A Four Square FINANCIAL PLAN for a YOUNG MARRIED COUPLE
THE Financial Department’s mail at the POPULAR SCIENCE MONTHLY office contains many letters relating to interesting financial plans and problems such as everyone confronts. We are yielding to the temptation to publish one of these letters together with our reply as we believe the subject will stimulate the thoughts of every reader who is seeking a sound program for his personal finances.
THIS Financial Department is to help readers in the establishment of proper financial programs at the beginning of their usiness careers; it assists those who have accumulated money in the proper investment of it. The Editor of this Department is an authority on investment matters.
TO AID readers in their buying problems, to determine that only reliable products were being advertised and to make POPULAR SCIENCE MONTHLY a still better magazine—these were the three aims the publishers had in mind in establishing the Popular Science Institute of Standards.
Press a button, and the airplane engine roars into action! This new selfstarter for airplanes, invented by C. F. Heywood, of Detroit, Mich., makes it unnecessary for a mechanic to spin the propeller by hand. Compressed air controlled from the pilot’s cockpit turns over the engine.
A wonderful new light designed to guide airplanes safely to their landing fields in bad weather gives off intense orange-red rays from the huge electric tube shown above. These rays, because of their long wave length, are said to penetrate heavy fog.
The latest development in gearless motor cars, the recent invention of James Fraser, of Glasgow, Scotland (at the right), is based on the turbine principle. The engine has a series of revolving blades which, through the medium of a liquid, transmit the motor's power to another series of blades connected with the rear axle drive
This picture shows Gar Wood’s speedboat, Miss America V immediately after setting a new world’s salt water speed record of 80.46 miles an hour at Miami, Florida. The famous speedboat pilot is seen at the wheel
To study the wonderful formation of the famous Natural Bridge at Staunton, Va., Dr. Chester A. Reeds of the American Museum of Natural History recently was let down from the top of the arch, which is fifty feet higher than Niagara Falls. At the left he is seen at a height of about 200 feet
Clear the tracks; here comes the vacuum cleaner! Walter M. Spring, research engineer, is the inventor of this strange apparatus for cleaning cinders and refuse from trap rock roadbeds. It consists of three huge suction chambers, the bases of which run close to the track bed.
It looks like a fierce naval engagement. Actually, though, the remarkable picture in the circle shows what happened recently to the rum ship W. T. Bell at the moment Coast Guardsmen blew her up with a hundred pounds of TNT on the beach at Bayville, N. Y. With a deafening roar, showers of timbers were hurled skyward, while billows of smoke drifted out over the sea.
Every inventor’s dream of a million-dollar idea has just been realized by Anato1 Josepho. This young Russian photographer recently received that sum for his remarkable automatic photographer, previously described in POPULAR SCIENCE MONTHLY.
Ideas borrowed from Zeppelin construction are embodied in a revolutionary type of express cruiser built in Germany for Otto H. Kahn, prominent American financier. From stem to stern the hull is reinforced by a metal framework of the light alloys used in building airships.
Like a naval cannon in appearance is a “gun” searchlight just perfected for use in a new form of sky-writing. Advertising matter inserted between the lenses in the barrel of the cannonlike projector is thrown in gigantic letters and pictures upon overhead clouds.
A Naval Officer's Vivid Story Revealing Inside Workings of a Submarine
THERE was a touch of mystery to the scene: two ships at a dead stop in the center of an otherwise empty ocean; weather clear as a bell; fresh breeze out of the north’rd; sea sparkling in the June morning sunshine and flecked with whitecaps. The kind of day when ships should be about their business.
Giant 1,000-H.P.Auto Demonstrates New Racing Principles
H. C. DAVIS
“I WAS going so fast I couldn’t look at the speedometer! To guide the car, I had to focus my eyes half a mile ahead. If I had looked at the dial for an instant I might have lost control. I didn’t know the car had made 200 until after the run.” The British speed king, Major H.O.D. Segrave, was describing his recent experience in driving his mammoth Sunbeam racer, the Mystery S,over the sands of Daytona Beach, Fla., for a world's record of 207.01 miles an hour.
Studies of Luminous Insects, Fish and Bacteria May Yield Key to More Efficient Lighting of Our Homes
SCIENTISTS are on the verge of far-reaching discoveries which eventually may make the incandescent electric light as out-ofdate as the old-fashioned kerosene lamp. They are learning the secrets of a lighting system used by Nature for ages, yet always a mystery to man—the production of light without heat.
“Sea Hawk” Rivals the Birds in Speed Range and Control
ONLY six feet of air separate the plane from the ground. Motor roaring, it flirts with the earth. Gracefully, lazily, it skims closer, throttled so slow that a fast motor car could outdistance it. It touches—rises again, wheels spinning from the contact—and airily circles the field.
Experiments with Pumpkins, Teast and Rats Make Possible Forecasts of Cities’ Growths
How Your City Will Grow
MYRON M. STEARNS
THEY were weighing a rat in one of the research laboratories of Johns Hopkins University at Baltimore. Weighing it with particular care, for a strange reason—to find out what the population of New York City would be in 2000 A.D.! The study of a rat’s growth came in the course of an investigation by Dr. Raymond Pearl, Director of the Institute of Biological Research, at Johns Hopkins, by means of which he has demonstrated that the increase in population in a given region or country over a particular period of time can be foretold with almost unbelievable accuracy.
Engineer's New Control Tube Runs on a Billionth-Watt
A GOLD watch lay on a plush-covered table in a New York hotel. Near by was a small glass bulb. A man extended his hand to the watch; but even before he could touch it, an electric alarm rang. A lighted match was held between the thin wires connected with the bulb.
CHEAPER electricity for all of us, because it can be transmitted economically thousands of miles where only hundreds have heretofore been possible, may be one of the results of a new system of handling electricity perfected by Frank G. Baum, San Francisco engineer.
Motor Cars, Airplanes and Modern Machinery Mark Latest Stampede for Gold in Nevada
EARLY this spring two nineteen-year-old boys, prospecting in the barren hills of Esmeralda county, southwestern Nevada, ran upon a badger hole. They dug into the hole. At the bottom, instead of a badger, they found a ledge of rocks shot with streaks of gold.
"THE present is only the very beginning of an age of diseovery—and the next century will mark the greatest advance of civilization in the world’s history.” So says Prof. A. M. Low in his new book, “The Future,” a tale of wonders such as no fairy tale ever presented, of the marvels science has in store for the future.
The first hydroaeroplane—Ship-to-shore flights—Other triumphs of Glenn Curtiss, air pioneer
FRANK PARKER STOCKBRIDGE
ENTHUSIASTIC delegations met Glenn Curtiss at the pier when he returned from Europe. His victory at the first international aviation meet in France had fixed him as a national hero. All America now wanted to see him fly. Scores wanted him to build flying machines for them.
These Fifty-Eight Questions Offer a New Way to Test Your Stock of Useful Information
Terms of Applied Science
Inventors and Inventions
Mental Measuring Stick
Application of Measurements
HOW large is your stock of useful information? Have you learned the secret of selecting valuable facts and figures from the general run of information, and of sorting them in mental pigeonholes for future reference? Or have you allowed knowledge, once gained in school or elsewhere, to escape you through neglect or disuse?
Noted British scientist's remarkable experiments with athletes have revealed many amazing new facts about the mechanics and chemistry of running
WHEN Charles W. Paddock, the California sprinter famous as “the fastest human,” not so long ago ran 100 yards in 9 5-10 seconds, he established a new American record, clipping one tenth of a second off the mark set by Arthur Duffy a quarter of a century ago.
ASTRONOMERS from all over the world are gathering in Norway to view the total eclipse of the sun that will occur early in the morning of June 29. The United States, where memories are still vivid of the eclipse of January 24, 1925, is to send at least one party to study the eclipse, the McCormick-Chaloner expedition from the University of Virginia.
THE ventilating system installed in the new Hudson River vehicular tunnel connecting New York and New Jersey has been, perhaps, the most important of the stupendous problems involved in this great engineering feat. If the ventilation is not adequate in a tunnel designed to carry motor vehicles, there is a possibility of serious injury to the health of drivers using the tunnel.
THERE is no such thing as a “criminal type,” we are now told. The average criminal is a normally intelligent individual, and consequently our methods of punishment, which are based on the theory that he is a “type” and not an individual, are doomed to failure.
ARCHAEOLOGISTS, digging into the soil of America, have recently come upon fascinating evidence that men lived on this continent far earlier than has been generally believed—perhaps a million years ago! This evidence, gathered by J. D. Figgins and Harold J. Cook of the Colorado Museum of Natural History at Denver, consists of arrowheads and other implements found buried with the fossil bones of extinct animals in ancient geological deposits in Oklahoma, Texas and New Mexico.
DISCOVERY of a new anaesthetic, said to have important advantages over ether or chloroform, is claimed by German surgeons. Known as “107,” it has proved successful in 300 tests, according to Dr. Ernst Unruh, of Berlin. Under its influence, pulse and blood pressure of patients are said to remain normal, disagreeable after-effects and danger to heart, lungs or nerves eliminated, and operations possible even in severe cases of pneumonia and advanced tuberculosis.
WE SHOULD find it hard to get along today without rubber; yet its countless uses would have been impossible without the ceaseless work of chemists. Dr. W. C. Geer, one of America's foremost rubber experts, recently stated that the world owes a billion dollars a year to chemistry in the rubber industry alone.
INVENTION of labor-saving devices in industry is being more than ever stimulated by the decrease in the supply of “cheap labor” in this country, says Prof. Robert D. Ward, of Harvard University. “From one end of the country to the other, reports of new labor-saving machinery are coming in almost daily.
NO TWO things in the world are exactly alike, we are often told. A close approach to duplication, however, is found in the case of “identical" twins; that is, twins believed to have grown from the sanae fertilized egg cell, as distinguished from ordinary or “fraternal” twins.
SCIENTISTS at the University of Helsingfors, Finland, have just completed interesting measurements of tlie energy Consumed in dancing, in terms of heat units. The fast mazurka consumed the most fuel—10.87
REGARDING future development of natural resources, Secretary of the Interior Hubert Work says: “Science can help us find new wealth in materials trodden under foot as worthless.” A dirty yellow mineral found on barren slopes of Colorado proved to be radium, boon to the suffering.
IN THE blood stream. pumped from the heart to give us life, there are daily tides, like the ebb and flow of the tides of the sea. Dr. A. F. Bernard Shaw, of Newcastle, England, recently made this discovery while studying the white corpuscles of the blood.
JUST because a person is descended from hard-drinking ancestors is no sign that he can “hold his liquor” better than others; nor does it mean he is more likely to turn into a drunkard. Such are the conclusions of Prof. Frank B. Hanson and Miss Florence Hays of Washington University, St. Louis, Mo., after staging a series of drinking tests with rats.
AN INTERESTING new fact about radio broadcasting has been revealed by R. H. Barfield of the English Radio Research Board. It is this: The strength of a signal received on your set depends materially on the number of other radio listeners tuned in.
CRUISING among the Aleutian Islands, four Seattle yachtsmen—Parker and Thornton, partners in an engineering firm; Williams, a young naval architect, and Kelly, a deck hand—were captured and imprisoned in their own yawl by Kiska Joe, murderous half-breed seal poacher.
Amazing machines seen at Popular Science Institute of Standards that guard you in buying tools and radio equipment
ALDEN P. ARMAGNAC
TWO thousand men pull ing on a hammer handle! Corrugated with massive gears, a huge wheel turns slowly, almost imperceptibly, but with inexorable force! A mechanical hand two thousand times stronger than mine—pulling on the handle of a hammer the claws of which clutch the head of a heavy wire nail.
COMBINING under one roof a town’s entire shopping, business and theater district, a novel “community building” is proposed by Joseph Falk, of New Brunswick, N. J. Under the plan, a town could transplant its “Main Street” to the inside of this structure and build an attractive residential section around it.
MORE like a skyscraper in appearance than a gate, this mighty structure is one of the leaves of the lock gate that soon will close the river entrance to Liverpool’s new dry dock. When completed, the dock of the great English port will be one of the finest in the world, and this lock gate the largest in existence.
RUSSIA will have the largest hydroelectric plant in Europe if plans recently announced are realized. Built on the banks of the Dnieper River, the plant will have a capacity of 630,000 horsepower, surpassed in this country only by Niagara.
APLOT of ground in France—at least in Paris—costs more than an old pontoon boat and the same area of water —so a Paris workman built this neat two-room bungalow, pictured at the right, for his small family on an old boat abandoned along the Seine River.
WITHIN the giant, hollowed-out trunk of a Douglas fir, mounted on a motor truck, Mr. and Mrs. E. A. Wade and their son, of California, are touring the country. Their novel temporary home is a modern two-room apartment that contains all the comforts of home—built-in breakfast nook, cupboard, wardrobe, even electric light and an oil stove for cooking.
AFTER a difficult refining process, Drs. Walter and Ida Noddack of Berlin, Germany, discoverers of the new chemical element rhenium, have succeeded in obtaining and testing two milligrams — seven one-hundred-thousandths of an ounce—of the precious substance.
SEEKING to discover the mysterious forces that hurl molten lava from the crater of Mauna Loa, in the Hawaiian Islands, scientists now propose to weigh the entire mountain! It is impossible, of course, to devise scales to weigh a mountain peak which reaches down some three miles under the sea.
THIS odd locomotive starts with a crank. Once a flivver but now, with flanged wheels, a one-car train, it runs on the regular tracks of the Tabor and Northern Railroad between Malvern and Tabor, Iowa. Only rarely, when traffic is unusually heavy, is it replaced by a steam train.
THE moon exerts a direct influence on earthquakes, points out Prof. H. F. Reid of Johns Hopkins University, as a result of recent investigations. Just as it pulls on the sea to form the tides, the moon strains on the earth. Should a “fault" or slipping of rock be about to occur for any reason, in a given direction, the moon in one position would hasten it; in another, it would delay it.
SOON it may no longer be necessary to stay at home in order to receive telephone messages. A new Swedish invention answers the phone, takes the message, and repeats it to you when you return! The apparatus has been under test for several months and is now reported to have passed all tests.
COMMON clay now is to yield aluminum, in Germany, by a new process made commercially practicable by the phenomenal increase in the use of aluminum throughout the world. In the process the aluminum compounds are dissolved from the clay by means of powerful acids—a process made economically remunerative since the discovery that silica, a by-product of the new process, is valuable in many industries as a catalyst in the form obtained when aluminum is isolated.
THERE is more to a great ocean liner than generally meets the eye—witness this unusual photo of the Leviathan, taken recently at South Boston, Mass, Put in dry dock for a fresh coat of paint, the ocean monster lies with the whole of its enormous hulk exposed.
CHEMICALLY treated pine needles are being made to yield a useful substitute for wool in Germany. In the process the resin is chemically removed from the needles, leaving a “pine wool” of fine strong fibers resembling hemp. This wool is woven into heavy fabrics.
LIKE dragon flies on a floating piece of driftwood, twenty-five planes perched on the upper deck of the aircraft carrier Langley, pictured at the left, as it cruised along the California coast to take part in the fleet's recent battle maneuvers.
GENERATING such terrific heat, when lighted, that a special glass had to be developed, huge 10,000-watt incandescent lamps are being made by the Westinghouse Company to light airplane landing fields at night. A single bulb, inclosedin a device similar to a lighthouse lens, is said to be sufficient to illuminate an airport runway 2,000 feet long.
A STANDARD size Pullman car so frictionless that two men can pull it along the level rails, is the marvel made possible by new roller bearings for car wheels, replacing the present friction bearings. After a try-out on the Chicago, Milwaukee and St. Paul Railway, the bearings are being placed on more than a hundred cars—the first time that complete sets of passenger trains have been equipped with roller bearings.
IONG-RANGE smoking is possible with the novelty cigarette holder below. Twenty inches long when extended, it telescopes to four inches to slip into a pocket. There's no danger of getting fumes in the eyes, either.
TWENTY million telephone receivers and transmitters now in use in the United States are gradually to be replaced by a new type of telephone, pictured above, combining receiver and mouthpiece in one. Patterned after the European-type phone, the instrument is the product of experiments by the Bell Telephone Company, and is said to be an improvement on the Continental type.
PICTURED above is the entrance to one of thirty-nine tunnels that the city of Los Angeles, Calif., has built at its most dangerous street crossings, to make it possible for persons on foot to cross the street in safety. Children on their way to school, in particular, are protected from the growing streams of motor vehicles that make the crossings perilous; and where these tunnels are built, the “stop crossings” usually provided for school children are eliminated.
BABY brother of the giant motors that drive great planes, this remarkable motor—and it actually runs—would fit in a capacious overcoat pocket. A two-cycle engine, it develops a quarter to half a horsepower to drive a small-scale propeller that air-cools it.
FUTURE urban buildings must be taller and thinner and occupy, relatively, less space as compared with streets, in the opinion of a New York architect, Raymond Hood. He would solve traffic problems of great cities by allowing six times as much space on the ground to streets as to buildings.
SAFETY in driving an auto at night depends largely on your headlights, when you get away from the brilliantly illuminated city streets. If your headlights should go out at a critical moment, perhaps going around a sharp turn, almost anything in the way of a serious accident might happen.
PERHAPS astrologers of old were not completely wrong in their belief that the course of human life depended on the stars. Prof. A. L. Tchijevsky of the Moscow Astronomical Observatory recently predicted “great human activity of the highest importance which may change the political chart of the world,” as a result of the expected three-year period of intense sun spot activity that commenced this year.
WILLIE MACFARLANE, former U. S. open golf champion, ran up against a brand-new set of hazards when he recently tried out the psychological tests at Columbia University. One series of tests ranged from estimating the length of two bars to picking out circles and triangles from a printed jumble.
OUT of a single piece of wood, Fred Heiser, of Patteville, Wis., carved each of the intricate pieces spread on the table before him. Chains, pulley blocks and linked figures are among them, all of them designed by himself.
WHEN Montreal's chief of police wishes to speak to a policeman or detective anywhere in the city, all he has to do is give a word to his desk operator. A moment later flashing lights on top of all the poles of the policeman's beat summon him to a phone, or give him orders through a unique numbered code.
BACK from the wilds of Dutch New Guinea, Prof. Matthew W. Sterling, of Berkeley, Calif., leader of the Smithsonian Pygmy expedition, recently returned to report the discovery of a new race of pygmies. Strange ornaments and implements of the tribe, a few of which are shown above, were brought back.
WITH no other tool than a knife, Moise Potvin, expert violin maker, carved out of wood this remarkable detailed picture of a scene in his workshop. Like the familiar Swiss wood pictures, carved and framed in much the same fashion, the charm of this work lies largely in its faithful reproduction of such homely detail as an umbrella, coat and hat, and pictures on the wall.
YOUNGEST licensed radio broadcaster in the United States, Robert Marx, of New York City, converses with Europe every evening from his station 2AZK. Only twelve years old, he reads code signals at amazing speed. His wave length is forty meters, and his call letter is familiar all over the world.
TWO hundred medical students at the University of Pennsylvania had the startling experience the other day of hearing patients’ heartbeats, at a distance of ten feet, come to them like the booming of distant cannon. The sound was made audible by a wonderful new electric stethoscope capable of magnifying heart noises 500,000,000,000 times!
A NEW steel, said to be eight times harder than any of American manufacture, has been developed by the Fried Krupp works of Essen, Germany. Demonstrated recently in this country, it wore smooth the edges of steel files used in unsuccessful attempts to nick it.
TEST yourself with the twelve questions below, selected from hundreds sent in by our readers. For the correct answers, turn to page 144. 1. What famous harbor occupies the crater of an extinct volcano? 2. What famous trees live only on one small peninsula?
VAST workshops that once forged guns and shells to destroy human life have now turned to peacetime products, at the giant Krupp works, in Essen, Germany. The illustration at the right shows a corner of this famous war factory as it is today, with agricultural implements lined up awaiting shipment.
HARMONIES of The color pianist color to accompany orchestral music ment, including are created by a remarkable “color piano" perfected by Leo Geasland, of Los Angeles, Calif. With one hand working the ten keys of his instrument’s keyboard, he creates flashing changes of purple, red and orange from 6,000 concealed electric bulbs.
THE Zeppelin factory in Germany has started construction of the aluminum frame of a huge airship designed for weekly trans-Atlantic passenger service between Spain and South America. This giant liner will carry 100 passengers, crew, luggage and mails.
RUN by radio, a novel electric motor described by Dr. Alexander Meissner, German radio engineer, has as its rotating part a small plate cut from a quartz crystal. Placed in a radio circuit, the crystal vibrates and sets up air currents that cause it to spin.
WOODEN wharves, ships and houses are now being protected against shipworms by a special paraffin treatment developed by Dr. Paul Bartsch, marine biologist of the U. S. National Museum. The process consists of impregnating the wood with paraffin and two kinds of poisons, one to destroy all attacking animal life, the other, parasitic plants.
AERIAL cameras and sound depth . finders are being used in a new survey of wide areas of seas off Central American and Cuban coasts, conducted by the Hydrographic Office of the U. S. Navy. Ships endangered by old and inaccurate charts of the ocean bottom—some dating back to the sixteenth century—will be provided with up-to-date, reliable data as a result of this expedition.
BEES haven't any common sense at all, says a French scientist, J. G. Millet. Instead of deserving credit for their industry and wisdom, he says, they don't even know a good honey-producing flower from a bad one. Experiments have convinced him that a bee is attracted to a flower solely by its odor—it will fly as quickly to a perfumed artificial flower as to a real one.
ANNOUNCEMENT comes from Dr. Ludwig Haberlandt of the University of Innsbruck, Austria, of the discovery of a “heart hormone,” a powerful chemical compound secreted within the living heart and spurring it to action. This compound is to be classed with the secretions of the ductless glands, such as the thyroid.
FINGER-PRINT identification has again been vindicated. When Prof. William Crowther of University College, England, recently asserted that George and Edward Ellis, twin brothers, had finger prints exactly alike, police authorities the world over, alarmed, appealed for information.
FOR the first time in a number of years a comet will be visible in the night sky a few weeks from now. The Pons-Winnecke comet, which visits us every six years, has again returned, and already astronomers are watching it through telescopes, measuring its brightness, and using the spectroscope to find what it is made of.
THE fact that we live longer than did our grandfathers is bringing us billions of dollars in cash, says a great insurance company whose experts estimate that the total increase in earning power of American men and women in the present generation, or since 1901, is $3,500,000,000.
UNDER the direction of the American Society of Heating and Ventilating Engineers, women students from the University of Pittsburgh are being weighed and observed in novel tests to find out how a cooling system for a theater should be designed.
GREATER than Muscle Shoals and second only to Niagara's huge generators, this monster power project on the Susquehanna River in Maryland will soon be completed. Seven great water turbine generators will dispatch electricity over a 220,000-volt transmission line to Philadelphia, sixty miles away.
CURIOUS fins attached to the hull of a vessel near its screw propeller are used in a new English invention to increase the boat’s speed and lower fuel consumption. With the ordinary form of ship, water flows in an upward direction to the propeller.
THOMAS A. EDISON, world-famous inventor, sees the great cotton plantations of the South transformed into producers of rubber. With Henry Ford, he has established an experimental rubber plantation at Fort Myers, Fla., where he is conducting remarkable tests with rubber that grows from a “vine” and with special machinery, including a new combination reaper-press.
TRAINS on the Paris-Lyon-Mediterranean Railroad get their daily bath in what is perhaps the oddest washing machine yet developed—a huge tunnel-like structure that does the work of two hundred men. Known as a “train polisher,” it is a tunnel about the length of a passenger coach, lined with revolving brushes and powerful jets of water.
NEW scientific methods are being used to measure the heat of Kilauea, giant volcano of Hawaii. Under the direction of Dr. T. A. Jaggar, director of the Hawaii Volcano Observatory, borings ten feet deep dot the solid rock at the crater at intervals of a thousand feet.
HOW a naval seaplane takes off from a modern warship's deck, catapulted from a revolving platform, is graphically shown in the accompanying sketches. This latest catapult, now in use on England's battleships, hurls a plane from a moving platform set in motion by compressed air cylinders.
TWO French chemists, Prudhomme and Houdry, announce that they have made gasoline from lignite in commercial quantities. Their process of distillation, now a closely guarded secret, is eventually expected to yield a quarter of a billion gallons of gasoline a year—half the gasoline consumption of France —from twenty million tons of lignite.
half the gasoline consumption of France —from twenty million tons of lignite. Coarser oil is a by-product. Enough lignite, sometimes called brown coal, exists in France, experts estimate, to supply that country with oil and fuel for at least a century and a half.
CRIMINALS who alter documents with any ink that contains iron can be detected by ultra-violet rays, according to Professor Brüning, Berlin scientist. Postal thieves who open letters and reseal them also are branded guilty by the rays; one kind of mucilage, for instance, glows with a fluorescent light under them, while another does not.
CARRYING 110 passengers, this mammoth seaplane, just completed at Friedrichshafen, Germany, sped over Lake Constance on its trial flight at more than 120 miles an hour. A feature of its construction is the tandem four-bladed propellers, one in front of the single main plane and another just ahead of the rudders.
OWING to its large deposits of magnetized iron ore, Magnet Cove, about eleven miles from Hot Springs, Arkansas, brings in radio waves with exceptional results. Tests made with small machines set upon the large boulders of magnetized rock showed that stations were clearly heard at this point that would be received most feebly in other equally distant locations.
GIANT redwood trees, California’s forest monarchs, may appear in Virginia, if experiments prove successful. H. M. Sears, supervisor of the national forest at Natural Bridge, Va., is preparing a shipment of California redwood seedlings, to be planted near Natural Bridge.
WHY can some men fly safely, others not? What qualities make a good airplane pilot? The School of Aviation Medicine, San Antonio, Tex., has undertaken to answer these questions. To this end they are aided by a remarkable instrument which tells the speed with which a man reacts to signals in color, light, and sound, and the speed and coordination of his movements.
SOMETIMES candy explodes, and now and then confectioners find whole shelves of chocolate creams that have burst open. The cause, according to scientists of the U. S. Bureau of Chemistry, is yeast in the sugar filling. Ordinary yeast, like that used for making bread, will not grow in sugar; but there is a special yeast that finds the sweet creamy mixture ideal.
A DISABLED seaplane drifting at sea may broadcast an appeal for help with the newest airplane radio, pictured above, designed by the U. S. Navy for just such an emergency. Small and compact, it is operated by a hand generator, and so works even when the plane’s motors are dead.
BRIGHTLY colored when the sun shines, the feathers of an African bird recently studied by Dr. I. Krumbiegel, German biochemist, become a sad spectacle when wet by the rain. The brilliant dye of its red feathers fades to a pale pink, the leak being caused by the ammonia in rain water.
PORTABLE traffic semaphores are helping solve the traffic congestion problem in Paris. At specified hours of the day they are moved to street intersections where congestion is heaviest—during the business rush hours, for example—then at night they are carried to the theater districts, and on Sundays and holidays to crowded intersections near the railway stations.
AIDED by a sharp chisel, Dr. H. Lutz, of the University of California, has just finished reading the oldest book known to man. The task has taken him twenty years. The chisel was necessary because the “book” is a series of clay tablets, about the size of a pocket notebook, each incased in a baked clay sheath, which had to be chipped away by the sharp tool.
IN OUR March issue we offered $100 in cash prizes to readers submitting the best original designs on the subject of “sports” made from the fourteen pieces of the Stomachion puzzle game of Archimedes. A number of the prize winning entries are reproduced here.
Your set or your location may be to blame—What to do for best results
IT'S all very well for people who live in big cities to claim that radio fans no longer want to listen to distant stations, but the fact remains that a large percentage of radio listeners in this country must either bring in faraway stations in a satisfactory manner or else go without radio entertainment altogether.
How to Get C-Current from B-Eliminator, Cut Out “Motorboating,' Decide Correct Antenna Length, and Other Hints
THE popularity of the B-battery eliminator, coupled with the growing use of one of the power type tubes in the last audio amplifying stage of the radio set, has brought up the question of what to do about the C-battery. Power tubes require from nine to forty volts of C-battery.
IN WIRING a radio set you are sure to run into places where it is almost impossible to get the soldering iron in contact with the wires you want to solder without pressing the hot body of the iron against the spaghetti tubing or other insulation on adjacent wires.
DIFFICULTY often is experienced in operating a set equipped with a resistance coupled type of audio amplifier by means of a standard B-battery eliminator. Either the quality is poor or there is that peculiar “put-put-put” effect nicknamed “motorboating.”
MANY types of commercial receivers are now made with special arrangements for illuminating the dials. Special dials with lights built in are available to the home constructor of radio sets. In addition, there are several styles of panel lights that can be applied to sets already constructed to obtain the same effect.
DURING the days when bare bus wire was most popular for wiring radio sets, any type of pliers was satisfactory. The fashion now is to use insulated wire. Consequently time must be spent scraping the insulation from the end of the wire at each joint or connection.
SOMETIMES a worth while improvement in tone quality can be obtained by connecting a fixed condenser across the loudspeaker terminals as shown in Fig. 6. Capacity at this point in the radio circuit tends to reduce the strength of the audible tones at the upper end of the scale.
THE question as to whether anything can be done about eliminating scratching and hissing noises produced by local electrical machinery depends upon the nature and location of the machinery causing the disturbance. The general impression is that reducing the length of the antenna or using a loop will improve matters, but this is not true in all instances.
ANOTHER use for small fixed condensers is to increase the selectivity if you find difficulty in separating stations on adjacent wave lengths. The simplest way to connect a condenser at this point is shown in Fig. 8, and this illustration as well as the one in Fig. 6 shows the correct way to hold a small fixed condenser while soldering a wire to one of the lugs.
Where neighbors are close and space is limited, try this outfit
JOHN E. LODGE
“IF SOMEBODY doesn't murder that bird pretty quick, I’m going to do it myself!” shouted the irate occupant of the third floor back. The rest of the boarders unanimously agreed that violence was called for—the sooner, the better. Meanwhile the cause of the impromptu indignation meeting was lolling back in his armchair enjoying the hideous wails and thumpings of a fourth-rate jazz orchestra rumbling forth from an antiquated tin horn type loudspeaker.
“A hundred and fifty when joined to a tree Makes afine garment to warm you or me." That couplet fits the picture above and poses a riddle. What cozy-sounding garment is suggested by the sketch? Rebuses and riddles are a test of your wit and imagination.
Facts and Figures about Materials and Labor That Will Help When You Plan to Construct Your House
JOHN R. McMAHON
MY TAILOR is building a house. The other day he asked what I would think of him if, when I asked when a suit would be ready and what it would cost, he replied: “Maybe in a few weeks, maybe some time next fall. I never promise any time. Don't know the cost exactly, fifty or seventy-five dollars, perhaps.
Air Moistener, Battery Handle, and Other Ingenious Kinks
UNLESS you are equipped with a special jack designed low enough so that it can be placed under the axle when a balloon tire goes flat, you may find it extremely difficult to change tires. If you get stuck this way, your spare tire may solve the problem.
WHILE the best possible insurance against spring breakage is a set of properly adjusted recoil snubbers, you will find that fabric belts clamped around the axle and the frame as shown in Fig. 2 are worth while. The belts will not interfere with the free action of the spring when a bump is encountered, but when the car starts to bounce too high, they will prevent bending the springs the wrong way so far that they break.
THE short piece of hose that you keep in the garage to wash the car can be kept in good condition, handy and yet out of the way, by bolting an old rim to the wall near the water tap as shown in Fig. 3. Almost any old rim will provide ample space for the short piece of hose that is ordinarily used in the home garage.
FIGURE I shows you how to make a simple handle that will fit almost any storage battery. It is made from a stout piece of wood, such as an old shovel handle or fork handle, and the end links are from an old cross chain. After the holes are drilled at each end, two links are straightened out and passed through the holes.
IF YOUR car is fitted with rims on which the lugs are part of the rim, a good sized turnbuckle can be used to compress the rim and allow you to take off a tire even if it is badly rusted. While it is better to use a large turnbuckle, a small one will do if you piece out from the turnbuckle eyes to the lugs by means of hooks of the proper length.
IF YOU find it necessary to fit new, stiff rings and you have no ring compressor, a string arranged as shown in Fig. 6 will permit you to do the job without trouble. Tie the end of the string to any convenient bolt, pass it around the ring and pull on the handle.
ONE of the objections to the ordinary way of building a moistener for the air that goes into the manifold of your motor is that there is a chance, when the car goes over a bump, of the water’s splashing up and being drawn into the manifold in the liquid state.
Under-Inflation and Neglect Cost You Miles and Dollars
What Was Wrong with Markin’s Car?
"OLD BURR sure has a permanent cramp in his pocketbook,” grinned Joe Clark to his partner, Gus Wilson, as their departing customer let in the clutch and drove away from the Model Garage. “He’s penny-wise and pound-foolish,” observed Gus. “Our prices on tires are reasonable and we don't palm off stale stock.
Semiportable Summer House Offers Many Comforts—Has Substantial Floor and Frame
HENRY S. LARABY
CAMPERS who have picked a pleasant location to which they return year after year—and their number becomes larger each season—will find many advantages in constructing a semiportable canvas house of the type illustrated above. The sides, top and ends can be transported easily by car.
How to Make a Neat and Convenient Stand for Small Machine Tools—Reduces Noise and Vibration
COLIN L. BLAIR
WHEN the writer purchased a small screw cutting bench lathe, he was confronted with the problem of constructing a satisfactory table arranged for its motor drive. The usual method of driving small lathes seems to involve the use of an overhead countershaft, and this was not desired.
WHEN fiber wallboard is to be covered with wall paper or with the easily applied plastic paints that are now so popular, the average home worker is puzzled as to the best way to make sure the joints will not crack open in the course of time and disfigure the walls.
IN TURNING a wooden article which is composed of two or more segments, it is difficult, if not impossible, to turn the piece first and afterward split it up. That is especially true if an odd number of segments are required and the object must still retain a perfect circular cross section.
For all members of the family—A novel, fascinating pastime
ARTHUR L. SMITH
PUZZLES of the flat moving block type, which are now so popular, are always of absorbing interest until solved. The one here illustrated should retain its interest longer than the ordinary puzzles because it assumes the form of a fascinating game.
TRULY can it be said that a fishing rod is as good as the care you have given it. Even a cheap machine-made bamboo rod, if kept in good repair, will be equal eventually to a high priced rod that has been neglected. A rod may be in a good, indifferent or bad condition when you go about repairing it.
Yet Old Bill Had to Turn the Mill Shaft Quickly—How He Did It May Help Y ou Solve Similar Problems
OLD BILL went to meet the office man, who was hurrying through the shop toward him. “What now?” he asked. “The Binklers want you to come out to their saw mill as soon as you can. The shaft on the band mill is scored badly because it ran hot, and they can't get the wheel off so they can send the shaft to the shop.”
How to Replace an Old Electric Light Bracket with a Sconce
GEORGE A. WILLOUGHBY
ARTISTIC electric wall sconces can easily be installed in place of old-fashioned brackets which have become defective, shabby or otherwise unsuitable. The first step before starting this or any other type of repair or replacement work is to open the main house switch.
FOR the home shop not fitted with a power driven saw, the hand operated circular saw illustrated will be found most handy. The whole cost of the one shown was $3.86, which included the grinder and two circular saws, one for ripping and the other for crosscutting.
Shellac and Wax—Clear and Dark Varnishes—Brushing Lacquer
RALPH G. WARING
HOW home? shall Which I finish is the better, floors shellac of my or varnish? Are brushing lacquers serviceable for floors? These and similar questions are asked endlessly in every paint store. Let us, therefore, review the various finishes.
THIS month’s “comicull" is a rubber band tractor, which will please the children because it will run. The materials needed are a cardboard box in. or less in diameter, a large rubber band, a stiff wire, two disks of soap or paraffin, and a small spool or other round object for the rear roller.
AFTER building a Spanish galleon from plans published in POPULAR SCIENCE MONTHLY, Floyd E. Freeman of Philadelphia designed the stand illustrated, which differs considerably from those ordinarily used for decorative models. It has the advantage that it does not interrupt the flowing, graceful lines of the hull.
TO CLAMP the tailstock and tool rest on a wood-turning lathe of the type illustrated, the workman ordinarily must reach underneath the lathe. Adjustments may be made more conveniently if the clamping device is rearranged so that the handle is above the lathe bed.
How to Prepare the Surfaces—The Undercoats—Straightening Out Rough Spots and Laps
MRS. ANDREWS, who lives across the street from us, was on the phone. “I've got a fine idea!” she announced, with her usual enthusiasm. “Some of the ladies in our card club have been finishing things with the new brushing lacquers. I guess I started them; anyway, it’s quite the popular thing now.
UPON returning from the garage or cellar workshop, one is apt to leave footprints of concrete dust upon waxed or polished floors. Wiping the feet hastily upon a mat at the door will not always remove the white dust. If, however, the mat is impregnated with a teaspoon of light machine oil in a pint of gasoline, the very act of walking over it will be sufficient to dust clean the soles of one’s shoes.
Our Blueprints Will Assure Your Success in Making a Highly Picturesque Model
CAPT. E. ARAIITAGE McCANN
OLAF TRYGGVASON’S “long serpent" had thirty oars a side; one of Canute the Great’s ships had sixty. The Viking ship model we are building is a sextensesse, with sixteen a side, which means that her prototype had sixty-four rowers and a crew of from seventy to eighty.
THIS bathtub submarine, properly balanced, will perform amazing feats. When released on the surface with planes set for submerging, it starts under with a whirr and gurgle, and a stream of bubbles from the air outlet back of the conning tower marks its course.
ANY ONE of the blueprints listed below can be obtained for 25 cents. The blueprints are complete in themselves, but if you wish the corresponding back issue of the magazine, in which the project was described in detail, it can be had for 25 cents additional so long as copies are available. The Editor will be glad to answer any specific questions relative to tools, material, or equipment.
IMITATION amber used in so-called amber rim glasses is a form of celluloid, which often can he repaired satisfactorily by using celluloid cement. One of the easiest repairs to execute is the replacement of a small piece of celluloid on the nose piece of nose glasses (Fig. 1).
THESE plant sticks are excellent projects for those who find pleasure in simple woodwork. They are made with a coping saw, painted in bright enamel colors, and mounted on sticks ⅛ in. scpiare and about 36 in. long, or long enough to bring them in their natural relation to the foliage.
A BASEBALL game for amusing small children can be made as shown below. A baseball diamond is laid out on a piece of wallboard 3 by 4 ft. (or smaller) and holes slightly larger than the marble to be used are bored in the positions indicated. This is glued on a foundation made of wood or wallboard. Then 1½-in. wire brads are driven in where shown, and a spring arranged to “bat” the marble.
YOUR nerves govern your life — your efficiency, your happiness,your health. If your nerves are depleted, you cannot concentrate or think clearly; you have not the “pep” and spirit to enjoy your pleasures and sports; you have not the physical comfort and well-being without which happiness is impossible.
Has Work, Bench, Tool Chest, and Tank for Toy Boats
MOTHER'S problem is to keep the children interested outside the house; father's is to keep the yard looking something more like residence property than a junk yard. And the problems are complicated if one lives in an apartment or bungalow court, where the back yard, if any, is very restricted—especially as boys will be boys, including the neighbors’.
SHELLAC can be purified to such an extent that it makes a perfectly clear solution in alcohol. It then becomes much more valuable to the home worker than the common commercial grades of shellac. It can be used for protecting pictures and other delicately marked or colored surfaces; it also can be used as a finishing varnish on woodwork with the great advantage that it will not turn white in spots, as ordinary shellac is apt to do when affected by moisture.
A REMARKABLE acrobat is this wooden monkey. It can balance on heels or toes in the most grotesque and apparently impossible positions and do all sorts of weird, rhythmic dances. The monkey acrobat hanging by his toes This novel toy, which is a favorite in India, usually is made of teakwood, but it can be whittled from any hard, tough wood.
A TOOL for applying lacquer to flat metal surfaces, which is in some respects superior to the camel's-hair brush usually employed, is nothing more than a paddle shaped piece of cigar box wood, about 1 in. wide at the end, around which a piece of velvet is glued.
WITH a few pieces of lumber left over from building a house, an iron post, two discarded automobile hearings and some canvas, W. E. Robertson of Pelican. La., built the merry-go-round illustrated. A 2-in. iron post 7 ft. long was set in the ground and fixed rigidly upright with concrete.
A GROCERY box, some tan canvas from an old army tent, a piece of leather belting, a discarded cushion, a few brass headed upholstery nails and various odds and ends were converted into the treasure chest footstool illustrated. The box was turned upside down, padded with the cushion and covered with canvas.
WOODEN tanks, pipes, decks, floors, partitions, and silos can he made watertight or practically so if the joints are prepared as indicated in the accompanying diagram. The edges are grooved by compressing, not removing, the wood, as at A, Fig. 1.
WE THINK of the simplest things last. This is perhaps the reason why it never occurred to the writer until recently to make thread templets like that shown in the illustration. Nothing could he simpler or more effective and reliable than to use the cross section of a screw in making a drawing of that screw.
WHILE the larger shops do their keyseating of pulleys or gears on special machines and the lone mechanic in a factory repair shop must cut his with a chisel, there is a stage where neither method is exactly suitable. Small shops frequently do such work on the shaper.
IN ASSEMBLING the type of pipe wrench shown in the illustration, it is difficult to hold the nut in the frame, and at the same time keep the nut guards in place. A trick to make the guards behave is to put a wad of paper between them in the nut. When the jaw enters the nut, the wad of paper is pushed out.
Rubber Band Acts as “Keeper” for Set of Steel Numbers
FRANK W. BENTLEY
SMALL steel punches for stamping numbers on metal are easily lost. To hold them in the usual wooden case, merely stretch a rubber band around the protruding ends, as shown. BEFORE being babbitted, cast iron bearings should be heated to about 450 deg. F.
A MOTOR boat searchlight can he controlled in rainy or cold weather without opening the pilot house window, if it is mounted as shown. The standard is a piece of 1-in. pipe 5 ft. long with a T fitting at the upper end. A 10-in. length of pipe, an elbow, and another piece 8 in.
SOLDERING iron and gluepot are household essentials. To keep them ready for instant service, I make use of the stand illustrated. The pipe that supports the soldering iron or gluepot is screwed tightly into a bole in the center of the wooden base block.
HOLDING small, slender work in a micrometer is a hard thing when the piece is so short and at the same time so thin that there is not room enough for the thumb and forefinger between the anvil and the spindle. If such work has to be measured continually, as when the product of a screw machine has to be cheeked, the task becomes one that is more than merely difficult—it becomes nerve racking.
IN AN industrial plant well away from shops and foundries there was a duplex steam pump to feed the boilers. A piece of pipe fell on it one day and shattered the valve gear bracket so badly that it was even beyond welding. This did not stump the ingenious plant mechanic.
GIB head keys are much easier to remove than those without heads, provided one is able to drive against the head. However, when the key is in a webbed pulley or gear, there is no opportunity to drive them out in the usual manner. To take care of such conditions we made the key puller illustrated.
WHEN there is a long piece of work to be held in a vise, the machinist sometimes piles up boxes, pulleys, or anything at hand to support the end of it. The accompanying illustration shows a support for such work that is always handy when wanted, but never in the way.
SETTING a key-seating cutter above the center of a shaft is tedious when the shaft is some odd diameter, and bothersome if the cutter is covered with oil, so a number of machinists make a practice of guessing at the location and letting it go at that.
TWO simple devices are illustrated that have proved extremely useful in a Denver tin shop. The first is a pair of rivet heater's tongs with wide jaws. These are 4-in. strips of ½ by 1 in. iron ground to an edge from the outer sides and welded on each jaw of the tongs.
INSTEAD of chipping oil grooves in pulleys or bushings, they can be cut by putting a properly shaped tool in a boring tool holder and working the lathe carriage hack and forth by hand while the pulley is stationary.
IN SHARPENING drills, the key to the situation is to keep the point central and of proper width. A drill with a correctly formed, central point is rarely out in any other way, because such a point is difficult to produce except by correct grinding.
BENCHES in many home workshops and in the majority of manual training shops are fitted with wooden vises of either the cabinetmaker’s or carpenter's type. When a board is clamped at one end of a wooden vise, the jaw usually is twisted out of parallel with the bench top.
FOR making blocks and deadeyes for ship models, I have found that redwood is easily worked and does not split readily. Strips cut from an old Tsquare were utilized for this purpose in my own case. The wood is of such a color that no varnish or paint is necessary.
EVERY mechanic takes pride in a shop that is clean and free from rubbish. He likes to have his tools on his workbench while in daily use or in the tool box if needed on but few occasions. While keeping the shop clean, do not forget the shafting above.
CHILDREN enjoy drawing pictures and “playing school,” as they describe it. When they begin to go to school they do cheerfully a surprising amount of home study. It pays well, therefore, to provide a convenient desk for them. The one illustrated is in the form of a combination desk and chair and is designed especially for use in an apartment or small house in which there is little room for a child’s belongings.
A BRILLIANT, colorful “feather mosaic” forms the striking decoration of the serving tray illustrated. It can be duplicated by anyone who has a parrot or is able to obtain a variety of bright hued feathers. In this case the feathers were moulted by a small yellowheaded Mexican bird.
WE MEN—and boys too—who make things for our home generally get less use out of such articles than do the other members of the household. Here’s a project, however, that will please everyone. It is a bathroom medicine cabinet with a special shaving outfit compartment that has a drop-door shelf.
FEW questions that arise in connection with your home workshop or such repair jobs as you do about the house have not been fully answered in past issues of POPULAR SCIENCE MONTHLY. If you had a complete file of the magazine, properly indexed, you would have an encyclopedia of extraordinary completeness.
PRINTED pictures on paper may be transferred to glass for the purpose of making transparencies or even lantern slides. First thoroughly clean the glass and cover it thinly with dammar varnish or Canada balsam thinned with turpentine so that it flows freely.
A WONDERLAND of colored flashing lights, Broadway continues to dazzle New Yorkers and visitors from all over the world with new and constantly changing signs. Magical effects of drifting clouds, leaping flames and surging ocean spray, are the product not only of master electricians and mechanics, but of artists as well.
AVOCADO blossoms, the flowers that precede a crop of alligator pears, change their sex from morning to afternoon. This was the amazing discovery of Dr. A. B. Stout, of the New York Botanical Garden, seeking a reason for barren orchards planted with alligator pears. He found that certain blossoms were male during the morning and female in the after, and others vice versa.
SCIENCE has developed in a sort of ascending spiral, according to Dr. J. Newton Friend, of London, England, lecturing before the Royal Institution. Scientific history repeats itself. For instance, Hero of Alexandria, a Greek physician who lived about 100 B.C., recorded what is generally known as the first steam engine.