The Gleason family were holding their regular January 1 round-table conference to try to find out what had happened to their money and their plans for getting ahead in the world during the past year. Also, to lay financial plans for the new year.
An Exact Comparison between 1929 and 1930 Receivers Is Given by Test Measurements in Institute Laboratory
COLLINS P. BLISS
A VERY interesting comparison between the radio receivers produced last year and the new models now being sold is provided by checking Popular Science Institute’s test records against each other. Aside from appearance which, of course, is a matter of individual preference, a radio receiver is good in proportion to its ability to bring in stations, to choose between stations, and to faithfully reproduce the music or speech with plenty of volume.
"THE letters you recently published about a problem in airplane speed were interesting. May I suggest another problem for someone with a taste for figures to solve: “An automobile circles a speedway twice. The first lap is covered at the low speed of ten miles an hour; the second lap at fifty miles an hour.
Great Cities, Menaced by Deafening Din of Modern Inventions, Move to Safeguard Public Nerves and Health
E. E. FREE
DOES noise endanger civilization? Not even noise-haters have suggested so drastic a query, yet they might do so without exceeding the possibilities. Recent psychological tests have shown that one of the effects of noise may be to over-stimulate the body, nerves, and mind.
Authorities in Seventeen Fields of Research Take Stock of the Years Outstanding Advances in Discovery and Invention
MEDICINE AND SURGERY
MINING AND METALLURGY
IMPROVEMENTS in apparatus, circuits, and methods continue to extend the limits of communication and to improve its speed, quality, and dependability. Illustrative of this is the proposed transatlantic telephone cable, the main link of which will probably extend 1,800 nautical miles from Newfoundland to Ireland.
A Strange Mystery of Prehistoric Americans Who Erected Cities and Deserted Them—No One Knows Why
SOARING over the tropical jungles of Central America a few weeks ago, the man who has become the living symbol of one of the latest phases in human progress looked down upon the crumbling remnants of the oldest American civilization. In twenty-five hours of flying through the sultry air above Honduras, Guatemala, and Yucatan, Colonel Lindbergh, accompanied by Mrs. Lindbergh and scientists of the Carnegie Institution, of Washington, D. C., discovered ruined cities of the ancient Mayan Empire which could not have been reached by a ground expedition in less than five years.
PHOTOGRAPHS of the complicated architecture and machinery inside a living cancer cell or other similar unit of life have been made by the remarkable ultra-violet ray microscope, most powerful magnifying instrument in the world. This achievement is the work of Francis F. Lucas, internationally-known metallurgist of the Bell Telephone Laboratories, New York City.
TRAFFIC jams at the Panama Canal would be averted by a $12,000,000 dam proposed by Governor Harry Burgess, of the Canal Zone. The proposal has just been approved by Secretary of War James W. Good, and Congress will be asked shortly for $2,000,000 to begin construction.
How Improved Cameras and Film Have Made Amateur Producers of 150,000 Americans
ROBERT E. MARTIN
THE other day, a home movie enthusiast in California began making a unique “Jack-and-the-beanstalk” diary of his little daughter. Once a month, he will “shoot” a small strip of film of her standing in the same place. He plans to continue this until she is grown.
MY FIRST flight was made on a barn door. That was in 1909. I was a little fellow, twelve years old. Bleriot, my great hero, had just flown the English Channel. From newspaper accounts, I got the impression that the wings of his monoplane were flat and made out of wood—the same as a barn door.
A SKYSCRAPER now rising in the heart of New York’s financial district will offer its occupants a novel type of delivery service. Each broker with the building will be assigned a cage in the basement. Stocks, bonds, and checks to be delivered to his office will be brought to that cage.
A Pictorial Story of Shipbuilding and Seafaring, from the Ancient Galley to the Modern Ocean Liner
EVER since the first primitive man to float down a river astride a dead tree discovered that he could propel himself by paddling with his hands, the story of man’s conquest of the waters has been tinged with romance and adventure. The illustrations on the following pages record the most fascinating phases in the history of seafaring.
The World's Largest Dirigible and Flying Boat Make Good—New Airplane Records and Promising Inventions
A NEW “world’s largest” dirigible, Britain’s oil-burner R-101, left its hangar at Cardington, England, recently for a successful maiden flight. Its first 300mile cruise, followed by a longer flight a few days later, seemed to contradict recent assertions by at least one prominent British engineer that the craft was underpowered, structurally unsafe, and “already obsolete.”
OIL-BURNING airplane motors are to replace gasoline engines in all French military planes, following their official adoption by the French Air Ministry. The plan is to make the gradual substitution first in the school training planes, and later in all army and navy aircraft.
AN INSTRUMENT that will project sound waves from an airplane to the ground, receive the echo, and translate the elapsed time into the number of feet that the airplane is above the earth, is now being tested in experiments conducted at the University of California, Los Angeles, Calif. Leo P. Delsasso, inventor of a naval sonic depth-finder, is engaged in the work of applying the principles of sound reflection to this new type of altimeter.
SHOOTING at an invisible target with an aerial camera, Capt. A. W. Stevens, United States Army Air Corps photographer, recently obtained the most distant photograph ever made. The target was Mount Rainier, 14,000-foot peak in the state of Washington, and the distance was 227 miles from the Oregon point where Captain Stevens was flying at an altitude of nearly 17,000 feet.
TAKING off from the ground with the wings of his plane spread wide, the pilot of the future may operate a control to make the wing surface narrower for speed flying, and operate it a second time to restore the wings to their full size for landing.
THE first commercial ambulance service by airplane has just been organized, according to an announcement of the New York City firm that sponsors it. It offers day and night service between New York and any point in the country having an adequate landing field.
BY A nonstop flight of nearly 5,000 miles, Dieudonne Costes and Maurice Bellonte, French airmen, have apparently shattered all records for a distance hop. Leaving Paris recently with Tokio as their announced objective, they all but completed the ambitious flight.
WITH 169 persons numbered in the official list of passengers and crew, the Dornier monster seaplane DO-X recently made a flight of nearly an hour over Lake Constance, Switzerland. A fouryear-old boy not counted in the records brought the total to 170 persons, by far the largest number ever taken aloft at once, either in airplane or dirigible, in the history of aviation.
New Tidal Theory Explains How the Planets Sprang from the Sun
ONE day, eons ago, as the lonely, planetless sun, a rotating ball of white-hot gases, was drifting through space, it was partly disrupted by the close approach and gravitation of another large, swift-moving star. The terrific attraction of the new star raised two enormous tides of gas on the sun, one on each side.
BACK from an expedition off the coast of Newfoundland, in which new methods of detecting icebergs were tested, Dr. Howard T. Barnes, of McGill University, Montreal, Canada, is reported to be working on a device for revealing fog-hidden icebergs to mariners through the agency of infra-red rays or “black light.”
AT LEAST five prominent rivals of the world’s tallest skyscraper, the 792-foot WoolWarth Building, are at this writing projected in New York City. Already well advanced in construction is the Chrysler Building of seventy-five stories, 850 feet.
FOR long-distance voyagers by airplane or airship, the maps similar to those studied in school geographies possess limitations when it comes to plotting courses. Such maps indicate directions, but positions of continents, their shape, and the distance between two points are inaccurate approximations.
Experts Model Human Organs in Plaster to Aid Study of Medical Science
IN THE old German toy-making town of Sonneberg is a busy shop where expert model makers, descendants of a long line of craftsmen, are turning their skill to the aid of science. There human skeletons, skulls, eyes, ears, limbs, and all other parts of the body are reproduced by the hundreds, to be sold to medical schools in many parts of the world for the study of anatomy.
A GROUP of business men and scientists in New York City recently witnessed a demonstration by Dr. Alger S. Riggs of a system of radio reception which he claims is entirely new. Dr. Riggs declares that special vacuum tubes he has developed, when used in his special circuits, give even better than normal radio reception without making use of many features hitherto thought indispensable.
SNUGLY lodged in the deep recesses of the Mammoth Cave in Kentucky, with a superheterodyne receiver and loop aerial set up beside them and seventyfive feet of sandstone rock above their heads, Dr. A. S. Eve and Dr. D. A. Keys, of the Department of Physics, McGill University, Montreal, Can., recently listened in on radio programs from Louisville, Nashville, and Cincinnati.
GURGLING like a choked gutter as they retreat into their burrows, monstrous, pipe-sized earthworms from four to six feet long and an inch in diameter are reported to have been discovered by a recent naturalists’ expedition in southeastern Australia.
PROF. R. H. GODDARD, Clark University physicist and inventor of a high-altitude rocket, can fire his sky projectiles from Camp Devens, Mass. Permission to use the field for rocket tests was recently granted by the War Department upon the application of the Smithsonian Institution, which is backing Professor Goddard in his experiments.
IN CAVES of the prehistoric Basket Maker Indians east of Kenton, Okla., Dr. E. B. Renaud, of the Colorado Museum of Natural History, found food cakes resembling the familiar doughnuts of a modem coffee shop, with the “hole in the center” and all.
TO WITHSTAND the terrific friction of traveling at a speed between 200 and 300 miles an hour, silk tires are being manufactured for a new racing car in which Kaye Don, British racing driver, hopes to set a new speed record at Daytona Beach, Fla., this February.
AFTER years of work on an instrument that will produce music when a person waves his hands before it, Prof. Leon Theremin, Russian scientist, recently adapted it to commercial use. It has broadcast music over the radio and is being demonstrated for sale to the public.
A HUGE "telephone booth on wings" has been added to the equipment of the Bell Telephone Laboratories, of New York City. It is an all-metal, tri-motored Ford monoplane equipped with unique apparatus for testing and improving radio telephone instruments and methods designed for the use of transport and air mail pilots.
A “LANDLUBBERS’ yacht club,” resembling a gigantic, saucer-shaped motordrome, is to be constructed on a dry lake bed covering fifteen square miles of territory near Tonopah, Nevada. Although there is not so much as a pond within one hundred miles of the town, the citizens are undaunted and are going right ahead with their plans for cruising and racing on the dry lake.
WARM floors, better circulation of heat, and an attractive appearance in a room are the chief advantages claimed for a new type of radiator now being made. Long and narrow in shape, the radiator is built so that it may be attached to the baseboard of a wall or recessed, partly or completely, at the floor line of a room.
UNIFORM acceleration—the elimination of jerky “pick-up’’—and the saving of wear and tear on shoes are advantages claimed for a new “rolling” type of automobile accelerator pedal developed by a Chicago manufacturer as a substitute for the usual button type.
“PLAYING the typewriter” will be a new musical accomplishment when composers avail themselves of a machine for writing musical compositions devised by an Italian musician-inventor. The novel “instrument” resembles an ordinary typewriter, but has sixty-four keys instead of the usual forty-two, and a series of buttons and levers controlling machinery that permits the writing of music in any key.
SYMBOLIC of the ancient struggle between the giant beasts that roamed the earth thousands of years ago and prehistoric man, the teeth of a woolly mammoth and two sets of petrified human brains were recently reported found side by side at Odinzowo, Russia.
A DISAPPEARING rubber roof that slides back and forth along the top of a motor truck, and, when not in use, is folded automatically and housed in a casing above the driver’s cab, is the invention of A. G. Schlicher, of Allentown, Pa. He says it will offer surer protection to perishable loads during rainy weather than the canvas tops ordinarily used for the purpose.
THAT rats are infested with fleas which carry bubonic plague and other dangerous diseases is generally known (P. S. M., Nov. ’29, p. 46), but few persons are aware that “man’s best friend,” the dog, plays host to parasites that menace the health of his master.
ALMOST twice the power developed by the old-time hand-stoked boilers was generated by one equipped with pulverized coal burners in a test conducted on the steamship Donau, of the North German Lloyd, which put in at San Francisco harbor on its maiden voyage from Germany some weeks ago.
HASTILY summoned to the Indianapolis Speedway when an automobile tire went flat in a recent nonstop speed test after only a few minutes use, a gang of sixty men, with three lengths of rope to which magnets had been attached, discovered the reason why the brick track, in its seventeen and a half years of use, had acquired the reputation of being hard on tires.
A LOUDSPEAKER in every classroom, bringing to the students important radio programs from a central radio receiver, or, at other times, messages direct from the principal; a cafeteria equipped with speakers that furnish music for the pupils at lunch time; and an auditorium in which the entire school may enjoy such programs in a body—these are innovations in a new $1,500,000 high school at Great Neck, New York.
"DE-WATERING” the fat from bulky limbs may be the fashionable procedure in the future for persons whose obesity is of a certain type. According to Prof. Julius Bauer, Viennese physiologist, many women whose legs are too stocky to be beautiful do not have fat legs, but merely watery ones.
REPLACING stoves and grate fires still employed to a surprising degree for heating in England, a new electric radiator designed to warm houses and offices at a reasonable cost is being introduced by the City of London Electric Lighting Company.
CARRYING within its case its own means of illumination, a new electric magnifying glass is designed as a handy aid in reading small print or in examining objects that require fine eyesight. The apparatus is fitted with glass at each of its circular ends.
A SHERLOCK HOLMES of the British detective service in India has laid to his credit the exposure of a banknote counterfeiter by employing the methods of microchemistry. R. M. Ghosal, principal of the Detective Training School at Insein, Burma, was called to investigate the lair uncovered by a police raiding party.
THE fastest reader is one who grasps the meaning of sentences almost entirely by eyesight, without mental pronunciation of the words before him. This is the conclusion of Professor Walter B. Pitkin, of Columbia University, New York, as the result of recent tests.
HAILSTONES larger than tennis balls bombarded Durban, South Africa, during a recent terrific hailstorm, causing damage estimated at $3,750,000. Reliable witnesses in various parts of the world have reported seeing falling hailstones as large and weighing from half a pound to a pound or more, but this is believed to be the first time that one has been photographed.
AROUND fortress, built in the early decades of the nineteenth century at Folkestone, on the southeast coast of England, has been converted by an enterprising constructor into a modern apartment house. The fortress is part of the famous Martello towers that were erected to repel a potential French invasion at a time when the name of Napoleon was terrorizing Europe.
“SIGHT-SINGING,” a word used to denote the ability of some vocalists to read from a musical score without previous preparation, may assume a new meaning with the perfection of an instrument that makes musical sounds visible. By means of the novel device, developed by engineers of the Westinghouse Electrical and Manufacturing Company, students of the voice and also of instrumental music may be trained visually as well as orally.
“BRINGING home the bacon” was no easy task in what is now Nebraska about twelve million years ago, for in that dim day the “cornhusker” state was inhabited by hogs the size of automobiles. The fossil skeleton of one of these gigantic pigs, seven feet tall and twelve feet long, dug up in Sioux County, Neb., was recently mounted at the University of Nebraska.
“HE WAS a bold man that first eat an oyster,” said Dean Swift, author of Gulliver's Travels. No courage, however, is required to eat pink oysters, now that the New York State Department of Agriculture has given them a clean bill of health, following an investigation by its bureau of chemistry.
AN ATTACHMENT for an armchair that provides a convenient table for letter writing, eating meals, or card playing and that can be used also as a book rest has recently been put on the market by a Newark, N. J., manufacturer. The attachment consists of a flat piece of wood hinged to two sidepieces that are strapped to the arms of the chair.
AN UNUSUAL building that formed an interesting feature of an exposition staged recently at Poznan, Poland, suggests how dwellings of the future may appear if men eventually live in glass houses. Apart from a few posts and beams, the structure is almost entirely of glass.
PLEASE arrest me” is, in effect, the message conveyed by a new German invention designed to aid the police in capturing “hit-and-run” automobile drivers. The moment a car hits a person or another vehicle, the device, located under the chassis, is said to raise a white plate with a winking red light above the license plate, and also automatically to disconnect and lock the speedometer, thus showing the rate of speed at which the car was traveling at the time of the accident.
WITH a new attachment for electric light sockets, one pull on the chain turns on the light and winds a spring mechanism that automatically turns it off again at the end of a few minutes. The device was designed to eliminate the needless waste of current in cellars, storerooms, and other places where lights are often left burning for hours after they are no longer required.
THROUGH the magic of modern chemistry, oil field brine, the waste water which collects near the wells, now is salvaged for use. By a process discovered by Dr. Otto V. Martin, Oklahoma City chemical engineer, valuable by-products are extracted from the brine, including magnesium, used in flashlight powders and fireworks; bromine, used in the manufacture of dyes, medicines, and as a disinfectant; iodine, used in medicines, dyes and in photography; calcium chloride, a drying agent; and others.
AN IMPROVED metal stamp fits into the vest pocket and prints any one of twelve characters. A small wheel set in a steel handle has a fraction line, an X-mark, a cipher, and figures from one to nine embossed on its edge. In using the device, the wheel is turned until the character desired is at the bottom.
LARGE enough to keep twenty men afloat, yet capable of being packed in a two-by-three-foot space, a new life-saving “raft” was recently tested in the Hudson River at New York City before members of the United States Steamboat Inspection Service.
PILLOWS, photographs, vases, and wall hangings as loudspeakers are the latest thing in radio, developed by E. L. Rice, Washington, D. C., inventor, who has been experimenting to do away with old-style loudspeakers. Rice’s ingenious reproducers, which harmonize with other room furnishings and decorations, have been made possible by a new type of loudspeaker unit.
A NEW lighting system designed to give shadowless illumination for surgical work of all kinds has been invented by Dr. Leon Lazar, a New York dental surgeon. It has been tested and approved by the United States Navy Department at Washington, D C., and has been adopted by several hospitals and many dentists in New York City.
THOUSANDS of dollars may be lost by American business men each year because their desk tops and those of their employees are covered with glass, the glitter of which causes eyestrain, resulting in mistakes that prove costly. This theory was advanced by Dr. E. E. Free, of New York University (Contributing Editor of POPULAR SCIENCE MONTHLY) in a recent lecture given before a group of illuminating engineers at the Westinghouse Lighting Institute, New York City.
FITTING into a case so minute that even when fully open it can lie comfortably on the palm of the hand, what is believed to be the world’s smallest revolver that will actually shoot is only about two inches long. Some forty years ago this tiny curio and a companion piece were sent over to the United States from England.
FREQUENT breaks in African telegraph wires are caused by giraffes running into them, according to a recently returned big-game hunter. The height attained by many giraffes places the wires well within their reach; the tallest specimen ever shot measured nineteen feet.
RADIO broadcasting has been cleared by Joseph Sanson, French meteorologist and engineer, of the often-heard charge of causing disturbances in the weather. In an exhaustive study of records covering French weather during the last two hundred years, Sanson found that the same atmospheric irregularities that prevail today puzzled the citizens of France long before the Revolution.
WHETHER a person is destined to be fat or thin may be determined for him from birth, according to the researches of two German physiologists, Professors W. Grunthal and E. Grafe, of Rostock University. They conclude that an infinitesimal button at the base of the brain probably controls one’s “basal metabolism,” which is really the rate at which an individual expends energy.
A MAN who writes “ton” when he means “not,” and “bat” for “tab,” may be “left-eyed,” according to Dr. W. F. Dearborn, a psychologist of Harvard University. This is the optical consequence of a natural tendency to be left-handed, he said, and may be expressed in “mirrored ” reading or writing.
THE fine points of deep-sea fishing, instead of history or the three “R’s,” are taught at a school recently established in England. The class meets around a large table, pictured above, the top of which represents a channel and harbor. Toy vessels are navigated among miniature sandbars and past incoming steamers by both the instructor and the students.
CHEERILY smiling away any possible omens of bad luck that such a beginning might suggest, a resident of Kingston, near London, England, took his bride off on their honeymoon in a curious-shaped three-wheeled vehicle combining in its construction the features of a motorcycle and roadster.
BOX-OFFICE crushes a few minutes before the curtain’s rise and the delusions of patrons who think that the ticket agent is “holding out on them” and keeping choice seats for his friends, are two of the nuisances of the average theater lobby that may be eliminated if an automatic ticket selling device recently installed at Symphony Hall, Boston, Mass., is generally adopted.
A NOVEL auto jack device that so lifts a car into the air as to remove the necessity for mechanics working under the machine in a pit has been invented by C. Emil Liedberg, of Chicago, Illinois. Driven on steel runways, the automobile can be lifted at the forward end through a screw mechanism operated by hand cranks.
THAT familiar bugbear of surgical patients, taking an anesthetic, may be eliminated in the near future. Dr. J. S. Lundy, of the Mayo Clinic, Rochester, Minn., and Dr. I. M. Isenberger, of the University of Kansas, have collaborated in producing a new anesthetic called “isoamylethyl barbituric acid,” which is said to give fewer unpleasant after effects and incur far less danger than many of the local anesthetics now in use.
BY RUNNING an electrical current through “wild gas,” the gas which escapes from oil wells, Professor S. C. Lind and Dr. George Glockler, University of Minnesota chemists, recently produced a substitute motor fuel. The gas was made to flow through a glass container provided with an inner tube which conducts electricity.
AN EXTRACT made from dried hogstomach was found by recent experiments at the University of Michigan to be more effective in fighting anemia than liver, used successfully for this purpose during the last few years. The new preparation, said to resemble sawdust and to be tasteless, is so highly concentrated that only an ounce a day will prevent a patient’s relapse.
GREATLY increased speed for railway trains, with smoother and more comfortable riding, is the goal sought by engineers of a newly installed concrete roadbed project at Beech, near Detroit, Mich. The rigidity of the new construction is said to prevent sagging of the rails under the wheels of passing trains, thus offering sixteen percent less tractive resistance than the broken stone wooden tie roadbed in common use for the past seventyfive years.
SOME years ago an Englishman, Thomas Griffiths, painted his gatepost white with “a new pigment having a zinc basis.” Immediately thereafter the post began to behave peculiarly. Shortly after sunrise the post turned black, but as night fell it became white again.
A NEW Chinese alphabet was the recent proposal of Loh Seng Tsai, of China, who would create it by the direct application of psychology. He would break up the old-style Chinese characters into “letters” of one or two strokes each. After finding which were quickest to write, and most legible, he would assign new phonetic sounds to them and recombine them into new word-characters.
SWIFTER than a horse” is a phrase that is literally true of the Zuni Indians of the American West, who are often able to outdistance ponies on a long stretch. Their greatest rivals in this respect are the Tarahumare Indians of Mexico, who can outstrip deer in the chase and some of whom have been known to run as far as 170 miles without stopping.
ADJUSTMENT of tappets on overhead valves is made a quick and easy process, it is said, by means of a new tool specially manufactured for this purpose in Cleveland, Ohio. The tool consists of a socket wrench and a screw driver, the latter being inserted through the hollow stem of the socket.
REACHING out like a colossal guiding hand, a huge curved spring girder grasps the bows of great ocean liners entering the new Tilbury docks, near London, England, and pulls them into the berth, where hydraulic bilge blocks rise from the bottom and grip their keels.
TWISTING or bending instead of breaking off when it comes into contact with a curb or other obstruction, a new flexible rubber tail lamp for motor trucks is designed to save repair bills and to avoid court summonses for defective lighting gear, according to its maker.
THE motorman of a new type of trolley car recently put into operation in Albany, N. Y., may sit back in a comfortable seat, fold his arms, and let his feet control the car. Like an automobile, this new street car is equipped with foot controls—a controller pedal corresponding to an auto accelerator pedal, reverser, brake pedal, and emergency brake foot plate.
AN ATTEMPT to come in close contact with the gorilla in its native haunts will be made by Dr. Harold C. Bingham in an expedition sponsored by the Institute of Psychology at Yale University. Accompanied by his wife, Dr. Bingham plans to spend the greater part of a year in the Belgian Congo seeking answers to the many mysteries concerning the mental capacity and habits of the largest of the manlike apes.
COMPLAINTS against noise are probably as old as is noise itself. From time to time, as at present, such protests organize themselves into a concerted attack on the universal menace. In New York City, and in London, England, doctors, psychologists, industrial experts, and others have organized to investigate the harmful effects of noise with a view to striking at the roots of the nuisance.
SAVED from the extinction which threatens their dwindling herd, four elephant seals, the only ones of their kind in captivity, were carried to the San Diego zoological garden a few weeks ago from the Mexican island of Guadalupe, 250 miles to the south.
A FLYING school where not one heavier-than-air machine is to be found is being operated at the Wingfoot Lake Air Station, Akron, Ohio. It is a training institution for commercial dirigible pilots, and is said to be the only one of its kind in the United States.
Handy Voltage-Measuring Instrument Can Be Mounted in a Cigar Box—Short Cuts for Trouble Shooting
THE radio experimenter almost always is handicapped by a lack of measuring instruments. As a result he frequently spends hours looking for trouble that could be quickly spotted by the aid of an accurate electrical measuring instrument.
THE potentiometer used in various ways in receiving circuits is simply a resistance with a sliding contact. The value of this resistance may range from less than five ohms to half a million ohms. The theory of the operation of the potentiometer is simple.
OF THE possible radio troubles which may stop reception entirely, only a few occur with any degree of frequency. Therefore, when the set goes dead, it is well to check first the points where trouble is most likely to be found. For example, since a burned-out tube is perhaps the most common trouble with full electric sets, look first to make sure that all tubes are working.
Easy to Assemble, They Range from Screen Grid Receivers to Short Wave Adapters
ALFRED P. LANE
BUILDING a radio receiver from a complete kit of parts offers fascinating possibilities to the man who likes to build things himself. And because the component parts are completely finished and all mechanical work is done, the assembling of a set from a modern kit will appeal particularly to the man who hesitates to tackle a job involving laying out, drilling, sawing, filing, and so on.
Household Service from Light and Power Appliances Increases with the Number of Circuits and Outlets
ROGER B. WHITMAN
When Edison invented the electric lamp fifty years ago, and ask people to run wires into their houses for light, it is hardly possible that even in his wildest dreams he guessed that within a half-century those same wires would be serving at least sixty-six other household purposes, ranging from opening doors to curing disease, and from cleaning rugs to warming the baby’s bottle.
A Woman Driver Learns from Gus a Few Simple Rules for Turning and Backing without Hitting the Curb—or Worse
"WATCH out” Joe Clark called warningly to his partner, Gus Wilson. “Here comes Mrs. Sedgwick trundling her combination rolling nursery and dog kennel.” Gus looked up from his work just in time to see Mrs. Sedgwick cut in to the Model Garage gasoline pump so closely that the rear wheel bounced over the curbing.
How to Construct a Small Cockpit with Controls That Operate a Miniature Plane
CHARLES A. KING
EVERY boy has at some time imagined himself seated at the controls of a speeding pursuit plane, conscious only of the drone of the motor, the whir of the “prop,” and the hum of the strut wires. He banks the plane, goes into a gradual groundward glide, and levels the plane off just enough to bring the ship down in a three-point landing.
IN THE old Colonial days, no American home was considered properly and completely furnished without a graceful console or card table for the hall. Above this table was probably hung a Chippendale mirror (such as was illustrated in P. S. M., Nov. ’29, p. 88).
THE Christmas village or garden illustrated, with its starry sky, realistic mountains, and folding platform and foundation, is simple in construction. It can be modified from year to year and there is no sawdust or sand to cause the housewife grief.
A Prize of $10 Is Awarded Each Month for the Best Idea or Suggestion of Practical Value to Motorists
CARRYING water in a hat, shoe, or even in the bowl of a headlight are possible methods whereby water can be, put into the radiator in an emergency. But it is much more satisfactory to do the job by the ingenious method shown in Figure 1. The device consists of a three-foot piece of discarded inner tube.
A SHORT in the high tension wires leading to the spark plugs, caused by moisture, usually occurs where the wires are clustered together. When this happens, dry the wires, one at a time, as in Figure 2, with a cloth on which is placed a generous amount of either soapstone powder or face powder, preferably soapstone.
THE enamel on the auto radiator and cowl frequently is scratched by raising and lowering the hood carelessly. Such scratches can be prevented by attaching small leather "fenders” to the corners of the hood, as shown in Figure 3. They are made from sheet leather about two inches square, folded over as indicated, and riveted to the corners of the hood.
A WOODEN block and two ordinary nails can be fashioned into the handy spark plug tester shown in Figure 4. It is the idea of Carl Rutledge of Wauna, Ore., and wins this month’s prize of $10. First bore the hole as indicated, and then drive two nails through diagonally so that their points will approach within an eighth of an inch of each other.
THE indicator illustrated in Figure 5 gives definite warning when the water level in the radiator gets too low. This diagram shows only the principle of the device for the contact must be arranged to suit different radiator caps. A cork float on the end of a rod should be used and a short length of copper or brass tubing should be soldered in place against the hole in the radiator cap to act as a guide and keep the float rod in a vertical position.
Oiling Electric Locomotives—Type of Lubricant to Use and How to Apply It—Keeping Tracks and Switches Clean
FREDERICK D. RYDER
THE importance of the proper lubrication of fast moving machinery has been dinned into everybody’s ears so frequently that it seems unnecessary to repeat the advice as applied to model electric railways. Bearing pressures are relatively light, bearing speeds at some points are quite high, and the lubricant that cuts friction to the minimum under such conditions is a very light, high-grade machine oil such as would be suitable for typewriters, sewing machines, and other similar light machinery.
CHIP carving, although the easiest form of wood carving, is also one of the most decorative. Many people associate chip carving with small triangular cuts and do not realize that beautiful sweeping curved cuts and embellishments can also be made.
MANY small shop operations can be accomplished with greater ease if the worker knows how to make the best use of familiar, everyday materials. Who would believe, for instance, that such things as sealing wax, cement, and paraffin have a place in the average shop.
GRINDING copper, as most machinists know, is one of the jobs that cause much consternation and worry about the shop. It can be done, however, with little preparation, trouble, or expense by the application of a simple shop kink. Because of its quality of softness, copper when ground on an emery wheel tends to clog the pores of the abrasive and thus impede the cutting efficiency of the emery.
FOR some time we had difficulty in finding bolts for the adjustment of the lift valves on a Diesel engine that would stand up under the continual hammer to which such pieces are subjected. After trying every stock and factory bolt available, we decided to use ordinary wrought iron bolts, casehardened at the end subjected to the impact.
IF IT is necessary to build up a portion of a forming die with a welding torch, use chips of the same steel for the filling material. You can make an emergency follow rest by clamping a straight-tailed dog to the tool post. A brass block is used under the dog screw to run on the work.
LIKE all fore-and-afters, the Bluenose gets much of its beauty from its rigging and sails. Everyone enjoys the magnificent sight of a sailing schooner with its sails up and bellied in the wind. Sails always give a sense of action and a note of life, and because of this much of the success of the model depends on the care with which the sails are cut and rigged.
MANY of us exercise meticulous care in the sharpening of our shop tools hut forget about the axe that we use to chop our kindling. An axe, like all other cutting tools, will do its allotted job quicker, with more accuracy, and with less physical exertion on the part of the user if its edge is in perfect condition.
FOR cutting cylindrical glass, as when removing the tops and bottoms of glass bottles or dividing glass tubing, the method to be described will be found efficient and successful. Build a wooden frame as shown and hang it overhead in such a position that it will be near an electric light socket.
AN EASY and effective trick is to letter a prophecy on the shell of an egg, using a mixture of an ounce of alum in a half pint of vinegar as the medium and applying it with a fine brush. Place the egg in water and boil for about fifteen minutes. The lettering on the shell will disappear, but on removing the shell, the prophecy will be seen on the hard-boiled white of the egg.
THE bud vase and nut bowl illustrated, aside from being attractive ornaments in any home, have the added value of being good object lessons in the art of using wood-turning tools for the owner of a motorized home workshop. They also make ideal projects for the school woodworking shop, especially in the use of the faceplate.
TO ASSIST you in your home workshop, POPULAR SCIENCE MONTHLY offers large blueprints containing working drawings of a number of well-tested projects. Each subject can be obtained for 25 cents with the exception of certain designs that require two or three sheets of blueprints and are accordingly 50 or 75 cents as noted below.
BOOK ends as shown are both decorative and durable and when completed will make a gift that is practical for any occasion or will be a valuable addition to the reader’s own reading table. They are made by a new and easy method of embossing. First, decide on the size and shape desired.
EXCESSIVE line voltage, which often burns out Christmas tree lights, can be reduced by the interposition of a resistance in the circuit. There are two ways of accomplishing this. One is to place a wire resistance in series with the bulb line. The other way is to attach another bulb socket to each set of lamps, making nine in series instead of eight.
EVERY home worker is likely to be confronted at some time or other with the task of fitting a standing door fastening. There are many different fastenings on the market, but of the large variety, the ones here described are among the most common and most efficient.
FOR those who enjoy working with tools but are cramped for room, this folding workbench should solve the problem. Opened, it provides ample space for large work; closed, it rests against the wall, out of the way and practically out of sight.
SWUNG open in a violent gust of wind, this garage door was badly damaged. The top rail broke away from the outer stile, two of the wood muntins between the panes of glass fell out, and the center rail pulled away from the hinge stile. The garage builder, asked to supply another door, could not do so because one with six lights was required, whereas he was then using only doors with eight lights.
TO MAKE this 40-in. long model of H.M.S. Queen Elizabeth, Gerald S. Rees, of Nelson, British Columbia, spent 700 hours of his spare time. Materials were obtained for the most part from five-and-ten-cent stores; the cost accordingly was negligible.
THE attractive chest illustrated holds about one hundred cigarettes. It also can be used as a jewel box if desired. Its construction is simple and the materials inexpensive, and with Christmas in the offing it presents a fine idea for a gift.
HOME workshops vary in many ways. Some are unique because of their low cost; some are outstanding for their completeness; each has some feature a little bit different from the others. That is to be expected, since some amateur craftsmen enjoy small work, others large work, and still others prefer unusual types of artistic metal or woodwork.
A TWISTER for forming model airplane propellers from thin balsa blanks can be made from a few pieces of scrap wood and a small length of broom handle. Twisting propellers with this device eliminates bothersome carving. If the broom handle fits into the holes firmly, wing screws will not be necessary.
SHAFT straighteners are useful for the machinist who is working with stock of small diameter. A powerful type of straightener is that illustrated. The parts are hand-forged machine steel. The horizontal bar has a trunion on each end for supporting the hooks and a hub in the center which is bored and threaded to receive the screw.
THIS easily constructed sled is a small copy of an actual Northern dog sled. Make two shoes A and top-rails B of white ash, though heavier wood will do if ash is not available. Soak these in boiling water for an hour or so. Lay out the curves on a long board and drive nails or place fitting blocks to hold the stock in shape while drying.
HARD-SURFACED steps are always a source of danger during the icy winter months. The wooden storm steps illustrated not only give a surer grip but supply a handrail for added safety. They can be set up and taken down easily, and can be stored compactly during the warm months.
ONE of the best ways of making plaster casts of medals, figures, or ornamental objects is to prepare the molds in wax. A special wax for taking impressions is a mixture of 4 oz. of beeswax and 1 oz. of olive oil, melted together. To this is added 4 oz. of sifted starch, which is worked into the liquid until the whole takes on a doughlike consistency.
You Can Set the Hull on Posts or Miniature Launching Ways, or Even Give It the Appearance of Being Afloat
E. ARMITAGE McCANN
FOR the ship models we have made together through the medium of POPULAR SCIENCE MONTHLY, I have in all but one instance suggested bases or stands consisting of two uprights that grip the keel and more or less embrace the hull, with a horizontal board or stick to hold them apart.
IN THE absence of a vernier height gage for scribing lines accurately or in the event that such a gage cannot be used, dividers may be set very precisely with micrometers. To aid in setting the micrometers, two caps are made to fit on the end of the spindle and on the anvil as shown.
What should be done when a door sticks? GENERALLY, a well-hung door in a well-built, well-seasoned house will cause little trouble; but when the furnace heat is on in winter and during the heat and humidity of summer, the best of them are likely to forget their manners.
BECAUSE ash cans are heavy and awkward to handle, and rolling them on the concrete walk bends the bottoms, I made a truck as shown below. If desired, more crossbars can be added. The hooks are fastened to the handles of the ash barrel. To unload, all that is necessary is to let the barrel down, for the hooks will slide OFF.
BY SMOOTHING coconut shells with a file and sandpaper, they can be brought to a finish similar to that possible on hardwood. The attractive ash tray, book ends, loving cup, candle lamp, and electric lamp illustrated were made almost entirely of coconut shells finished in this manner.
BY BORING several holes towards the front of the top step of your stepladder and adding a clip or two on the back edge as shown, it is possible to make a convenient rack for tools. When one is working on a stepladder, such a rack will be found very convenient, for merely laying the tools on the top step often results in a trip down the ladder to retrieve something that has fallen to the floor.
THE miniature bowling alley illustrated is easily built and when completed provides means for playing an interesting game. Clear, select pine is the wood most suited, but any available wood will serve the purpose. The board for the alley is brought to size first, and then the holes are laid out on the sides of an equilateral triangle, as shown.
Soft Soldering Art Metal Work by Direct Heat Method
MANY fine pieces of decorative metal work have been ruined in the last stages of construction by the inability of the worker to do good soldering. Of the many solders used in art metal work, soft solder is probably the most serviceable and the easiest to handle.
WHILE the table lamp illustrated possesses distinction and grace, it is so simply designed and made of such easily obtainable materials that the handy home craftsman can proceed in its construction with celerity and precision.
AS EITHER an individual or a school shop project, the andirons illustrated should prove interesting. Almost every home, even apartments, are now being built with at least one and sometimes two open fireplaces, which must be supplied with andirons.
THE ancient Chinese, credited with the invention of the earliest printing press, paper and gunpowder, also enjoyed a primitive form of “talkies” more than 2,000 years ago. Investigators of the Field Museum of Natural History in Chicago have found that the shadow play, really a forerunner of the American conversational movies, which is still popular in China, was first mentioned in historical documents dating from 121 B.C.
1. There is no one “best” type of heating system. Each has peculiarities that make it suitable for use where these peculiarities are advantageous. Hot water heat, for example, is excellent where uniform temperature with the minimum of attention to drafts and so on is required.
AN AIRPLANE hunt for bacteria was a recent novelty at Cambridge, England. Its object was to determine how plant and crop diseases are spread in upper air currents. Several kinds of germ traps were used by the airplane that made the tests. Glass slides smeared with petrolatum, and test tubes and glass dishes filled with jellies offering breeding places for germs, were exposed at certain times during the flights, which reached a maximum altitude of 13,000 feet.
V-SHAPED wings and the absence of any tail whatever are novelties combined in the latest German plane tested recently at Berlin. It demonstrates, as did the “windmill” autogiro plane, that radical ideas may still have a place in airplane design.
BOARDING a flying plane by a sixty-fivefoot rope ladder and leaving via parachute was the unusual performance of Dale Dryer, airplane mechanic, when an endurance plane over Buffalo, N. Y., sent a call for repairs. Heavy weather had damaged the stabilizer of the airplane, which had been aloft more than 190 hours.
ANY amateur scientist desirous of testing for himself the effects of sun spots on tree growth, on human wars, or on anything else, down to the rate at which a farmer’s hens lay eggs, now has conveniently at hand the material for such studies.
THE Royal Dutch liner Batavier V, carrying on her bridge three lighted arrows which indicate to approaching vessels the direction of her course, is the subject of an experiment which may lead to the displacement of sound signals as a means of mutual warning between ships on the high seas.