EXPLANATORY foreword: To aid getting ahead through investment —that is the object of this department; it does not foster speculation. But something happened in the financial world, beginning October 24, 1929, which affected investors as well as speculators, causing a violent re-adjustment in viewpoint and reasoning as applied to money.
THE Booklets listed below will help every family in laying out a financial plan. They will be sent on request. The House Behind the Bonds reminds the investor of the importance, not only of studying the investment, but of checking up the banker who offers it.
Most of It Is Lost through the Roof and Walls; How Careful Insulation Prevents Waste of Fuel
F. G. PRYOR
MOST people carefully bar their doors to prevent any loss of valuables, and at the same time make no particular effort to stop the heat from leaking out of the house through roof, walls, and windows. Fuel is the largest single item of expenditure in maintaining the comfort of the ordinary home, and yet it has been estimated conservatively that the annual waste in fuel in the United States amounts to $450,000,000 just because of poor or unscientific construction of dwellings.
CAN any one list some adequate reasons for the tremendous increase in the wearing of glasses by persons of all ages during the past thirty years? To believe the oculists you would have to assume that there was no getting away from the terrible onslaught of spectacles which was destined to engulf the whole human race within a decade or so.
“A BOLISH all the speed laws!” With that drastic suggestion, Paul G. Hoffman, Vice President of the Studebaker Corporation of America, exploded a bombshell at a recent meeting of the National Safety Council in Chicago. The members of the Council, gathered to consider methods of promoting safety in various fields, had devoted much time to the urgent problem of automobile speed limits.
Remarkable Gyro-Electric Mechanism Holds the Stick and Guides an Airplane on Its Course for Three Hours without Human Aid
OVER Ohio, the other day, a big tri-motored Ford plowed through the air on its way to Washington, D. C. Four men leaned back at ease in the passenger cabin. Yet the pilot’s compartment was empty. A metal airman, scarcely larger than an automobile battery, was holding the stick.
New Inboard Runabouts, Outboard Cabin Cruisers, and Commuter Hydroplanes Meet the Demands for Sport and Speed on Uncongested Water Highways
ALDEN P. ARMAGNAC
THE “flivver motor boat” is here. For the first time in motor boat history, a fast inboard “runabout”—meaning a small open craft for sport and errands—can be bought for the modest price of an outboard. An entirely new type of high-speed motor, light in weight and portable, that can be installed within the hull of a boat, has made it possible.
IN 1872, Edward Livingston Youmans founded POPULAR SCIENCE MONTHLY. A friend of Spencer, of Huxley, of Tyndall, this blind, self-taught scholar walked with the kings of science and retained his human touch. He spent his life opening a world of wonder to the many who lacked the benefit of technical training.
Here Are the Facts about Present-Day Gasoline Every Car Owner Wants to Know—What It Is, Where It Comes From, and How Science Produces and Improves the Million Barrels Consumed Daily
E. H. HAMILTON
GASOLINE, many people are now discovering, is not just a smelly liquid that must be pumped into the auto tank at periodic intervals. Different gasolines may look alike. They may even smell alike and yet be as different in performance as a tugboat and a Gold Cup racer.
BY SOLVING a mystifying archeological jig saw puzzle, members of the Egyptian expedition of the Metropolitan Museum of Art, New York City, have reconstructed for the first time shattered statues of a feminine pharaoh who ruled Egypt with an iron hand 3,400 years ago.
Art Authority Describes the Latest Theory of “Gestalt ” Comparing It with Freudian and Other Ideas of Behavior
A. T. POFFENBERGER
PSYCHOLOGY is the science of running things. Driving an automobile, piloting an airplane, building a house, writing a book, constructing a machine, winning a war, making a success out of a business; all these are compounded out of human thoughts and actions.
Gigantic Eight-Motor Planes to Carry 160 Passengers and Crew in Roomy, Hollow Wings
JOHN E. LODGE
"FLYING hotels” with accommodations for 160 air passengers are planned for American airways, according to the recent announcement of a Connecticut firm which projects their construction. The monster land planes, whose wing span of 262 feet would make them nearly twice the size of any airplane ever built, would be used for cross-country transportation in competition with railroads.
Ice Yacht Pilots Match Their Skill at 100 Miles an Hour—The Speediest Motorless Sport in the World
IT IS a bleak wintry day on the Shrewsbury River in northeastern New Jersey. A cutting wind sends flurries of snow scudding across the open expanse of black river ice. Hundreds of cars, and people bundled in furs and mackinaws, line the southern shore.
Testing a Transatlantic Mail Rocket—The Latest Advances in Airplane and Dirigible Construction
NOW ready for test, the first model of the transatlantic mail rocket designed by Prof. Herman Oberth, Berlin experimenter, will fly alone. No human being will venture ascent in the thirty-foot projectile that the inventor plans to fire over the North Sea in a test of its propelling fuel.
A STRUCTURAL girder so light that a sixteen-foot length can be lifted by the little finger, yet so strong that it will support sixteen men, is one of the latest achievements of the United States Bureau of Standards. It is made of trussed aluminum strips, and is being used for airship building.
SUNNY days like those of midsummer, or nights with full moon and starlit skies, are reproduced at will in a unique “weather room” constructed by a Pittsburgh, Pa., glass company to test the advantages of different colors for increasing the visibility of airplanes.
TWO minute and two hour hands are features of a new style of clock developed especially for use in airplanes. Two stationary hands are colored red and are set by the pilot at the start of a flight by means of a knurled knob to show the time of the take-off.
SIX “blimps” operated by an Akron, Ohio, rubber concern and forming America’s only commercial dirigible fleet are reported to have carried 6,000 passengers more than 132,000 miles without injury to passengers or crew. The tiny dirigibles have landed more than 4,000 times in establishing this record.
NO MATTER how queer the inventions of aviation enthusiasts, a number of manufacturers take pains to consider them carefully for fear that otherwise some really revolutionary idea may be lost. A Detroit aircraft firm even maintains a special research bureau to consider the worth of what are generally regarded as “nut” inventions.
ONLY about five percent of air passengers are subject to “airsickness,” that curious aerial malady that corresponds to seasickness on the ocean. This is revealed by a survey recently made by the Daniel Guggenheim Fund for the Promotion of Aeronautics, which also concludes that airsickness is much more easily prevented and cured than seasickness.
DRIVEN by a 600-horsepower motor, and with the framework of its streamlined fuselage constructed of a new lightweight type of steel, the P-6, latest Army pursuit plane, is said to be capable of a speed of 181 miles an hour. Officials say that it will enable the United States Army Air Corps to bid successfully against the air services of the world for supremacy in pursuit aircraft.
PATAGONIA, the sparsely inhabited southern region of Argentina and long the symbol of remoteness, is now linked to the rest of the world by air mail. Twice-a-week mail and passenger service has just been inaugurated between the city of Commodor Rivadavia, situated less than 600 miles north of Cape Horn, and Buenos Aires, in Argentina.
DESIGNED for transatlantic flying, a new amphibian built at Chicago is said to be able to fly 4,200 miles without alighting. It is the largest of its kind in the world. The all-metal liner has a wing spread of seventy-two feet and carries fourteen persons.
ABOUT 5,845,000 pounds of express have been carried by airplanes operating over American air lines during the last three years, according to a recent report of the United States Department of Commerce. Fast delivery of newspapers is one of the services performed by express planes, and another has been the transfer of large sums of money in bullion and currency.
BUSINESS letters by air mail would receive special attention, plane operators have contended, if the recipient of such a letter knew that it came by air. However, the envelope, the only evidence of its manner of delivery, often is removed and thrown into the wastebasket before a letter reaches the person to whom it is addressed.
FOUR planes still remained in the Daniel Guggenheim Safe Aircraft Competition at this writing, with a fifth a possible contestant. The rest of twenty-five planes originally entered either had failed to pass the qualification tests or had withdrawn.
IN A successful maiden flight of half an hour, the world’s largest land plane— the Junkers monoplane G-38, with a wing span of 148 feet—recently vindicated the expectations of its builders. It is called the nearest approach to the ideal of airplane designers—a “flying wing,” unimpeded by outer projections and with exposed motor surface and fuselage reduced to a minimum.
ONE of the most serious problems with which Commander Richard E. Byrd had to contend on his recent spectacular dash by air to the South Pole was how to find his way back, air experts declare. Capt. L. A. Yancey, air navigation authority, points out that at the pole all directions are north.
THROUGH a recently developed system of transporting cut flowers by airplane, thousands of tons of blooms from the Netherlands, put aboard fast planes at the Dutch airports of Schiphol and Waalhaven, reach foreign markets each day still fresh and dewy.
TWENTY-TWO New Jersey civilians recently formed the “Newark Air Service,” an independent flying organization, and started taking flying lessons. Then they donned uniforms of their own creation, appointed officers, and offered their services to the Government as a unit of flying “Minute Men” in the event of a national emergency.
NEW economy in producing helium gas for dirigibles is reported by the United States Bureau of Mines. The cost has now been reduced at its Amarillo, Texas, plant to less than a cent and a half per cubic foot. Once helium cost $2,000 a cubic foot.
Which Five Inventions Are Greatest? Seven Cash Prizes for Best Selections
A SPIRITED discussion was started among the editors of POPULAR SCIENCE MONTHLY the other day by the news that a Philadelphia judge had admitted the talkie confession of a burglar in evidence at the trial of the prisoner. “Here,” said Edgar C. Wheeler, Associate Editor, “is a striking example of the quick and far-reaching effects of an ingenious invention.
1 Which, in your opinion, are the five inventions that have exercised the greatest and most far-reaching influence on the progress of civilization? For the best answers to this question, giving the names of the inventors and the reasons for your selection, POPULAR SCIENCE MONTHLY will award $100 in cash prizes—a First Prize of $50, a Second Prize of $25, and Five Prizes of $5 each.
THE successive operations by which a typical modern grain elevator receives, stores, and handles grain for shipment are pictured here and indicated by number. The pneumatic equipment at the left in the drawing is a recent device for reconditioning wet grain.
How Science Conquered the Mold Which Menaced Valuable Murals of the Great Panama Waterway
GEORGE LEE DOWD
A FEW months ago the five mural paintings depicting the construction of the Panama Canal, canta vases covering 400 square feet of wall space in the Administration Building at Balboa, were in danger of extinction from the ravages of mold.
The War Bird-Instructor Who Taught Larry Brent Tells of Tight Adventures with the Unexpected
THE unexpected rides with every pilot. From the take-off run to the three-point landing anything may happen. My strangest flying adventure took place only thirty feet above the ground. I had landed a Travel Air at a practice plot five miles from Curtiss Field, New York.
RINGS of crystal quartz not much larger than finger rings form the hearts of the most accurate portable timekeepers yet devised. Developed by Dr. W. A. Marrison, of the Bell Telephone Laboratories, New York City, the new device has operated as a precision clock, week in week out, with a daily error of less than one one-hundredth of a second.
IN SEARCHING for a poison, two University of Toronto, Canada, biologists, G. W. H. Lucas and F. C. Henderson, recently discovered a new general anesthetic, cyclopropane. Tested upon animals, this gas is said to have proved superior to chloroform for certain kinds of surgical work.
AT THE Presidio in San Francisco recently United States military authorities tried out an Army truck running on a new fuel system burning wood. The combustion outfit somewhat resembles a furnace. Wood blocks are burned in an open container, the fumes given off pass through four cylinders, and emerge as gases which, carried to the engine, are there exploded like ordinary gasoline.
NATURE’S freaks usually are the least expected. Roaming his orchard a few weeks ago, Cook Walker, of Laytonsville, Md., singled out a York Imperial apple tree thirty-five years old ready to cut for fireplace wood. He felled it and laid it on the block.
A MONSTER electric shovel, which can lift 100 tons—the weight of a medium-sized locomotive—to the height of a seven-story building, began a Herculean job recently when the Fidelity coal mine, Du Quoin, Ill., was opened. Largest in the world, the excavator was designed for a capacity of twenty cubic yards.
HEARING with an eardrum vibrated by electricity instead of by sound waves, a man in New York City recently listened to music inaudible to other members of an audience witnessing a demonstration by Dr. Sergius P. Grace, of the Bell Telephone Laboratories.
FOR the first time, the beauty of field and garden has been put on a quantitative, scientific basis. Actually charting the colors of cosmos, rose, and gladiola is the feat recently accomplished by Dr. Samuel G. Hibben, of the Westinghouse Lamp Company.
TEST your knowledge with these questions, chosen from hundreds asked by our readers. You will find the correct answers on page 150. 1. How do you keep your balance? 2. What makes you sneeze? 3. What makes muscles work? 4. Why do some people grow so tall?
A TIME and energy saver of unusual efficiency has been introduced into railroad yards of London, England. A scene which is becoming familiar at King’s Cross Station is the coaling of a giant locomotive within fifteen minutes, by an electric elevator.
ROCK crystals as long as an automobile were recently uncovered in a quarry near Albany, Maine. The remarkable columnlike structures of beryl measured from twelve to fourteen feet long and from two to three feet thick. A movement is on foot to obtain the gigantic semiprecious stones for preservation in a museum.
A REVOLUTION in the paper making industry may result from experiments conducted by the United States Bureau of Standards to show that certain wood fibers can be chemically treated to remove the excessive amounts of impurities they contain and thus make them suitable for the manufacture of the high-grade, durable papers used for permanent records.
UNTIL a few weeks ago the world’s biological chemists had let two vitamins escape unnoticed. News has come from London, however, that Katherine Hope Coward and her colleagues at the Laboratory of the London Pharmaceutical Society have captured one of these chemical eels, and that Vera Reader of the Biochemical Department at Oxford University has captured the other.
AN OCEAN liner many times as powerful as the Leviathan could be dragged backward through the water, in spite of churning propellers, if it were attached to a giant pulling apparatus for testing metals recently installed in a laboratory at Berlin, Germany.
THIS aerial photograph of the mammoth Goodyear-Zeppelin hangar under construction at Akron, O., was taken during the recent ceremonies marking the beginning of work on the United States Navy dirigible ZRS-4 Built to accommodate what will be the world’s largest lighter-than-air craft, the hangar is capacious enough for three football games to be played simultaneously within it.
PLANS for a $10,500,000 air terminal building for Los Angeles, Calif., which will include a roof-top landing field nearly 1,000 feet long, have been embodied in a realistic model of the building prepared under the direction of O. R. Angelillo, chief engineer in charge of the project.
A LABOR-SAVING machine that saved no labor for its inventor was completed recently by Thomas G. Duncan, of Los Angeles, Calif., after six years of work. Duncan’s apparatus is an electrical working model of machinery designed for use in mining operations.
IN EXPERIMENTS to determine the nature of pain, Prof. Uginelli, of Florence, Italy, has found that the cheek and the forehead are by far the most sensitive skin territories of the body, while the outer arm is by far the toughest. This toughness can be explained by centuries of wear and tear to which the arms have been subjected in maintaining the body defenses.
RAYS emitted by growing onion roots stimulated the growth of cells from a frog’s eye in a recent laboratory experiment conducted by a Swiss biologist, Dr. Andre Naville. His test confirmed the earlier discovery of the mysterious “onion rays” by a Russian biologist, Dr. A. Gurvitch.
A BIOLOGIST once computed that if oysters were allowed to reproduce without check, they would swamp the whole earth inside of eight years. Now Charles Elton, zoologist of Oxford University, England, has stated that if the mouse population did not suffer a periodic decrease, the situation for mice would be similar to that for oysters.
THE alleged Chinese custom of shaking hands with one’s self instead of with the other fellow may spread over the world if sanitary experts have their way. Bacteriologists and physicians often insist that disease germs may be communicated from one person to others by a handshake.
WHALE and walrus meat, centuries old and buried in glaciers, has often been found in such an excellent state of preservation that it would make palatable roast steak for dinner. A new type of fishing trawler, however, that will do the work of the glacier for ordinary fish within four seconds, recently made its trial trip at Kiel, Germany, and is expected to revolutionize deep-sea fishing methods.
FISHERMEN need no longer fear that droughts will cut off their supply of bait, in view of a great angleworm farm which is now in the process of rapid growth at Alhambra, Calif. With a crop which for only six months reached the figure of 300,000 worms, this novel industry may challenge the raising of citrus fruits in that state for a place on the map.
PASTRIES that tempt by their appearance but prove to be filled only with sawdust, and well-browned turkeys whose wax flesh defies the strongest teeth, are among the products that come from the strange kitchen of Herbert Bohrmann, of New York City.
CARRYING a roll of paper in its barrel, a novel pencil from Germany, though no larger than an ordinary magazine pencil, will supply at a moment’s notice all the materials essential for writing a note. In addition, it carries extra leads, the lead and the paper being separately operated.
THIRTY-THREE giant excavators, some of them digging 8,000 tons of clay in twenty-four hours—more than 1,400 men could dig in the same time, working in ten-hour. shifts—are part of the elaborate machinery required to imprison the unruly and malodorous River des Peres, near St. Louis, Mo., in a man-made tunnel and force it to change its course.
TOSSING its driver into the water and then charging straight for the river bank, an outboard motor boat came to rest high and dry during a recent race at Rickmansworth, Hertfordshire, England. As the Invicta II sped around one of the buoys marking the course in the River Colne, a tributary of the Thames, H. G. Reigate, who was at the wheel, was jerked cleanly out of his seat and left behind.
A MORE lustrous and valuable mother of pearl from clamshells for use in the manufacture of buttons is the aim of Professor Max Ellis, a Missouri physiologist and investigator for the United States Bureau of Fisheries. Rejecting Nature’s methods as too perilous for the early life of clams, he will raise the young ones in test tubes that can each contain millions of the little buttons-tobe.
LEG crossing, once a unique privilege of man but lately taken over by women, should be abandoned by everybody, according to Dr. Henry W. Whitman, of the Mayo Clinic in Rochester, Minn., who holds the habit responsible for most cases of palsy.
WHAT keeps the ocean briny? The 485 known volcanoes of the world, spouting yearly more than a hundred million tons of hydrochloric acid, combine with the rivers to salt the sea. The rivers bring down quantities of sodium which unite with the acid to form sodium chloride or common salt.
ELECTRIC heat warms the newest automobile windshield wiper to help it clear snow and sleet from the winter driver’s path of vision. In appearance it resembles an ordinary wiper, and is attached in the conventional way. But the jointed metal arm contains a concealed heating coil, connected with wires from the car’s battery.
IF A swimming pool of ordinary size were contaminated with sediment amounting to one billionth of its volume, the effect would hardly be noticeable; but the waters of the deep sea, which suspend this proportion of sediment constantly, contain in all some 234,000,000,000 tons of matter.
AN AIRPLANE pilot’s efficiency depends upon the perfect functioning of his thyroid gland, and not alone on his eyesight, heart condition, and other factors associated with flying fitness. That is the pronouncement of Dr. Leon Asher, of the University of Berne, Switzerland, after experiments with animals.
THIRTY novel coal cars, designed for the largest freight train ever operated on an English railroad, are the latest equipment of the London, Midland and Scottish Railway. Built of steel, they are shaped more like motor trucks than typical freight cars.
GUESSWORK is eliminated by a new automatic machine that looks critically through an electric eye at a photographic negative, tells what grade of paper is best suited for making the finished print, and even announces the proper length of exposure to light in the printer.
WITH sides and hood of fabric which can be easily detached, and with a body structure that allows the machine itself to fold up quickly and easily after a few bolts have been removed, a three-wheeled automobile designed in Germany is capable of being stored in a very small space.
A RUN of sixty years without a stop is the record claimed for the “Big Ben” of Berlin, the giant timepiece in the tower of the City Hall. One reason for the clock’s efficiency is that it is inspected and adjusted once a week by its makers, in accordance with an agreement with the city authorities.
PROBABLY few people, when they make out checks, realize that the history of the dollar sign inscribed thereon has been a source of controversy for decades. The actual word dollar has been traced readily to the German word “thaler,” referring to a piece of silver which was in common use in Europe as long ago as the fourteenth century.
WAKING in the morning to the tune of a dreamy waltz or a stirring jazz selection, instead of to the clamor of an alarm bell, is now made possible by a novel combination alarm clock and phonograph. The outfit resembles a portable phonograph, with a clock set into the case.
GIVING cut flowers medicinal baths to prolong their existence is a waste of time, concludes the Boyce Thompson Institute for Plant Research, Yonkers, N. Y., after a survey of the problem. Though flowers are not known to develop headaches, there has been a popular notion that they will be stimulated by baths of aspirin and various other chemicals.
ARRIVAL of an innocent baby may cause the father to lose his hair, Dr. Donald B. Rogers, of Neenah, Wis., has reported to the American Medical Association. He describes a patient who shortly after the birth of his first child lost most of the hair on the left side of his head.
ANTS, like men, may go insane, according to the observations of Dr. Robert Staeger of Berlin, Germany. Watching an ant colony, he saw one individual that was doing circular acrobatics, attacking its fellows, and otherwise acting queerly.
THREE shells bursting near the plane at ten-second intervals, and producing clouds of black or yellow smoke, mean “Land at once” to a Cuban aviator. The warning is the recently adopted way of notifying him that he is to descend immediately and explain why he has violated one of the local air rules.
HIGH above the waters of the Arkansas River, across the Royal Gorge that in places attains a depth of 2,600 feet, cables are being slung for a suspension bridge which, it is said, will be the highest in the world when completed, near Canon City, Colo. Huge, openwork steel towers sunk into solid concrete masonry on either side of the gorge support the work.
NEW “armored car” banks have been introduced by a Los Angeles, Calif., banking institution to accommodate clients who are unable to get away from work long enough to reach even a neighborhood branch bank. The banks-on-wheels roam through the suburbs of the city continually during banking hours, and the system accounts for a scene becoming more familiar every day there.
TRAVEL by steamship is far safer than travel by airplane or by train, according to a recent accident report by the United States Bureau of Steamboat Inspection. The report shows that for every 7,000,000 passengers carried by steamship during ten months of 1929, only one life was lost; while one life was lost for every 150,000 passengers carried by tail.
IDENTIFYING the stomach by an X-ray fluoroscope may become a future method of criminal detection rivaling that of fingerprinting. In a study of normal stomachs among students of the University of California, Dr. Robert O. Moody and his assistants found four distinct types of the healthy stomach, with numerous gradations in between.
A FEW months ago a Soviet plant wedding between rye and wheat took place in the laboratories of the Minsk Botanical Observatory in Russia, and the offspring, says the Leningrad Red Star, is a hybrid grain of such unusual qualities that it may turn the Russian grain industry inside out.
DRUNK on honey, a swarm of bees held up traffic on a railway line for nearly twelve hours. Near the town of Karlovac, in Serbia, a switch engine tried to move a freight car and derailed it. A jar of honey was cracked and the honey flowed out on the ground.
THE self-reliance of the individual body cell was demonstrated by recent experiments of Miss Honor B. Fell, working at the Strangeways Laboratories in Cambridge, England. She succeeded in isolating tiny pieces of cartilage gristle from the six-day-old embryo of a fowl and furthering their growth into normal bone in a test tube.
TO TEST the mental agility of bus drivers, the Paris police department now employs the “perceptotaquimeter,” an invention of Professor Emilio Mira, of Barcelona, Spain, which measures the ability of a driver to judge the speed of approaching vehicles.
FROM hard cider to silk is a far cry, but according to Professor D. B. Keyes, of the University of Illinois, the sour acetic acid which changes cider to vinegar will play a major part in a new process for making artificial silk developed by him in collaboration with E. P. King and Sherwood Swann of the same university.
SCIENTIFIC identification of bandit cars by the tracks of their tires is facilitated by a new photographic “fingerprinting” method developed by David Chapman, attached to the Sheriff’s Office in Los Angeles, Calif. It is based on the simple procedure of placing a try-square beside the imprint of the tire tread on the road when the imprint is photographed.
PARACHUTES will be a part of the equipment of the United States Army Air Corps’ pilotless gliders in the future, according to a recent announcement. These gliders are towed into the air by airplanes and released. Then they serve as targets for antiaircraft shells. Should the artillery fire miss the costly craft, they are likely to be destroyed by a rough landing.
WAITING in vain on a street corner for a cruising taxi need no longer be the lot of citizens of Rome, Italy, where street telephones have been installed to connect the prospective passenger with the nearest taxi station. Lifting the receiver flashes a signal light in the station.
"HOT DOGS” with complexion varieties worthy of a beauty parlor’s ingenuity were displayed not long ago at a meeting of the American Institute of Meat Packers in Chicago. Dyed in shades ranging from blond to brunette, with countless gradations in between, the flapperish frankfurters showed their seasonal styles like mannikins in a Paris fashion show.
CONSTRUCTION of two 600-foot electrically driven passenger liners, the first of their kind for transoceanic service, will begin soon in the yards of the Newport News Shipbuilding and Dry Dock Company, Newport News, Va., for the Dollar Steamship Line.
EIGHTY or ninety miles above the ground, three great belts of electric current are continually swirling like tidal floods above the earth, creating the equivalent of millions of horsepower. This conclusion was announced recently by Dr. E. O. Hulburt, of the Naval Research Laboratory in Washington, D. C., a laboratory which has been engaged for several years in studying the electric and magnetic properties of the earth which may affect radio transmission at sea.
AFTER a year of lonely wandering through the wilds of China, unaccompanied by any other white man, Herbert Stevens, English ornithologist, arrived at Shanghai recently with more than 11,500 "specimens which he had collected for the Field Museum of Natural History, Chicago.
HEAVY canvas and small bits of rope constitute a device invented by a Chicago woman to extricate an automobile when it is stuck in sand, mud, or snow. This easily portable “tractor" is simply a length of canvas, slightly wider than the tire of a car, with crosspieces of tar rope stitched at five-inch intervals.
SHIPPED in separate compartments to keep them from devouring one another, fourteen giant cannibalistic tarantulas captured on Ancon Hill, Canal Zone, Panama, arrived recently at their new home in the Reptile House of the Bronx Zoological Park, New York City.
AN INNOVATION in firefighting equipment is a “baby engine,” about half the size of the usual fire truck, designed by Sir William Morris, noted British motor car expert. Capable of a speed of fifty miles an hour, its purpose is to dash ahead of the heavier and slower apparatus in response to an alarm.
UNLOADING 8,000 quarts of milk in ten minutes with only one man conducting the operation is the record claimed for a huge “vacuum bottle” milk truck recently introduced in New York City and pictured above. This vehicle is used in transporting the milk from the dairies to the pasteurizing and distributing plant.
WITH the advent of night flying, a special type of electric searchlight known as the “ceiling light” has been employed at airports and landing fields to measure the height of low clouds for the information of pilots flying in darkness. The ceiling light is mounted on a pedestal and trunnion, so that the light can be elevated at any angle desired.
PETROLEUM, in the future, may supply not only the fuel for automobile engines, but also the rubber for their tires, the material for the raincoats of their passengers, and butter substitutes for picnic sandwiches. Moreover, it may provide soap for use by motorists after a dusty day in the country.
STATISTICALLY speaking, there is only about four fifths of one physician for every 1,000 men, women, and children in the United States. According to a recent Government survey, 149,521 doctors now are practicing among the 118,127,645 of this country’s population.
A CYPRESS tree in Tallahassee, Fla., now grown to enormous height and to a girth of fifteen feet, may well lay claim to an antiquity rivaling that of the famous California redwoods. Professor Herman Kurz, of the Florida State College for Women, asserts that this giant cypress is between 2,000 and 2,800 years old.
TO DELIVER to customers loaves of bread neatly sliced and ready for the table or for sandwich making, a baker of St. Louis, Mo., has invented a machine which can divide a loaf into twenty-nine even slices with one slash of its blades. Requiring only one operator, it can cut 1,000 loaves in an hour.
A COMPLETE toilet outfit, including running water, may be carried about as easily as an overnight bag if the portable kit recently shown at a Paris exposition proves as serviceable as is claimed. The equipment consists of a small metal box, divided into two compartments.
SPRAYING a tiny jet of perfume when its plunger is pushed down, a novel atomizer resembling a cigarette lighter in appearance may be carried in a woman’s hand bag, it is said, without danger of spilling its contents. Its nozzle is covered with a cap which is released by a plunger.
“IDENTICAL” twin baby girls recently served Yale psychologists as subjects in an experiment to determine whether training hastens the development of brain and nervous capacity in very young children. The investigators trained one of the little girls, at the age of forty-six weeks, to climb a set of five steps every day.
HOLLOW lamp-posts, to act as “subsoil chimneys,” have been suggested by E. J. Silcock, an English engineer who headed a commission which investigated the cause of a mysterious explosion that blew up several city blocks of London pavement some time ago.
THE green coating on copper domes and spires of city buildings can be traced to the action of sulphuric acid in coal smoke, state Dr. W. R. J. Vernon and L. Whitby, of the Chemical Research Laboratory of Teddington, England. The age-film, known as “verdigris” or a “patina,” is composed of basic copper sulphate.
THE frozen ruins of what was once a large Eskimo settlement on St. Lawrence Island in the Bering Sea have lately been explored by two American archeologists, who found there evidence of a culture in the Arctic that may date back a thousand years or more.
LARGE type cannot be read faster than medium-sized type, according to Professor Donald G. Patterson, of the University of Minnesota. He recently made tests upon 320 sophomores at the University. They were given paragraphs printed in six-point, eight-point, ten-point, twelve-point, and fourteen-point type.
SLEEPING with the mouth open is apparently as bad for crocodiles as it is for mankind. For as the green monster slumbers with its jaws ajar, the dread tsetse fly, carrier of the sleeping sickness microbe, is likely to enter. The disease is not transferred by a bite, but a bite may annoy the crocodile so that it wakes up and snaps at the fly, swallowing it and the germ.
A HIGH-SPEED runabout of an unusual design is being built for the private use of Phillip Chancellor, heir of a wealthy New York family. While it will not attempt to shatter the world’s speed record of 231 miles an hour set by Maj. Sir. H. O. D. Segrave, it will be able to amble along at 125 miles an hour, quite fast enough for the requirements of city or interurban travel.
A COLLAPSIBLE rowboat, lighter and more portable than a canoe, has been introduced in England. Weighing a bare thirty pounds, it can be folded so easily and compactly that almost any adult can lift it single-handed and pack it away in one side of a garage.
RESTRICTIVE law, the popular American panacea for almost any trouble, turns out to be bad medicine with which to cure the automobile speed problem. Neither the motorist nor the pedestrian is benefited by arbitrary and frequently ridiculous limitations on speed.
The author of this article is Professor of Otology in Cornell University Medical School. He tells how science may rescue millions from the borderland of deafness.
GEORGE B. McAULIFFE
OF THE hundred million and more persons in this country yearly subjected to the general noise of life, one out of every six has defective hearing. The fact is so startling as to merit restatement. Although there are only 55,000 deaf mutes in the United States, more than twenty million men, women, and children suffer from deafness in some degree.
Most Any Out-of-Date Receiver Can Be Improved in Volume and Tone Quality by a New Speaker and Audio Amplifier Equipment
ALFRED P. LANE
WHAT shall I do about the old radio set? That question has almost as many answers as there are types of out-of-date receivers. To find the correct one in any particular case, a number of factors must be considered. First is the age and present condition of the receiving equipment.
Where to Look for Troubles That Cause Queer Noises or Fading Volume—How to Test Electric Sets for Hum
Useful Hints for the Radio Fan
IN MANY ways the dynamic cone speaker is an extremely rugged mechanism. The field magnetism, since it is produced by the flow of an electric current, never weakens so long as the current flow is maintained. The dynamic speaker has definitely improved tone quality.
TO DETERMINE the cost of current to operate an electric set, first shut off every house light. Then, watching the electric meter, turn on the radio set and count the number of turns the disk in the meter makes in one minute. Shut off the set and, by experiment, find the number of lamps which must be turned on at once to make the meter disk rotate at the same rate.
MANY B batteries produce grating and scratching noises some time before they are actually exhausted. Such noises can be eliminated and the useful life of the battery extended by connecting across the block a two-microfarad filter condenser of the type ordinarily sold for use in building a B eliminator and power amplifier circuit.
THE critical point in any full electric receiver—the point where hum is most likely to be produced—is the detector circuit. Consequently whenever an A. C. receiver begins to develop a steady hum the detector tube should be investigated. In many types of circuits, when the set is first turned on, a hum immediately develops and then dies out as the detector tube heats to operating temperature.
How Receivers Draw B Voltage Supplies from Light Sockets
ALL radio receivers, however designated, actually operate on direct current. Though alternating current flows into a modern electric set from the light socket, direct current still does the work in the radio receiving circuits just as it did in the days before light socket operation was possible.
Improvements that give the simple suburban bungalow in America a more complete system of sanitation than is found in many an Old World palace or mansion.
ROGER B. WHITMAN
PLUMBING, first used because it saved the labor of carrying water in buckets, has developed into a national household safeguard of health, as well as an indispensable household convenience. Some dwellings now are equipped with a bathroom for every bedroom and one or two more for general use, while in virtually every modern home are kitchen and laundry fixtures designed for labor-saving and water supply and waste outlets placed where they will be most serviceable.
THE extraordinary photographs on this page were taken during a recent test of a new system of huge parachutes designed to support an airplane in the sky—an experiment from which the pilot of the plane, M. J. McKeon, of San Mateo, Calif., barely escaped with his life.
Gus Explains How Auto Designers Get More Pull Out of the Engine Cylinders by “Continuous Levers”
"ONE hundred horsepower!' Joe Clark whistled to himself as he read the specifications of one of the new cars. Gus Wilson, veteran auto mechanic and Joe’s partner in the operation of the Model Garage, merely grunted. His mouth was too full of ham sandwich for articulate expression.
LOCKED away in an old fair building in Balboa Park, San Diego, Calif., stands the Diamond Tally-Ho, a stagecoach that ran for many years between that city and the little mining town of Julian. It is stripped of lamps, curtains, and boot sides.
How to Sharpen Thin-Bladed Tubular Runners— Keeping Bent Wood in Shape and Other Hints
GEORGE H. VAN WALTHER
ESPECIALLY true of winter sports—skating, skiing, and ice boating—is the statement that success depends upon keeping ones equipment in first-class condition. Skates with the old-fashioned wide blade were ground at the beginning of the season and not touched again for the remainder of the winter.
How to Build a Timber Stop That May Save a Costly Crash—Other Ideas Car Owners Have Found Useful
MOST home garages are lightly constructed. While strong enough to resist ordinary strain, the entire back wall of the garage may be wrecked by a blow from the car bumper so light that the bumper itself is not damaged. Figure 1 shows how to make a stop to avoid such trouble.
SOMETIMES a break in a spring that presses a brush against the commutator on the starting motor makes the starter inoperative. Figure 2 shows a temporary repair. Cut a strip of rubber from an inner tube and pass it through the openings in the motor frame as shown.
AN ORDINARY mousetrap (Figure 3) can be converted into an effective auto burglar alarm. Two wires with spring clips attached to their outer ends are attached as indicated. One clip is attached to the live terminal of the horn and the other to the metal frame of the car.
A CONSTANT stream of warm air can be directed against the windshield to prevent fogging and frosting (Figure 4). Raise the rear edge of the engine hood on each side enough to insert a small block of wood. This will produce an opening along the top rear edge of the hood through which heated air from the engine flows and strikes the glass.
FIGURE 5 shows an easy way to make a rest for the hood when it is opened. The only mechanical work needed is the hack-sawed slot in the edge of the cowl and two holes for bolts that hold the angle pieces to the dash. The straight piece and the two angle pieces are stock items from standard toy mechanical construction sets.
Construction of Boudoir Chair Gives Practice in Use of Motorized Tools
WILLIAM W. KLENKE
MOTORIZING the home workshop has made it possible for the amateur craftsman to construct many furniture projects—such as the boudoir side chair illustrated in Fig. 1— which are more elaborate and attractive than those that ordinarily can be made by hand.
DEEP scratches that go clear through the finish on pieces of furniture can be removed if the right procedure is followed. First, stain the wood in the scratch with a matching stain. Allow the stain to dry for about 24 hours, and then coat the scratch carefully with a first-class grade of furniture varnish.
Use of Familiar Materials Simplifies Many Otherwise Difficult Shop Operations
MONEY in the and machine time often shop can through be saved the use of familiar and inexpensive materials which are not ordinarily employed in routine operations. A number of short cuts of this type are illustrated. Some odd jobs for paper, other than as a friction material, are illustrated in Fig. 1. By using the paper in the manner demonstrated at A, the clearance as well as the cutting ability of dies can be gaged before starting work, and troubles can be more readily analyzed than from the metal blank.
AN EFFICIENT electric muffle for heat treating metals in the home workshop can be made from the common reflector type of portable electric heater designed for household use. This type of heater has the resistance wire wound on a porcelain tube.
EVERY mechanic knows that in marking work a much larger surface is usually chalked than is necessary because the exact position is not known until the surface gage is used. With the chalk holder shown, the chalk marks the exact place that the scriber will follow and thus no time is wasted.
IF YOU remove the center from the headstock of your lathe for any reason, plug the hole with a piece of clean waste to keep the dirt out. A flat drill will often drill hard, tough materials better than a twist drill. When a drill squeaks in the hole, it is usually a sign that the side clearance has worn away.
WOODWORKERS often like to try their hand at copying a fine specimen of antique furniture—such a piece, for example, as the low boy illustrated. The original, which was made about 1740, is noteworthy for its grace, and because of its limited size would look as well in a small as in a large room.
WHEN the projecting case and knob of an ordinary cupboard catch or latch is objectionable, the handy man will find tucked away upon the shelves of the nearest large hardware store just the substitute he needs—a flush ring catch. A flush catch leaves the face of the door and of the bookcase, cupboard, or chest of drawers with no projection to mar its smoothness.
BY INCASING its handle in embossed leather, a plain paper knife can be converted into an attractive ornament for any desk, as shown at the right. The embossed design is similar to one used in making the leather book ends previously described in this series (P.S.M., Jan. ’30, p. 100).
FOR simplicity of construction and general adaptability, the Swiss breakfast set illustrated probably has few equals. The table and chairs, which are an exact copy of original Swiss furniture, are the handiwork of Fred Hauser, of Pasadena, Calif.
WHEN it is necessary to grind an oval form—as for flanging some light tank heads—a machinist in a small shop is likely to be at a loss as to how best to get the outline true without undue expense. A unique method is to chuck a grinding wheel in a lathe and use the compound rest as a work support.
TO REMOVE cement and plaster from tile floors, first scrape off as much as possible and then apply muriatic acid in the proportions of one part acid to ten parts water. Add the acid slowly and cautiously to the water and handle the mixture with care.
HIGH-GRADE model railway locomotives and the various cars are painted by a dipping process, and the enamel is baked on to give an attractive and durable finish. Repainting is, however, often necessary. Cars will become derailed and collisions will occur even on the best regulated model railway, so that the enamel in time becomes chipped and scratched.
IN ORDER to accomplish some milling operations it is often well to use extra wide cutters. A method for interlocking two or more cutters is shown. The greater part of the work is done on the surface grinder. In cutter No. 1 cut two parallel slots 3/32 in. deep, using a 6-in. medium grade elastic grinding wheel ⅜ in. wide.
DIFFICULTY in strapping and the possibility of error in attaching a laid out job to the faceplate on an engine lathe are removed when the nonslip faceplate bolts illustrated are used. The bolts are made from ⅞-in. stock, as the head of the bolt is ⅞ in. square.
DURING the winter months model airplane flying usually has to be confined indoors. This fact was responsible for the designing of the 5½-in. indoor flying model illustrated—a midget plane that well deserves the name of Parlor Scout: Because of the simple construction of this model, it is a good starting point for the boy who has had little or no experience in model building, yet its unique design and unusual flying qualities make it a worthy project for the expert.
FOR storing a boy’s sporting equipment and various treasures, this modernistic looking locker or closet is just the thing. Any handy boy can make one for himself. First, the two ends ¾ by 12 in. by 5 ft. 1¼ in. should be made. Cut the decorative angles accurately, but, if extreme simplicity is desired, the embellishments may be omitted and the ends made the full 12 in. wide, which will allow each shelf to be made 1 in. wider.
A BETTER flux for the home workshop than the ordinary “killed spirits” may be made by dissolving stick zinc chloride in methylated spirits. The stick zinc chloride is sold in sealed glass tubes containing 1 oz., for about twenty-five cents.
BY USING the easily made cabinet shown, it becomes a simple matter to keep stationery clean and where it will be readily accessible. Pine or basswood can be used in the construction. The top, door, and bottom are cut from ½-in. stock; the back and shelves from ¼-in. stock; and the ends from ⅜-in. stock.
IF MODERN methods are employed, it is not difficult to refinish an automobile at home. Quick-acting chemical paint removers and electrically operated paint sprayers are rapidly replacing tedious scraping and brushing operations.
FOR boring holes in wooden line shaft boxes, in wooden split pulleys, or in any parts where a true, deep hole is required between two pieces of wood, first make a pencil guide mark on the abutting face of one piece and saw the mark out accurately so as to leave a groove about 1/16 in. deep extending clear across the block, as shown.
THE toy illustrated, which can be made cheaply, will surprise you with its lively actions and clog steps. Grown-ups as well as children will marvel at the realism of this toy dancer. The body is made from one piece of ¾-in. gumwood, or any available wood will do.
THIS design of a clothespin carrier won first prize in the elementary metal working division of the shop problem competition for teachers conducted recently by the Educational Department of POPULAR SCIENCE MONTHLY. The design is the work of Mr. W. A. de Vette, of the manual training department of the Wilson Junior High School, Erie, Pa.
A PIECE of leather glued to the top of the oilstone case makes an excellent strop for putting the final edge on a tool. It is desirable to make a second cover to fit over the leather and protect it from the dust, if the oilstone is not kept in a dust-proof drawer or cabinet.
THIS defect may be the result of repeated coats of paint and varnish. Inspect the screws of the hinges carefully to be sure that they are driven home. If the door still gives trouble and the width of the crack along the lock joint will permit it, loosen the screws in the jamb and insert a piece of pasteboard between the butt (hinge) plate and the jamb.
A MINIATURE stage, besides being a plaything for children, is of value to anyone, young or mature, who is interested in marionettes or who is a student of costuming, dramatic grouping, or scenic effects. As the scale is an inch to a foot, the stage illustrated is large enough for really worth while presentations and allows ample room for properties and scenery constructed upon the same scale.
INDIVIDUAL hat trees are used in department stores not only as exhibition stands but also to preserve the shapes of the hats. These little stands conform to the rounded shape of the crown and hold the brim out of contact with the shelf. As will be noted from the sketch and photo, these trees are simple in construction and can be put together in a few minutes.
THERE are at least three good reasons why the amateur painter should learn a few simple tests for paints, even though carrying them out may require a little more care and trouble than just stirring up the mixture in the can and applying it. The first reason is that a knowledge of these tests puts a man in a position to recognize good paint from bad and to be a discriminating purchaser.
HOW well can you solve block puzzles? The two illustrated below are easy to make and will perhaps give you a surprise in working out the solutions. The wood used can be either ½ or ¾ in. square, and dimensions for both sizes are given. If the two puzzles are cut from the same stock one set should be marked in some unmistakable way.
WHILE it is usually bad policy to use too much force in applying a wrench on nuts, it is occasionally necessary to pull nuts exceedingly tight. Cases in point are bolts for holding tools in stamping machines, draw rods for pulling bushings into place, or for loosening nuts that have rusted.
GUTTERS, downspouts, and the like should not be painted until particular care has been taken to remove all rust, scale, and dirt with a wire brush, putty knife, and sandpaper, and by scrubbing with kerosene, if necessary. It is important to remove all rust; for rust, even if painted over, will eat its way through the paint.
Deceptive Trout Flies Have Soft Rubber Detached Bodies
R. P. LINCOLN
BY USING a small sliver of light-colored automobile inner tube for the detached body, it is possible to make realistic trout flies inexpensively and easily. Trout fishermen who believe that the artificial fly should be a counterpart of the living insect agree that the detached body of the fly is of the utmost importance.
CASTERS which have a horn projecting into a hole can be kept from falling out when the furniture is lifted by wrapping friction tape or rubber bands around the stems. To tighten a caster of the socket type, remove it, wrap tough paper or cambric around the wood over which the socket fits and glue well.
WITH a little shaping, discarded dental tools can be turned into useful additions to the home workshop tool chest. Because these tools and drills must stand the strain of cutting porcelain and bone, they lend themselves well to many of the delicate and difficult little jobs that the home worker so frequently encounters.
THE easily made glass mount illustrated permits the inspection of moths and butterflies from both sides and also is effective as a wall or mantel decoration. Cut a strip of cardboard from ½ to ¾ in. wide and sufficiently long so that it can be bent into a square or oblong that will allow a ½-in. margin all around the specimen.
WHEN boards are to be glued up on the workbench, it is often difficult to keep the cabinetmaker’s bar clamps from turning over. Blocks, cut from any hard wood as shown, will hold the clamp upright. Where the clamps are not all of the same make, blocks are provided so that all will rest at the same height from the BENCH.
AS THE rigging on our model of the Bluenose nears completion, the little fishing schooner takes form and begins to display its full beauty. Since the rig of a schooner is its most characteristic feature, and since cleancut, seamanlike rigging is always the distinguishing mark of a high-grade model, it is imperative that the rigging on the Bluenose be assembled with meticulous care.
WITH the expenditure of a little time and money it is possible to equip your machines with self-feeding grease cups of the type illustrated. The cup fits on the high pressure type of fittings and is filled by applying a high pressure grease gun to a similar fitting on the side of the cup.
FIXING metal furniture leg slides to the guide of a marking gage will facilitate the marking of a straight line on rough wood. The needle marker must be advanced as much as the guides project above the surface of the guide face. This will keep the graduations on the side of the marker accurate by counteracting the height of the slides.
MAGIC fascinates most of us but often leaves us with the feeling that all good tricks are too difficult or complicated for us to attempt. The spiritphone illustrated, however, is easy to construct and still easier to operate, and is one of the most effective tricks for the amateur magician.
BESIDES providing a comfortable window seat, the bench illustrated has an added advantage in supplying a roomy chest for the storage of books, sheet music, and clothing. It may be made of any hardwood such as oak, ash, or mahogany to match other furniture; or of a more easily worked wood as red gum, whitewood, or white pine if it is to be painted or lacquered.
THE home workshop enthusiast who delights in books can quickly learn to rebind damaged or worn editions and make bound volumes of his magazines that will safeguard them indefinitely. Let us take, for instance, six months of our favorite—POPULAR SCIENCE MONTHLY— and see how easily a bound book can be made.
OFTENTIMES we are confronted with the not altogether pleasant job of removing a broken set screw’. Aside from the unpleasantness of the job, it is usually difficult and presents somewhat of a puzzle as to the correct procedure. When a set screw’, holding a pulley in place or used in some similar part of a machine, breaks off, it invariably twists off close to or even below the surface of the threaded hole.
ASK any watchmaker what his most useful tool is, and nine times out of ten he will show you a collection of punches together with a G-shaped stand, the whole of which is usually knownas a “staking tool.” With this design in mind, the writer made the device illustrated, and has found it well worth the time spent in its production.
A FIXTURE for holding small pulleys, sheaves and similar work at an angle for drilling oil holes or set screw holes can be made from wood as shown. The foot piece is notch ed in the center to keep the work from moving sidewise. In shops where even a moderate amount of this class of work is handled, several such fixtures will soon pay for themselves.
AN EFFECTIVE cleaner for removing oil and grease spots from concrete driveways and garage floors is tri-sodium-phosphate, similar in appearance to common table salt. Wet the concrete thoroughly, then sprinkle the chemical evenly over the spots and let it stand for several hours.
FLIES, cockroaches and orchard insect pests killed by radio is a new marvel announced the by the New Jersey Agricultural Experiment Station at New Brunswick, N. J. Recently Dr. Thomas J. Headlee, entomologist of the station, demonstrated how insects placed in a glass tube and exposed to powerful radio waves from a high-frequency transmitter, died in a few moments.
INCA gold, believed to have been hidden for nearly four centuries, is being sought in a high pass of the Andes Mountains, just north of Peru, as the result of a recent accidental find by a party of prospectors. A cave containing ancient skeletons and an Inca idol, symbolic of the sun, suggested that the region may contain the fabled gold and jewels, valued at $15,000,000, which were collected to ransom the last Inca king of Peru, Atahualpa, from the Spanish conqueror, Pizarro.
WHAT sort of beer the Pharaohs drank, whether it was light like Pilsener or dark like Münchner, has been determined precisely by Prof. Johannes Gruess of Berlin. Taking to his laboratory a consignment of Egyptian jugs and bottles dating as far back as 1,700 years before King Tut, sent by H. E. Winlock of the Metropolitan Museum in New York City, Professor Gruess subjected them to severe analysis.