school of aeronautics, at Oakland, Calif., have constructed the devices pictured above while they are learning to fly on the ground.
THE first transatlantic mail by airplane arrived in Brazil recently. It was brought by Jean Mermoz, French pilot, and two companions, who made the 2,000mile water jump from Africa to South America in a seaplane flight of twenty hours. The flight was authorized by the French government as a test of the practicability of sending mail by plane, after Mermoz had proved his ability to land his plane on rough seas.
LIKE a playing card falling from a skyscraper, Lieut. Alford j. Williams, crack naval pilot, fluttered to earth in an upside down plane the other day at Washington, D. C. Thus he performed a maneuver called the “inverted falling leaf,” never tried before because it had been declared impossible to escape from it alive.
LESTER N. YOHE, college freshman and member of the Penn State Glider Club, at State College, Pa., set out to design a glider that would soar forward more than the conventional twenty feet while dropping one foot in the air. He built a model with a fuselage of concave bottom.
SMOKE tells pilots the direction of the wind in a new invention for airports, which replaces the usual cone of fabric that swings from a pole. Burning crude oil, this new smoke pot can be run for only thirty cents daily. Installed in the center of the air field, the stream of white smoke it pours out is visible two thousand feet in the air, revealing the wind direction and aiding pilots in landing.
Now being designed in the Rumpler factory, at Berlin, is the largest airplane in the world. It will have a wing spread of 289 feet, or more than the length of a city block, and it will be 160 feet long. Called a “flying wing,” because passengers are carried within the hollow wings instead of in a fuselage, it will have a cruising radius of approximately 5,000 miles with a full passenger load of 120 persons aboard, and can carry a pay load of twenty-one tons.
ASLENDER spire of rustless steel tops the 1,046-foot Chrysler Building, in New York City, which officially opened a few weeks ago. Many of those who see the shaft gleaming in the sunlight wonder how it was placed at the summit of the world’s tallest building.
SIX o’clock of a stormy spring evening. Fire breaks out in the Ohio State Penitentiary at Columbus. Five thousand men fight for their lives behind melting prison bars. Three hundred and seventeen are killed in their cells by flames and suffocation.
TORN and twisted, an ocean cable last winter lay buried under a layer of clay two miles beneath the graygreen, foam-capped waves of the Atlantic, three hundred miles east of Halifax. It was shattered by the terrific earthquake that shook the Atlantic seaboard for a distance of 1,000 miles and put out of commission about half of the underwater communications between the United States and Europe.
AMERICA’S only planetarium, a million-dollar project, was opened recently on an artificial island in Lake Michigan just outside Chicago. A planetarium is a building in which points of light, representing stars and planets, are projected against a dome by means of illuminated stereoptican slides to show spectators the movements of the heavenly bodies.
A STONE-CUTTING school, said to be the only one of its kind in the country, is supported by prominent society people in the famous artisans’ center of Greenwich Village, New York City, for instructing talented children. Like young apprentices in the care of the sculptors who carved the stonework of the great medieval cathedrals, these ambitious children receive routine drill in the technical mysteries of sculpturing stone.
SWALLOWING bitter medicines may be made less unpleasant by taking them in the guise of sea foods and other dishes, suggests Dr. Rene Loubatie, of Bordeaux, France. As an example he cites the inoculation of oysters with iodine, the chemical element that is vital to the activity of the thyroid gland.
EXPERIMENTS have convinced a Spanish physician that wines and other liquors give a greater “jag” when sipped slowly. Dr. Jose Calleyaz, of Madrid, searching for the best way of giving stimulants to patients in a state of collapse, found that if he administered the alcohol drop by drop into the patient’s mouth, he got prompt effects.
MASTS PLAY BIG PART IN AMERICA’S EFFORT TO DEFEND YACHT CUP
WHEN builders were called upon to fit America’s four cup defender yachts with taller masts than ever seen before, they solved a problem unique in marine design. These boats, of which the fleetest one will defend the famous America’s cup against Sir Thomas Lipton's Shamrock V next September, will all have spars more than 160 feet high (P. S. M., July ’30, p. 61).
Six men, each six feet tall, standing on top of each other would only just reach from the floor to the top of a gigantic press recently completed at a mid-western plant for stamping the frames of auto trucks. The slightest turn of the huge wheels that work the mechanical monster causes a pressure of 3,500,000 pounds, the weight of a large freight locomotive, to be exerted at the bottom.
SOON the State of Michigan will open a high-power radio station to help police catch crooks. Authority for the 5,000-watt installation at Lansing, Mich., has just been granted by the Federal Radio Commission. State patrol automobiles carrying radios will be able to pick up the station from any point in the state.
A NEW invention for amateur astronomers is said to make self-instruction in the secrets of the skies easy and absorbing. It is a homemade planetarium, which reproduces in miniature the dome of the heavens, showing the planets and constellations mapped out in their proper positions.
How far talking movies have swept silent pictures from the screen is revealed in figures recently given the Society of Motion Picture Engineers. They show that at least 5,500 theaters—three fourths of all the motion picture theaters in the country—will be wired for sound reels by the end of 1930.
THE haunts of the marine underworld are an open book to Dorothy Beck, an amateur artist from Livermore, California, who is sketching as many scenes of sea life as possible during her round-the-world trip. She has merely to place her big wooden periscope in the water in order to bring before her eyes a moving picture of activities of marine life.
HAILSTONES that did a million dollars’ damage in Moundsville, W. Va., a year ago last March, are still in existence. A dozen of them may be seen today in the ice cream cooler of a Moundsville store. Placed there after the storm, they have been kept by electric refrigeration as large and firm as when they fell.
BATHING fashions in the course of centuries have seen many novelties, but it remained for a Los Angeles, Calif., designer to think of this new headgear, which is a combination cap and face mask in one. When the first wearer recently appeared on the Los Angeles beach, the startling, round eyeholes of the mask might have suggested to a fanciful observer the appearance of a feminine Martian or a lady robot.
TWO articles in this issue are so clearly illustrative of our method of gathering news and facts for you that we cannot resist pointing out the story behind them. Some time ago we suggested to Assen Jordanoff that he write for us a comparison of flying in gliders and in power airplanes.
Reception late at night calls for silence, and headphones come into their own. With most sets loudspeakers can be disconnected and earpiece attachment made at binding posts. Hook-up when you can’t reach voice coil.
ALFRED P. LANE
IN THE early days of radio there were few loudspeakers and no good ones. Everybody listened with the aid of headphones, and illustrations of the newest sets of that period usually pictured several people attached to the receivers by headphones.
Changing Current Gives Bad Reception and May Ruin Tubes. Temporary Repairs of Audio Transformer
SHORT CIRCUIT TESTS
A B C’s of Radio
THE electric light current supply in this country, from which electric radio sets draw their power, is nominally rated at 110 volts. This is the standard electrical pressure the power companies try to maintain. Unfortunately, however, the actual voltage at the wall plug to which you connect the radio set is practically never exactly 110 volts.
Shiny Outside Means Little—What Counts Is Durability of Electron Producing Filament
WHEN you go to buy a vacuum tube the chances are you tell the clerk the kind of tube you want. He picks one off the shelf, unwraps it, and sticks it in the socket of the test outfit. After the tube lights up he turns various switches and presses some buttons with the result that the pointers on the dials of the test set wriggle back and forth.
MANY readers of POPULAR SCIENCE MONTHLY have asked me if Gus Wilson is a real, live man and if the Model Garage actually exists. The answer to both questions is yes. The Model Garage is located in a town not far from New York City. It is owned and operated by two men whom I have named in my stories Gus Wilson and Joe Clark.
I HAVE been wondering for some time just how much you, the readers of POPULAR SCIENCE Monthly, actually know about what goes on under the hood of an automobile; whether you choose your cars by the looks of a fancy paint job or a stylish body, or whether you pry into the innards of the car to judge the merits of the machinery that makes it go.
Making a full-rigged model that folds so as to enter the neck
$100 IN PRIZES
E. ARMITAGE McCANN
"HOW did it get there?” is the question always asked when a ship model in a bottle such as shown in Figs. 2 and 3 is placed on exhibition. You will observe the curious minded examining the bottom of the bottle to see where it was cut to admit the ship, or they will even inquire if the bottle was blown around the ship.
An expert’s impressions of a new type machine, and a built-in Colonial corner closet design
WILLIAM W. KLENKE
HAVE we been doing our machine sawing upside down? I wonder—and so will you before you finish reading this article. Let’s review for a moment a previous article on “Mastering the Use of a Circular Saw” (P. S. M., Nov. ’29, p. 88). Note how all the cutting is done from the underside.
HOW many of the fundamental facts concerning house repairs, finishing, painting, lathe work, and general wood and metal working have you at your finger tips? The multiple choice questions below are designed to test your knowledge of a few of the handy man’s A B C’s.
BEFORE out on Rear his great Admiral adventure Byrd started to the South Pole, he had, with his characteristic foresight, provided plans not only for his camp buildings, but also for the furniture they were to contain. Now that the camping season is upon us, it behooves us likewise to plan in advance so that our vacation at the summer camp or cottage—be it by the sea or mountain lakes—will be pleasant and comfortable.
ABOUT the simplest of all shop operations is that of putting a round hole through sheet metal. You have your choice of punching it or drilling it. And yet again—it may not be quite so easy. Presses have a habit of being tied up when you need them for smaller jobs; and for each size of punched hole, there must be a punch and a die.
Axle wedge stops shimmying. Rim spreader is easy to make. Door locks to guard children.
SHIMMYING are due to a slight and hard inaccuracy steering in often the setting of the king-pin angles. If the king-pins are too nearly vertical, or the king-pins actually lean forward instead of backward, the wheels will not have the proper tendency to straighten out by themselves after rounding a curve.
IF, THROUGH wear or an accident, one of the connecting lines to a hydraulic brake leaks or is broken off, no pressure can be applied to the other brakes. Under such conditions, the temporary repair shown in Figure 2 will render the three remaining brakes operative.
THE device shown in Figure 3 will prove serviceable in mounting tires on rims of various sizes. It consists, as shown, of a wooden platform in which three rings of holes are bored part way through. Four-foot lengths of iron pipe are strung together with a wire through holes in the pipe as shown and the top disk is notched to support the other ends of the pipes.
IT IS customary to make the doors of equal width on the ordinary twelve by eighteen foot home garage. With doors of this width it is necessary to open first one door and then go back and open the other one. If one door is made extra wide and the other narrow, as in Figure 4, time is saved because the narrow door can be pushed all the way open even in a strong wind, while a hold is still retained on the other.
WHEN children are carried in the back seats of cars fitted with four doors there is always a chance that one of the children may pull open the latch of one of the rear doors and fall out. Figure 5 shows two ways to prevent this trouble. The view at the lower left shows a strap arranged to hold the door latch in a closed position.
MANY amateur mechanics have learned by experience the difficulty of hanging doors, especially large ones, with ordinary butt hinges, because of the accuracy with which the hinge mortises must be marked and cut. Hinges are now available which have much the same appearance as regulation butts and yet require no mortising; they are therefore very easy to apply.
NO MATTER how small a garden may be, there is always room for a rock pool. Properly planned and set in a background of wellchosen plants, it is a source of joy to the owner and of admiration to his friends. Pools may be round, elliptical, kidney shaped, or made to fit the contour around large boulders or trees.
WITH ordinary ink and a pen it is possible to write distinctly on glass. One advantage of this process is that the ink, being very dark, stands out strongly against the transparent glass. Sometimes the ink will take on unprepared glass without blurring, and this is especially true if the glass has been rubbed with the fingers or if it has been covered with a little saliva and allowed to dry.
EVERY machinist and toolmaker knows that the graduations on the feed screw dials of ordinary milling machines and boring mills cannot be depended upon for the close limits desired on such work as boring jigs. If, however, the machine is in fairly good condition, it is neither difficult nor expensive to rig up an arrangement whereby the dimensions can be held as close as humanly possible, which is about plus or minus .0001 or .0002 in., provided the preliminary drilling and boring operations are done with the utmost care.
THE problem of storing small quantities of sensitized blueprint paper becomes an easy one when you provide yourself with a suitable tube container similar to the one to be described. The tube portion of the container can be made from a piece of paper tubing such as furniture and rug companies use in rolling rugs for shipment.
AN ANGLE plate gripped in a vise will serve as an excellent surface plate for small work. Always drill and ream a hole at one setting, if it is possible. Remove as much metal as you can with a drill and a power hack saw before placing the work in the miller.
REPRESENTING the little white house with the green shutters where the three bears lived and the scene of the familiar fairy tale, the chair illustrated forms both an attractive and durable piece of furniture for either the nursery, playroom, or child’s bedroom.
You do not have to be an expert to design and make
EDWIN T. HAMILTON
FEW model builders, if I may venture an opinion, have mastered the art of designing and cutting truepitch propellers. On recent inquiry, I find that this is due to a mistaken belief that no one but an aeronautical engineer can understand propeller mathematics.
BECAUSE of the keen interest displayed everywhere in the sport of gliding, a Bowlus sailplane has been chosen for the subject of the fifth article in the present series on constructing simple, nonflying models of modern planes. There are so few parts that the model should not be difficult for anyone to make, yet when neatly finished and carefully painted, it will be a unique and worthy addition to the models previously described (see P. S. M., Apr. ’30, p. 110; May ’30, p. 124; June ’30, p. 95; July ’30, p. 76).
Ten Suggested Designs That You Can Construct Easily at Trifling Expense
GEORGE VAN WALTHER
BY USING the ten ornamental trellis designs shown as a basis for construction, the home worker should encounter little difficulty in supplying his garden with a variety of fences, screens, and attractive supports for climbing vines, flowers, and shrubs.
How may doors for a bookcase or other shelving be built?
What are some simple methods for constructing adjustable shelves?
When shelves of the skeleton type are required, how may they be built?
How may hanging shelves be made and hung?
How are shelves finished?
C. A. K
TO CONSTRUCT the best type of shelving for any special purpose, the handy man must be familiar with a wide variety of designs. Suggestions are therefore given in this article for building a bookcase of a superior type, with or without doors, and for making adjustable, skeleton, and hanging shelves.
There’s an Air Mattress Hidden in This Sleeping Bag
L. C. NODERER
SUCCESS and pleasure in camping depend upon carrying the largest amount of comfort in the smallest and lightest bundle. That is why the sleeping equipment presents one of the most stubborn problems. Ordinarily, it is necessary either to take a cumbersome outfit which includes a folding bed, mattress, bedding, and tent or to go to the other extreme and sleep on the hard ground, unprotected from the elements.
HERE are two more block-puzzle teasers. They can be made in two sizes, the parts being either ½ or ¾ in. wide and of any desired thickness. In cutting the letter-A puzzle from wood, you will need a miter box marked in degrees, because the cuts must be accurate.
BELOW are given the correct answers to the home workshop questions given on page 75. The wrong word or terms have been left out in each sentence. 1. The teeth on a crosscut saw are beveled. 2. Direct current should be used in plating and similar electrochemical reactions.
WHEN the grain of your razor strop has become “filled” with oil, dirt, and the wear of steel blades, and will no longer give the service for which it was intended, it can be renovated at no cost whatever and within two minutes’ time. Turn the fine edge of an old blade by drawing it, under pressure and at about a 45° angle, across a bottle-neck.
TO ENCOURAGE a friendly competition among model makers, POPULAR SCIENCE MONTHLY will give $100 in cash prizes for the six best ship models built in bottles according to the general method described by Captain McCann. The awards will be as follows:
AS TO what to do when the paint is still tacky at the time of repainting— in some cases a mixture of three fourths turpentine and one fourth drier will dry up the sticky paint. In other cases, a coat of aluminum paint will serve.
DOES it pay to build your own trailer? That is the question I asked myself—and the answer is the trailer illustrated, which cost $23.30. My object was to build it both substantially and economically. The angle iron for the framework and the curved brace on the front were obtained from an old iron cot.
IN REMOVING varnish or other finishes after they have been softened with a commercial remover, a liberal supply of sawdust may be used to soak up the old finish instead of rags or excelsior. After most of the finish has been removed, the surface is brushed briskly with an old whisk broom or coarse brush to clear away the dried particles from the work.
Providing Your Hunting Knife with a D urable Sheath
F. CLARKE HUGHES
EVERY hunting knife deserves a good sheath, whether it is a homemade knife, such as was described in a previous issue (P. S. M., July ’30, p. 116), or a commercial knife, the sheath of which has been lost or worn out. It is not difficult to make a durable and neat looking sheath from three small pieces of good grade sole leather and a few split rivets.
TO ASSIST you in your home workshop, POPULAR SCIENCE MONTHLY offers large blueprints containing working drawings of a number of well-tested projects. Each subject can be obtained for 25 cents with the exception of certain designs that require two or three sheets of blueprints and are accordingly 50 or 75 cents as noted below.
Swing, horizontal and parallel bars, rings, and trapeze in one combination
CHARLES A. KING
WITH its five varieties of apparatus, this easily constructed combination forms a complete gym for children up to twelve years of age. The horizontal bar, trapeze, and rings can be adjusted to suit the skill and experience of each young athlete.
These Six Practical Hints by BERTON ELLIOT Will Insure a Durable, Good-Looking Finish
UNLESS paint is properly mixed before it is used, it cannot be expected to give good results. Stirring round and round in the manner shown at the left will not mix paint thoroughly, and attempting to stir a full can will generally result in the spilling over of a good deal of the oil.
A CONVENIENT folding rack for drying a few small articles indoors can be made as illustrated in the accompanying photographs from stock wooden dowels, a piece of webbing, six large screw eyes, and two rivets. The stand opens up scissors-fashion and is intended to stand in the bathtub.
BEFORE attempting to repair a small leak in a pan or kettle, rub the spot around the hole inside the dish with emery cloth or other abrasive until bright. Place the hot copper under the hole to heat the metal. Rub the upper side with flux, then apply a drop of solder.
STRANGE sounds like the distant boom of guns have been heard again this year across Lake Seneca, N. Y. The “lake guns,” of which examples are known all over the world, have never been satisfactorily explained. Scientists have established only the facts that they are not thunder and are not of human origin.