Can Science feed you and me? Can chemistry supplant Nature’s intricate processes of growing life, making us independent of crop failure and banishing forever the fear of hunger and famine? In POPULAR SCIENCE MONTHLY next month Ellwood Hendrick, Sc.D., nationally famous chemist and author, will tell you what our chemical laboratories are doing to solve the world food problem.
AN OPEN-END wrench that sells for 10 cents looks the same as a wrench that sells for 30 cents. But looks are only “skin deep.” It is what is under the finish that determines whether a wrench, or any other tool, will stand up under the wear and tear of everyday use.
A FEW weeks ago I had the thrilling experience of visiting a modern house of wonders where science plays the host. This house of wonders is a stately building of creamy marble, picturesquely situated near the banks of the Potomac at Washington, D. C.
THERE has been much talk recently of super-power. Eminent engineers have estimated that 80,000,000 horsepower in electrical energy could be produced by utilizing fully the water resources of the country; energy equivalent to that contained in 800,000,000 tons of coal, or 200,000,000 more tons than the total annual product of the mines of the United States.
IN THE Pacific Ocean, about 500 miles off the coast of Ecuador on the equator, lies a tiny group of desert volcanic islands known as the Galápagos Archipelago—dots of barren lava land that still live in the Age of Reptiles! Here, among outlandish creatures that never have heard the voice of man, the dominant sound of life is the hiss of the sea iguana—a giant marine lizard that exists nowhere else in the world.
A Dramatic Story of Applied Science at Three Miles a Minute
A LITTLE more than 30 years ago one of the many blue-eyed lads in the ancient Norse town of Trondhjem, about halfway up Norway’s long Atlantic coastline, yearned boyishly for a luxury that few men hoped to enjoy at the time. The lad dreamed of owning a bicycle.
MOST of us have heard stories of the father and mother who have lived together for 40 years and who, one evening as they sit under the reading-lamp, engage in the following conversation: “Wonder if John won’t come home this Christmas and bring Mary with him,” remarks the father.
Dramatic Possibilities that Lie in the “Mystery Ray"
Frederic Mortimer Delano
STORIES of mysterious rays capable of stopping automobiles, bringing down flying airplanes, killing men and other destruction have come from many parts of the world in the last few months. A dozen or more inventors have announced the discovery of means for transmitting electrical energy in any direction without the use of intermediate transmission wires.
I WONDER if you realize how much effect the weather exerts on your daily life and activities? How much less work do you think you can do on the hot days that are more or less seasonable now than you could on pleasant days last spring? To what extent do you think your ability to concentrate has been affected by the heat?
HAVE you seen a spider’s web, glistening with dew in the dawn? Nature offers no more charming sight, for the dewdrops reveal the marvelous structure and beauty of the spinning The threads of the web are of silk, 100 times finer than hair, yet stronger than steel, and consequently capable of enmeshing even large insects upon which the spider bandit satisfies its appetite
THE helicopter, one of the earliest forms of heavier-than-air machines, but neglected during the years when the airplane was being developed, recently has come into considerable prominence, and its “renaissance” has resulted in comment that is of a widely divergent sort.
Keep in Step with Useful New Discoveries and Inventions
A King of Locomotives
Photographing the Invisible
An Aid to Super-Power
Around the World in 17 Days
Bricks Made from Dirt
FOR years the telegraph has apprised us of the news of the world almost as the events have occurred. Now it also can show us pictures of far-off happenings with a speed little less than that required to transmit an account of them, for engineers of the American Telephone and Telegraph Company have perfected a simple, commercially practical method of sending photographs by wire.
A DEVICE that, it is claimed, makes every ordinary door lock burglarproof, consists simply of a small metal tongue to which is attached a small chain, pin, and screweye. In use, the screweye is inserted in the door near the lock and remains there permanently.
TO RELIEVE congested parking conditions, a skyscraper garage, the first of its kind, is being planned for Chicago, Ill. It is designed to park between 600 and 700 automobiles and to carry the cars, without the aid of attendants, from the ground to the upper floors.
A PRACTICAL telephone device consists of a holder for the receiver when in use, allowing freedom of both hands while telephoning, and a handy pad holder supplied with a clip so that papers of various sizes may be used. open, the rear of the elevator floor is raised and the car is rolled into its stall by force of gravity.
THE definition of man as a tool-using animal may have to be revised. Dr. George C. Wheeler and Esther Hall Wheeler, of Syracuse University, recently reported having seen a wasp using a pebble for tamping down the entrance to her burrow. The incident happened in Texas, where the observers were studying insect life.
FOUNDATIONS of steel tubing filled with concrete that, it is claimed, may be laid at a saving of time and cost over the usual concrete piers employed in building operations, have been devised by a firm of New York engineers. By the new method, tubular steel shells from 12¾ to 16 inches in diameter and from ⅜ to ½ inch in thickness are driven down to bed rock.
WORK on the greatest irrigation project in history, the plan of which is shown above, was begun recently by British engineers. It provides for regulating the flow of waters of the Indus River in India, to irrigate by seven great canals and tributaries the arid plains of Sind, including 6,000,000 acres of land now largely desert.
ABSOLUTE protection for the automobile and everything in it now is promised by a “metal policeman” that sounds the horn as a warning signal as long as the car is molested. The burglar device, designed also to protect garages, barns, and similar buildings, is an electric alarm with a secret switch.
Model “Health Street” Demonstrates Child Hygiene Work
TO DEMONSTRATE the importance of child hygiene education in the home, the Department of Health, Newark, N. J., recently prepared a model street for a public health exhibition. All of the buildings were fitted with swinging fronts which, when opened, presented an interior of the rooms in each building, revealing the various types of educational health work carried on in the home by the bureau.
EVEN the army fighting tank now has radio ears and a radio voice. This doughty perambulating fort now can be directed accurately from behind the lines throughout a battle, a fact that the designers believe would increase its destructive power enormously in time of war.
TO ASSIST a New York charity fair, a “strong woman” vaudeville performer stopped the crowds at Times Square recently by lifting an elephant. The animal stood on a specially constructed platform, suspended by chains from straps slung over the performer’s shoulders.
IN THESE days of dancing, whistling, and fiddling champions, there now appears William J. Murphy, of Massachusetts, who claims to be the champion barrel maker in the United States. He holds a record of making 120 barrels a day for 44 days straight, a total of 5280 barrels in all.
THE bobbed-haired miss with henna-hued curls is not an exclusively modern product. On the Samoan Islands, native men wear their hair long. The women, however, cut theirs short and bleach it an auburn tint with a wash that is compounded from the leaves of a wild plant.
Odd Motor Caravan on the Riviera Carries Its Own Canoe
THE latest style for a sight-seeing trip on the Riviera is by motor caravan. Vacationists at Cannes, France, recently were startled by the sight of a diminutive car not much longer than the canoe it carried on its odd top, drawing a very large hooded trailer that served as a covered home on wheels.
A HUGE natural garage in the hollow of a great baobab tree, was discovered recently by a motorist in Nyassaland, Africa, shortly before nightfall. His car, a Ford, was accommodated handily by the high sheltered space. Despite its great hollow, the tree was alive.
WITHIN the earth is a large wave that moves around the planet once every 8800 years, according to Ludovic MacLellan Mann, a member of the British Royal Anthropological Society. He says the wave moves the position of the earth’s axis and poles slightly, resulting in climatic changes.
ONE of the world’s largest coast defense guns, recently shipped to New England, is shown below. The 16-inch weapon weighs 210 tons. A specially constructed car was necessary for transportation and 50 men to move it.
THE world’s smallest and largest incandescent lamps—one rated at about one quarter candlepower and the other at 100,000 candlepower—recently were exhibited by the General Electric Company. The large lamp, with a bulb 12 inches in diameter and 18½ inches high, was developed for motion-picture studios.
SLOTTED cardboard disks inserted behind the tuning dials of your set so that a portion of each disk is exposed to view, can be made to serve as a handy index for quickly tuning in any desired station, without the usual adjustments over a wide range.
A NEW type of grid leak differing from other types in the fact that it uses a liquid for its high resistance element, recently has been developed to eliminate microphonic noises. The new instrument is composed of a glass tube one-half inch in diameter and five-eighths of an inch long, about one-third full of liquid.
IN THE U. S. Navy’s “radio central” station at Washington, D. C., has been perfected a teletype system by which an operator, simply by “typing” messages on a lettered keyboard, can transmit navy communications by radio from Washington to San Diego, Calif.
IN AN attempt to obtain perfect selectivity, an inventor of Brooklyn, N. Y., has perfected an unusual combination horizontal-vertical loop aerial to be used with sensitive receiving sets. Tuning of the aerial is accomplished by turning the dial shown in the photograph below.
WILL plant life ultimately be affected by the ever increasing radio activity and the constant disturbance of the ether? This question recently has been put to scientists of the Smithsonian Institution and the U. S. Department of Agriculture. While they are not ready to offer a definite prediction, they point out that some, if not all plants are sensible to ether conditions and that these plants may be listening in, just as are hundreds of thousands of human beings all over the world.
CERTAIN American stations are heard with crystal sets throughout the British Isles, the programs being received and amplified by this new 13-tube set, at Biggin Hill, Kent, England. Programs on a 100-meter wave length, too low for most American amateurs, are caught by this station and relayed from nine broadcasting stations, each with a different wave length.
THE map below illustrates how, in 5/100 of a second, a radio signal recently streaked around an 8500-mile circuit; from New Brunswick, N. J., to Warsaw, Poland, and back to New York. The round trip of the test signal was timed by a motion-picture camera actuated by a set tuned to the receiving station at Riverhead, L. I. This camera was in Washington, D. C., at a club where the observers were gathered.
DIFFERING from the standard types of radio cabinets, this new six-tube set has a glass door at the top, through which the tubes are visible. This door may be opened to allow easy access to the rheostats placed between the tubes within. Two tuning dials are on the panel below.
WHERE several persons wish to listen in with separate headphones instead of a loudspeaker, some means must be provided to connect the various phones in series. This manner of connecting cuts down the volume on each phone. When only one or two persons wish to listen, therefore, it is advisable to take from the circuit the phones not in use, thereby increasing the signal strength in the phones in use.
TESTING radio A batteries with an ammeter is not a satisfactory method of determining the best brand, according to George W. Vinal, chief of the battery section of the United States Bureau of Standards. Mr. Vinal explains that some of the very best and longest lived batteries do not give as high an ammeter indication in this test as inferior brands.
Mysterious Fire in Paved Roadway Has Been Burning a Year
FOURTEEN years after a creek bed in Philadelphia, Pa., had been converted into a paved street, a passing autoist noticed a slender curl of smoke rising from a slight crevice in the roadway, thus discovering a fire that probably will shatter all records for novelty and length of activity before it is finally subdued.
TO SOLVE the problem of building a 90-foot dam in the Columbia River without blocking the run of salmon that go up the river to spawn, model escalators will be erected to determine whether the fishes will consent to this form of transportation.
A SIMPLE wooden gage has been devised to determine whether your car has sufficient clearance for use of balloon tires. The gage consists simply of a stick with holes at certain distances from one end. These distances correspond to what may be termed the radius of the clearance circle.
ITNSTEAD of dismantling a 22-ton excavating shovel in order to lower it from cliffs down to a dam at Eau Claire, Wis., engineers saved a week of time and expense by running the machine into the Chippewa River about a quarter of a mile below the dam and then moving it upstream under its own power.
Airplanes Paint the Sky with Writing of Many Colors
THE three planes shown above are painting the sky with colored writing over Hazelhurst Field, L. I. Traveling at a speed of 135 miles an hour, a camera man in another plane snapped this unusual picture. The new method of painting the heavens with all the colors of the rainbow is the invention of Major Jack Savage.
A COLLAPSIBLE rule designed to take inside measurements accurately consists of eight-inch sections, on the edges of which are grooves and runners that permit it to be pulled out for a short distance or to its full length of three feet. A spring catch holds each section when it is pulled out to the full.
IT LONG has been known that the mosquito is the only active carrier of malaria. Only one mosquito in 1000, though, carries the malaria parasite in an infectious stage, scientists of the Johns Hopkins School of Hygiene discovered in a recent investigation in Louisiana.
THE Great Lakes rapidly are becoming major highways for transportation of automobiles. Manufacturers are beginning to load large freight steamships with hundreds of cars at Detroit for shipment to distributing points along the lakes instead of driving them overland or shipping them by rail.
ESPECIALLY designed for cutting heavy metals, a new tip for acetylene torches, recently developed, is said to effect a substantial saving of time and fuel by a new process of mixing the gases, preheating the cutting oxygen, and giving added velocity and penetration to the preheating and cutting jets.
MOST of us, some time in our lives, may expect to hear the terrified call for help from a drowning person; yet how many of us would know how to attempt a rescue? Every day in the United States about 20 people meet death by drowning, so the value of general knowledge of life-saving is obvious.
AN AUTOMATIC teaching device, designed to aid children to master fundamental facts and to train them in automatic thought processes such as addition and combinations of numbers, has been developed especially for use in the lower school grades.
COMBINING 14 different instruments in one, a novel one-man guitar, when properly played, is said to produce the effect of a real jazz band. The instruments are played at the same time in order to give the effect of a full orchestra. The “band” was invented by Signor Miguel Juan, of Belgrade, Servia.
A MARVEL of patience and skill is represented in this beautifully carved elephant tusk on which a father and son worked nearly 50 years. The carving was done by Hindus. When the father who started the work died, the son carried it to completion after many more years of work.
AMAZING new uses for the camera as an instrument of scientific research have been found in the last few weeks. At Ohio State University, Professor Wesley G. France has devised a microscopic motion-picture camera capable of photographing the movements of molecules in chemical action.
OFFICIALS and residents of Washington, D. C., no longer need call on a tailor to get their trousers pressed. A telephone call will quickly bring the tailor’s “wagon” buzzing up to the door and complete tailoring equipment within the car will press suits while the owner gets an extra sleep.
THIS folding baby carriage is designed especially for greater convenience on a street car or in an automobile. It folds compactly into what resembles a large walking-stick with two rubber-tired wheels at the tip. Opened for use, it affords the baby a comfortable swing seat.
WITH 44 different kinds of street lights in actual operation, Columbus, Ohio, bids fair to gain national fame as America’s street-lighting laboratory. Several cities have sent delegations there to study the demonstration. THE largest and most imposing model ever used as an exhibit in a trial in the Supreme Court in New York City was recently constructed to portray a section of subway to the jurors hearing the suit for $1,400,000 damages brought against the city by a construction company.
UNDER some conditions aviators are able to brush small clouds out of the sky by flying through them repeatedly. A fair sized summer cumulus or fair-weather cloud sometimes may be obliterated by about 20 flights through it.
A RAILROAD sedan capable of a speed up to 80 miles an hour was constructed by the Southern Railroad Co. by equipping an automobile body with flanged car wheels and a cowcatcher. It was built for use in inspecting tunnels and for emergency wreck patrol duty.
AFTER two years’ work on construction, the Don Pedro dam, near Modesto, Calif., highest impounding dam in the world, has been completed and its waters are being used for the irrigation of 240,000 acres of land formerly useless for cultivation.
A TWIN-MOTORED amphibian airplane capable of taking off or landing on water or land is one of the new type of planes being developed for commercial purposes by the Civil Aviation Department of the British Air Ministry. The plane is designed to carry 12 passengers, a pilot, and an engineer.
TO GIVE special service to patrons desiring to deposit money after banking hours, a Philadelphia bank vault company has invented an ingenious safety deposit chute that leads from the exterior wall of a bank building to the safety vault within.
A RECORD pipe shipment was made recently from Alliance, Ohio, to Orange, Texas, when one section of pipe with an inside diameter of 8 feet occupied five flat cars for shipping. Its total length was 124 feet and 60 men could stand in line along the top.
FOR use in reading-rooms, hotels, libraries, banks, etc., a fountain pen attached by a small chain to a neat-looking cabinet furnishes a first class writing instrument always in working order. The fountain pen is normally held upright on the side of the stand.
A FEW years ago the bison, or American buffalo, of the Western plains, was threatened with extinction. Now, though, this danger is past. Where there were only 1100 head of bison in the United States and Canada 20 years ago, there are about 15,000 today—a fact that is due largely to the efforts of the American Bison Society in stopping the wholesale slaughter of the animals.
FOR traveling the heavy mud roads of New Zealand a concern operating motor stages equipped their cars with special contrivances for towing automobiles out of mud holes under their own power. The device consists of a steel drum containing 500 feet of wire rope with a breaking strain of four tons.
AN UNUSUAL engineering feat was recently accomplished near Pueblo, Colo., when a contractor was forced to assemble and rivet a 100-foot steel bridge on one bank of a stream and then pull it into place because mountain floods had twice washed away all the supports.
MUCH of the pleasure of a summer auto-camping trip or a day’s outing depends on the arrangements you make for comfort and convenience at mealtime on the road. To provide these conveniences in a compact form, a complete dining outfit, including table, chairs, food containers, utensils—everything necessary for the outdoor meal—has been devised to fit into a metal case that will ride on the runningboard of the car.
WHEN steam begins to pour in clouds from the radiator of your car, it is a sure sign of an overheated engine. Such a condition often may result in serious damage, such as burned bearings or frozen pistons. If your engine overheats on the road, it is wise not to take the chance of continued driving.
THE interlocking steel lacing principle already applied to galoshes and tobacco pouches, now is being used for shoes. When such shoes are first bought, the laces are tightened to fit the foot. After that it is necessary merely to slide a key up or down to “lace” or “unlace” the shoe.
CHEMISTS at the University of Washington are experimenting with oleoresin, a fluid found in pockets in the Douglas fir, in an effort to produce a substitute for commercial turpentine now obtained from our rapidly disappearing yellow pine.
A HANDY holder for displaying cut flowers attractively in the yard or greenhouse consists of a wrought-iron rod to which is fastened a wire basket holding a glass vase. The rod, pointed at the lower end, is inserted in the ground. A castiron plate at the surface affords a firm base when the rod is in the ground, and keeps it from tilting sidewise.
TO OPEN collars at the fold so that the tie may be slipped through easily when worn, an instrument known as a “collar cue” has been invented. The collar is inserted on the fork of the cue and pulled through. A tongue spreads the fold.
WHAT is said to be the largest safe in the world has been installed in the new Fourth Federal Reserve Bank at Cleveland, Ohio. The steel vestibule, or frame weighs 200,000 pounds, while the door and the remainder of the gigantic vault weigh 300,000 pounds more.
FIHSHERMEN, hunters, and hikers no longer need to be driven from their pleasures by sudden heavy showers. Emergency raincoats made of crepe paper especially treated will allow the fishing and hunting and hiking to go on without interruption.
FOR stairways where the daily traffic of thousands of people scuff away the toughest of tread materials, necessitating frequent replacements, and where the danger of slipping accidents becomes a grave problem, there recently has been perfected a non-slip safety tile of an abrasive material which is commonly used for grinding.
IT IS surprising how many fascinating facts of science may be found in the most commonplace objects and incidents of every-day life. Are you in the habit of asking questions and finding the reasons for these apparently unimportant things and happenings, or do you just take them for granted?
A BAKER of bread by night, and a breeder of fish by day. Such are the odd titles of Louis Beldt, of St. Louis, Mo., whose vocation takes him to the bake ovens at 3 A. M. each day and whose avocation has resulted in his recognition as an authority on fish culture and in possessing one of the finest privately owned collections of rare and tropical fishes in the country.
A STANDARD-SIZE umbrella designed to fold into a compact bundle 10 inches long and 2½ inches in diameter is to be placed on the market. It is so small that it will fit into the coat pocket or into the smallest suitcase or traveling bag. The metal handle telescopes, the double set of ribs folds toward the handle and the outer section of the cover folds against the inner half.
NEARLY any standard typewriter now may be converted into a noiseless one merely by placing over it a soundproof typewriter cabinet that permits the use of the machine without the usual clatter of keys. The paper and writing are visible through a glass cover.
A SAVING of from $50,000 to $100,000 a day and a big step toward conservation of the hardwood supply of the country recently has been effected by the Ford Motor Company through the discovery of a means for successfully utilizing every part of lumber except the knots, and thus increasing the useful output from each log from 30 to 50 per cent.
BY MEANS of a new device that is attached to the automobile gasoline tank under the front seat, the necessity for the driver to first remove the seat cushion before refilling the tank with gasoline, is eliminated. The apparatus consists of a flat aluminum neck, one end of which is inserted in the gas tank.
A NEW paint-brush handle shaped similarly to the handle on a saw, is said to eliminate strain and cramps usually experienced from the straight type handle, and also to allow a much freer arm and wrist movement in painting. The shape of the handle makes it possible for the hand to hold the brush in a relaxed natural position, thus preventing blisters.
“Horse’s Hoof” and “Shoe Sole” Reproduced in Rocks
THE Darwinian theory of evolution was challenged recently by two alleged fossils, one of a horse’s hoof and one of part of a human shoe sole, when they were exhibited to Eastern scientists by John T. Reid, a mining engineer of Lovelock, Nev.
PLATINUM is even more valuable to the scientific worker than it is to the jeweler because of its power of resisting corrosion. Its cost, though, is so great that it must be used sparingly. Recently, however, science has found an effective and very much cheaper substitute for platinum in certain alloys of chromium and in iron electroplated with chromium.
THE regular winds that sweep over the Sahara Desert create innumerable little ripples on the surface of the sand-dunes, as may be seen in the two upper illustrations. It is interesting to compare these miniature dunes with similar ripples that form in a piece of sheet metal shaped like a dune, swept by the violent rush of hot air from an acetylene flame, as shown in the lower picture.
THE work of taking magnified photographs is simplified by a new type of microphotographic lens that can be attached to any standard hand camera. A small disk at the end of the lens tube holds the object to be enlarged. Ample illumination is secured from an electric-light bulb, and ordinary subjects require only a few seconds’ exposure.
BY AN invention perfected by a French hospital interne, the most delicate operations may be projected and enlarged on a screen in a lecture room some distance from the operating room. The projected picture is said to show every detail of the operation and all the objects in natural color, while the operating surgeon explains his movements to his distant “audience” by means of a loudspeaker.
Loudspeaker and Automatic Call Recorder for the Telephone
TWO remarkable automatic devices, both designed to do away with proverbial inconveniences in telephoning, have been perfected within the last few weeks. One is a “telephone telltale” which, in the absence of its owner, automatically prints on a slip of paper the number of an incoming call.
AN AUTHORITY has said truthfully that if all the waste in the construction of small homes in the United States could be eliminated for two years, the savings thus made would be enough to pay off our national debt! Whenever a prospective home-builder comes to me for advice on how to save money in construction, my first thought is to let that statement speak an effective answer.
A Résumé of Important New Developments and Inventions
Radio without Batteries
Across the Sea
Radio and the Airship
Inventors Are Active
Secrecy Is Promised
A REMARKABLE filament material that is expected to revolutionize vacuum tubes has been discovered in the laboratories of one of the big electrical corporations. It is predicted that this material, when the experimental work is complete, will permit the manufacture of a tube that will practically reach the goal all experimenters have sought to attain—cold electron emission.
HERE is a set that reduces static to a minimum, reduces interference from other stations, and insures improved tuning. It offers distance and volume without the necessity of an outside aerial. It is an excellent set for the crowded districts of the larger cities.
IMAGINE yourself driving along a quiet country highway, serenely enjoying the beauties of nature, when suddenly from a shaded side lane a runaway horse dashes madly into the path of your speeding machine. Will you have the presence of mind to put on the brakes and pull over to one side to avoid a crash, or will you be frozen to inaction for the brief second that will be your time margin of safety, and apply the brakes too late?
A FLAT tire is disagreeable at any time, but a flat balloon tire certainly is worse. One driver may have the endurance to put air into the normal tire, but in pumping up a balloon tire he will have to exert himself to the utmost. The job can be robbed of much of its disagreeable element by the use of the arrangement shown in Fig. 1.
Discarded Furniture Converted into Ornamental Welsh Dresser
Special Table Lightens Labor of Bathing Small Baby
Neat Radio Stand Cheaply Made from Old Bureau
Kenneth M. Swezey
R. W. E
MORE and more, radio is emerging from its purely mechanical chrysalis and is being transformed into a gratifying and beautiful utility. This transformation is being accomplished by the provision of artistic cabinets, by the construction of sets to fit into articles of furniture, and by the use of concealed wiring with numerous outlets throughout the house so that a loudspeaker may be plugged in wherever desired.
AIRPLANE kites can be made in two ways. A plain kite similar to the tailless can have the outline of an airplane, as in Fig. 1, or one may be constructed along the lines of a real plane. The model illustrated in the accompanying photographs is a biplane.
THE chest illustrated was made from the boards of a discarded walnut dining-room table and lined with cedar. To make one like it, lay out and make the sides and ends of the dimensions shown in the accompanying drawing. It is necessary that they should be perfectly square or the box will not be square when assembled.
GAMEY, free-for-all water golf can be played with the homemade outfit illustrated. “Greens” can be moored almost anywhere, and a two-hole course can be played back and forth even on a pond. The waggler, fitted with air tubes under the seat, can be shifted about with pedal-fins, which have power enough to propel slowly.
Graceful Wrought-iron Reading-Lamp for the Amateur Craftsman
Muffling a Punching-Bag Platform in the Cellar
How to Make Concealed Catches for Furniture Doors
H. T. Shrum
ARTISTIC wrought-iron work has been revived to a great extent during the last few years and many decorative pieces are being used in the home. This is evident from the number of iron candlesticks, plant and aquarium stands and reading lamps to be seen in the art and gift shops.
TOOLS are tools,” remarked Old Bill to one of the machine hands, “and it doesn’t make so much difference as you think whether they go in a lathe or planer or milling machine. Cutting metal is the same problem, no matter where you run up against it.
Need for Studying Better Shop Methods Shown in Piston-Ring Contest
Rack Keeps Washers Sorted
ASTONISHING in one respect were the letters submitted in POPULAR SCIENCE MONTHLY’S recent contest on the machining of special interlocking piston rings—no two of the solutions were alike. Every one of the replies varied somewhat in the method suggested for making the rings.
Spindle Button Will Aid in Locating Work Accurately
FILING is an art in which mastery depends mainly upon practice. What a real expert can do with a file is little short of astonishing. There are, however, a few simple directions in regard to filing that no one should overlook. One of these is that a hand file should be used only as a one-way tool.
SOMETIMES it is necessary to produce a circular surface on some part of a job that will not swing on centers. In many cases a job of this kind may be handled on the shaper. In the central illustration on page 76 is shown a typical job of this sort and how it is held in the shaper vise.
Stand Holds “Rough Stuff” and Varnish Rubbing Materials
A Trysquare with Knife Guide
Henry S. Laraby
BENT forms of wire and sheet metal may be produced with a shaper by the use of simple bending dies held in the vise (Fig. 4). The usual way is to cut the wire to the proper length and lay it on the die with one end against the stop. The two guide studs pass through rollers, which reduce the friction.
This Special Woodturning Tool Makes Deep, Smooth Cuts
Screw Heads Slotted Rapidly in Simple Lathe Fixture
A Shock Absorber for an Auto-Towing Cable
Stiff Protectors Shield Freshly Varnished Surfaces from Dust
IN SMALL shops, with the present high cost of rented buildings, it is often a problem to obtain the necessary floor space. All such shops have machines that are used only occasionally. The area occupied by them frequently can be used to advantage for extra bench room.
Blueprints Offer Many Good Ideas to the Home Worker
A FRIEND of mine, the other day, was being entirely too conscientious in the construction of a cabinet. He was working on a pine buffet top, about 20 in. wide, glued up from two boards; and across the under side he had glued and nailed 1 by 2 in. cleats to make what he thought was a very solid and substantial job.
Assembling a Motor Generator Unit for Charging Batteries
Hollow Block Holds Firewood Upright for Splitting
Making Decorative Candle Sconces for Wall Ornaments
Adapting a Two-Man Saw for One Man to Use
Improved Germination Box Gives Seedlings a Vigorous Start
Aerial and Ground Switches Are Useful in Testing Radio Sets
Arthur M. Vinje
FOR charging the storage A battery of my radio set, I assembled the motor-generator unit illustrated. I happened to have the motor, but there is no reason why the motor of a washing machine could not be used, provided it is replaced not later than Sunday evening each week in its proper place on the washing machine.
MEDICAL authorities agree that 65% of all men past middle age (many much younger) are afflicted with a disorder of the prostate gland. Aches in feet, legs and back, frequent nightly risings, sciatic pains, are some of the signs—and now, a member of the American Association for the Advancement of Science has written a remarkably interesting Free Book that tells of other symptoms and just what they mean.
AMECHANIC came to me with a problem the other day. “Mr. Kuns,” he said, “every time I drive this car a few blocks, I get a new knock. I have taken up the bearings a half dozen times, but inside of a mile the engine is knocking again. What is the trouble?
DUFFLE bags and packs often are inconvenient for the camp food supply, so why use them when it is not necessary? The canoeist who does not have to portage can carry a grub box as easily and safely as the auto-camper.
Adjustable Vise Holds Small Articles while Being Soldered
Camper’s Three-Legged Chair Will not Collapse Readily
C. A. Oldroyd
SUSPENDING a loop aerial from the ceiling has several advantages over the usual custom of placing it on the radio cabinet or on a table. It can be swung around more conveniently and accurately and removed in a second without unscrewing any nuts.
Rustic Bungalow Solves Housing Problem for One Family
Joe V. Romig
The inexpensive method of construction outlined in this article is especially suitable for a summer cabin in the woods. BUILT on a plot of ground that had been given up by real estate men as impossible, this rustic bungalow solved temporarily the rent problem of a young mechanic friend of mine.
1. It is the weight of a body compared with the same weight of water. Thus the average specific gravity of rock is 2.77, which means that a cubic foot of average rock weighs just 2.77 as much as a cubic foot of water. 2. The force that starts the shot forward, that is, the force of the explosion, exerts an equal force backward.