Issue: 19310501

Friday, May 1, 1931
MAY 1931
5
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118
Monday, January 12, 2015

Articles
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POPULAR SCIENCE
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PopularScience_19310501_0118_005_0001.xml
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FAYETTE R. PLUMB, Inc.
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FAYETTE R. PLUMB, Inc.
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PopularScience_19310501_0118_005_0002.xml
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1
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CADILLAC MOTOR CAR COMPANY
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CADILLAC MOTOR CAR COMPANY
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PopularScience_19310501_0118_005_0003.xml
tableOfContents
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2,3
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Table of Contents for May, 1931
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PopularScience_19310501_0118_005_0004.xml
masthead
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POPULAR SCIENCE
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PopularScience_19310501_0118_005_0005.xml
article
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4,6,7
Are Bank Stocks A Good Buy NOW?
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Are Bank Stocks A Good Buy NOW?
To Help You Get Ahead
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LEON MEADOW
"SUPPOSE you tell us, Frank—you’re the financier in this crowd. What would you advise a chap with $1,000 to invest his money in these days?” Roger Blake put the question to him as he and John Fallon and Frank Dickinson were waiting one evening at the latter’s house for Ernest Anderson to show up— so that the weekly bridge game could start.
PopularScience_19310501_0118_005_0006.xml
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4
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Cochran & McCluer Co.
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Cochran & McCluer Co.
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PopularScience_19310501_0118_005_0007.xml
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4
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Advertisement: Popular Science
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Popular Science
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PopularScience_19310501_0118_005_0008.xml
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Advertisement
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PopularScience_19310501_0118_005_0009.xml
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Advertisement: POPULAR SCIENCE
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POPULAR SCIENCE
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PopularScience_19310501_0118_005_0010.xml
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5
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THOMPSON BROS. BOAT MFG. CO.
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THOMPSON BROS. BOAT MFG. CO.
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PopularScience_19310501_0118_005_0011.xml
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5
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BRISTOL-MYERS CO.
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BRISTOL-MYERS CO.
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PopularScience_19310501_0118_005_0012.xml
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6
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American Safety Razor Corp.
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American Safety Razor Corp.
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PopularScience_19310501_0118_005_0013.xml
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6
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LARUS & BRO. CO.
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LARUS & BRO. CO.
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PopularScience_19310501_0118_005_0014.xml
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7
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E. I. DU PONT DE NEMOURS & CO., INC.
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E. I. DU PONT DE NEMOURS & CO., INC.
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PopularScience_19310501_0118_005_0015.xml
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8
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Advertisement
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PopularScience_19310501_0118_005_0016.xml
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9
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Chevrolet Motor Company
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Chevrolet Motor Company
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PopularScience_19310501_0118_005_0017.xml
article
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Build for Year-Round Comfort
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Build for Year-Round Comfort
Today's house can be so constructed that change in temperature will not be felt and home can be warm or cool as you wish
INSTITUTE BULLETINS
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F. G. PRYOR
AT SOME time or another, most of us have had the misfortune to live in one of those sieve-like houses that are cold on frigid days, hot on torrid days, and generally receptive to all outdoor changes. Fortunately, however, there are not many houses of this sort going up today, for good building practice now calls for construction that permits temperature control twenty-four hours a day throughout the year.
PopularScience_19310501_0118_005_0018.xml
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11
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BAUSCH & LOMB OPTICAL CO.
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BAUSCH & LOMB OPTICAL CO.
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PopularScience_19310501_0118_005_0019.xml
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11
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Popular Science Publishing Co.
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Popular Science Publishing Co.
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PopularScience_19310501_0118_005_0020.xml
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11
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UNITED STATES TOBACCO CO.
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UNITED STATES TOBACCO CO.
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PopularScience_19310501_0118_005_0021.xml
article
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Our Readers Say
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Our Readers Say
Don’t You Know Chemistry When You See It?
The Electric Belt Makes Radio Debut
Taking the Sting Out of the Kicks
Can You Help Him With His Corks?
Who Are You, And Where, Please?
Here’s an Idea to Save the Patent Office
Submerged Rock Hereby Acquitted
The Artist Insists This Man’s All Wrong
Don’t Let This “Simple” Problem Stop You
Error Started Things In Distant Japan THE diction
They Didn't Really Jump Over the Moon
Did Carbon Monoxide Kill Captain Page?
Carpentry Has No Appeal for Him
Arizona Wants You J. S. of St. Louis
A Well-aimed Knock for Michel Mok
Locomotive Models Are in Demand
Almost Too Lazy to Talk
Where in the World Is the Earth Going?
Bans the Idea of Making Changes
Reader from Fossil Proves He's Not One
Maybe Your Sand Hills Need This Food
This Little Girl Has a Big Problem
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AFTER looking over a few back copies of POPULAR SCIENCE MONTHLY, I found that there was not a single article on chemistry in them. Each of these issues seemed to be about ninety percent aviation and about ten percent shop. Personally I am interested in aviation, but POPULAR SCIENCE MONTHLY is getting to be more air-minded than science-minded.
PopularScience_19310501_0118_005_0022.xml
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Pharmacal Company
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Pharmacal Company
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PopularScience_19310501_0118_005_0023.xml
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15
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Advertisement
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PopularScience_19310501_0118_005_0024.xml
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Old Town Canoe Co.
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Old Town Canoe Co.
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PopularScience_19310501_0118_005_0025.xml
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15
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FOLMER GRAFLEX CORPORATION
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FOLMER GRAFLEX CORPORATION
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PopularScience_19310501_0118_005_0026.xml
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16
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Masonite Corporation
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Masonite Corporation
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PopularScience_19310501_0118_005_0027.xml
article
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17,18,19,20,143
LEADING ARTICLES
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Giant Laboratory Reveals Secrets of Foolproof Flight
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MARSHALL ANDREWS
NOT long ago a group of aeronautical engineers stood at the Anacostia Naval Air Station, near Washington, D. C., and watched a newly designed Navy bomber howl down from the skies in a 6,000-foot vertical dive. Attached to the plane was a 1,000-pound bomb.
PopularScience_19310501_0118_005_0028.xml
article
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21,22,134
LEADING ARTICLES
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Seek Drug to Save Dope Fiends
Research Chemists Attack Narcotics to Find Their Habit-Forming Secret and Produce Harmless Substitute to Cure Addicts and End Vicious Trade
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GEORGE LEE DOWD
WHAT gives dope its habit-forming property? At present no one can answer that question, but chemists in a special laboratory at the University of Virginia are trying to find the answer. They are seeking a “dopeless dope” that may rescue an army of unfortunates from the body and soul destroying habit that enslaves them.
PopularScience_19310501_0118_005_0029.xml
article
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23,24,25,132,133
LEADING ARTICLES
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Soviet Slaves Rebuild Red Russia
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MICHEL MOK
INTO the next ten years the Russian people must pack the work of a century, or the Soviet’s big plan to turn Russia into an up-to-date industrial nation will fail. These, in substance, were the words, a few weeks ago, of Joseph Stalin, dictator of Russia.
PopularScience_19310501_0118_005_0030.xml
article
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26,27,141,142,143
LEADING ARTICLES
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Pill Box Camera Takes Big Pictures
Instruments That Take 40,000 Pictures a Second and Make a Snapshot with Artificial Light Are Other Photographic Marvels.
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ALDEN P. ARMAGNAC
A NEW YORK inventor is building for himself a camera the size of a small pill box. It will be so small that he can conceal it in the palm of his hand. Yet its diminutive pictures will be easily enlarged to standard snapshot size, or larger, with perfect clearness.
PopularScience_19310501_0118_005_0031.xml
article
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LEADING ARTICLES
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Spinner Plane Bids for Air Supremacy
Revolutionary changes in aircraft may follow use of new type propeller that adds to speed and is silent.
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A DESIGN for a siren gave Christian A. Volf, Danish-born acoustical engineer, an idea that may lead to such a new departure in aviation as the aerial leviathan on this page. One day in his New York City laboratory, Volf was struck with the likeness between the spinning rotor that makes a siren’s whine and an airplane’s whirling propeller.
PopularScience_19310501_0118_005_0032.xml
article
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29,30,31,123,124
LEADING ARTICLES
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Tony FOKKER Wizard of Flight
Thrills and inspiring determination mark the life story of this great aviation pioneer as it will be told in this and succeeding issues.
Part 1—Fired from School He Flies to Fame and Wealth
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ROBERT E. MARTIN
CHARLES A. LINDBERGH recently told this writer he considers Anthony Fokker the greatest airplane designer of the world. His habitual caution in using superlatives makes such praise even more emphatic. Reflecting upon it later, it occurred to me that these two, the world’s premier flyer and its greatest designer, resemble each other in important respects.
PopularScience_19310501_0118_005_0033.xml
article
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UNUSUAL FACTS AND IDEAS
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ALL MEAT IN CARTONS IN NEW BUTCHER SHOP
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HOUSEWIVES of Evanston, Ill., find a new “butcherless” butcher shop recently opened there a convenience when buying meat. It is one of a group planned to sell exclusively the new “packaged” meat. Soft carpets cover its floors, tables and comfortable chairs are arrayed along one wall.
PopularScience_19310501_0118_005_0034.xml
article
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NEW PROCESSES AND INVENTIONS
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ELECTRIC OUTBOARD MOTOR RUNS CANOE
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CANOES and small rowboats are quickly converted to motor boats by a new electric outboard motor, which substitutes a quiet hum for the chugging of the conventional outboard. Power is supplied by a six-volt battery. The motor, which was developed in Long Beach, Calif., can run for about three hours on one charge, at a speed about equal to fast rowing.
PopularScience_19310501_0118_005_0035.xml
article
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RADIO
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MOHAMMEDANS CALLED TO PRAYER BY RADIO
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FOR many centuries priests have toiled up the steep stairs of tall towers in Mohammedan churches to send their wailing call to prayer floating over cities of the East. Science, however, is planning to lighten their labors. Recent reports that have been received from Turkey say that radio engineers are experimenting with huge loudspeakers mounted at the tops of towers and connected to one central broadcasting station.
PopularScience_19310501_0118_005_0036.xml
article
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NEW PROCESSES AND INVENTIONS
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NEW HOSPITAL PHONE CALLS NURSE
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Now a hospital patient can talk to the nurse at any time, whether she is in the room or not. An ingenious microphone-and-loudspeaker system makes this possible. A patient who desires attention merely presses a push button lying on the bed near at hand.
PopularScience_19310501_0118_005_0037.xml
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Advertisement
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PopularScience_19310501_0118_005_0038.xml
article
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MODELS
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BIG MODEL OF GLIDER FLIES 32 MINUTES
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A MODEL glider that Martin Moad, Los Angeles, Calif., high school boy, built recently gave him a four-mile chase over hill and dale. When he launched it with a rubber cord from a 450-foot hill, it breasted rising air currents so successfully that a long straightaway pursuit followed before Moad could recover the model.
PopularScience_19310501_0118_005_0039.xml
article
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COLORED SNOW MYSTERY AT LAST EXPLAINED
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YELLOW, black, red, and green snow are curiosities reported from many parts of the earth, belying the familiar phrase “white as snow.” Long the subject of controversy, the peculiar tints of these forms of snow have been explained by modern science.
PopularScience_19310501_0118_005_0040.xml
article
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RADIO
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BIG RADIO CITY SHOWN MODELED IN PLASTER
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EARLY this summer, workmen and steam shovels will begin work on the greatest private development ever undertaken in America—New York’s $250,000,000 Radio City, financed by John D. Rockefeller, Jr. By the fall of 1933 they will have completed what will be a center of music, opera, and radio and television broadcasting.
PopularScience_19310501_0118_005_0041.xml
article
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AUTOMOBILES
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TIRE CHAINS PUT ON AUTOMATICALLY
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WHEN a motorist needs chains on his wheels, all he has to do is pull a lever beside his emergency brake handle. This is the feat of an automatic tire chain applier invented by B. A. Small, of Roanoke, Va. When the driver pulls the control lever beside him, a pair of devices beneath the rear part of the running boards go into action.
PopularScience_19310501_0118_005_0042.xml
article
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UNUSUAL FACTS AND IDEAS
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SOLDIERS AT BASEBALL WEAR GAS MASKS
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EVERYONE but the umpire wore a gas mask, when soldiers at Fort Wayne, Mich., recently staged a baseball game. Officers here have adopted a novel policy to accustom the men to the feel of the respirators .They are required to wear the devices when playing games, so that they will become used to breathing through them under the strain of wartime battles, and hence will be less likely to expose themselves to serious poisoning in an effort to escape momentarily from the restraint of the mask.
PopularScience_19310501_0118_005_0043.xml
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UNUSUAL FACTS AND IDEAS
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CUBANS USE PALM LEAVES AS ’CHUTES
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LONG before aviators thought of leaping with parachutes, fearless Cuban natives invented a substitute to speed their descent from the tops of royal palm trees. Here the camera man snapped a remarkable picture of one of them, Pepe Garcia, as he takes the air in a seventy-five-foot drop, clutching a bundle of palm fronds.
PopularScience_19310501_0118_005_0044.xml
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PORTABLE BERRY BEDS
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VISITORS to Florida may now rent their own strawberry patches for the season. The “canned” strawberry beds are delivered in concrete troughs four or five wide, with a low rim so that they may hold water. Each plant is set in a small can with holes punched in the bottom in order to allow water to get at the roots.
PopularScience_19310501_0118_005_0045.xml
article
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AUTOMOBILES
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NEW TRUCK DESIGNED TO LAY ITS OWN ROAD
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ROADS unrolled from a spool—that is the dream of Benjamin F. Morningstar, Park Ridge, N. J., inventor. Recently he exhibited a model of a truck he has designed which could lay a 100-foot section of corduroy road in two minutes across a swamp.
PopularScience_19310501_0118_005_0046.xml
article
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AUTOMOBILES
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POCKET SIZED DEVICE TESTS AUTO BRAKES
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THREE small steel balls rolling in inverted “V” slots of different slopes in a piece of cardboard allow a motorist to test his brakes without leaving the wheel. The tester is placed level and parallel to the side of the car. With the car going twenty miles an hour, the brakes are suddenly applied.
PopularScience_19310501_0118_005_0047.xml
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STRANGE IDIOMS IN MOVIE LANGUAGE
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DON’T be alarmed if you visit a movie studio and are warned to look out for the dynamite. It doesn’t mean high explosive. According to a glossary of movie terms compiled by the Academy of Motion Picture Arts and Sciences, it refers to “an open connection box into which the studio lamps are plugged—dangerous if stepped on.” “Canaries” are unidentified. high pitched noises in the sound recording system. A “bug” is defined as an insect that flies across the set while a scene is being photographed, usually spoiling it.
PopularScience_19310501_0118_005_0048.xml
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UNUSUAL FACTS AND IDEAS
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Big and Little Kings of the Rail
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PopularScience_19310501_0118_005_0049.xml
article
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RADIO
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LETTER PUT ON AIR BY RADIO TYPEWRITER
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IN A DETROIT hotel the other day engineers gathered to watch a demonstration of one of the latest wonders of radio, a typewriter which sent typed letters through the air without the aid of wires. At the receiving end they are automatically reproduced upon a typewriter without the touch of a human hand.
PopularScience_19310501_0118_005_0050.xml
article
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UNUSUAL FACTS AND IDEAS
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BAKE STEEL BISCUITS IN HEAT TEST
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STEEL “biscuits” were baked in ordinary biscuit pans as a test in San Francisco the other day before a group of metallurgical experts. Unlike the biscuits that mother makes, which are all from the same batch of dough, each of the steel biscuits was made from a different mixture of metal.
PopularScience_19310501_0118_005_0051.xml
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ASTRONOMY
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GIANT TELESCOPE SITE TO BE CHOSEN SOON
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AUTHORITIES at the Mount Wilson Observatory, California, soon may announce the site for the huge new 200-inch telescope now under construction. The big telescope must be placed on a mountain top, with plenty of clear air around it. It must be in a position where there is little wind, and where there is a relatively slight change in temperature during the day and night.
PopularScience_19310501_0118_005_0052.xml
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NEW PROCESSES AND INVENTIONS
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ONE MAN CAN LIFT A TELEGRAPH POLE
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ONE man can easily lift a 2,000-pound telegraph pole with a jack recently developed by a California power company. When he swings the handle a worm-and-gear drive elevates the lifting arm. The base is so large that it may be used on soft or uneven ground. When the lifting arm is lowered, it can be slipped under a pole with a clearance of one half inch.
PopularScience_19310501_0118_005_0053.xml
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AUTOMOBILES
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QUEER SLOTTED SHIELD FITS HEADLIGHT BULB
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ALL sorts of shields have been designed to fit over the bulb in the automobile headlight with the object of cutting down the glare. Here is a novel type fitted with a horizontally slotted spherical front piece that allows some of the light to reach the road directly in front of the car.
PopularScience_19310501_0118_005_0054.xml
article
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UNUSUAL FACTS AND IDEAS
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WINDOW SHOWS HOW JURORS ARE CHOSEN
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NOT everyone called to serve on a jury knows just how his name happened to be chosen. The illustration shows how names, written on slips of paper, are tumbled in a revolving wheel-like cage and then drawn one by one. An innovation in this particular machine was the idea of jury commissioners of Cuyahoga County, Ohio. Tiring of complaints that the jury-selecting wheel was fixed so that certain names fell into hidden pockets, they put a large glass window in one side.
PopularScience_19310501_0118_005_0055.xml
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AVIATION
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HELICOPTER RAILWAY RUNS IN FRANCE
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ODDEST of railway cars is a vehicle that speeds at fifty miles an hour along a private railway near Paris, France. It carries models of helicopters, or vertical-flying aircraft, to be tested for their lifting power and stability. The user of this strange equipment is Louis Damblanc, French aeronautical engineer, who for years has predicted the ultimate triumph of the helicopter over conventional airplanes.
PopularScience_19310501_0118_005_0056.xml
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UNUSUAL FACTS AND IDEAS
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USE LIE DETECTOR IN MURDER CASE
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JUST how a “lie detector” traps the prevaricating criminal was strikingly shown not long ago when the Illinois State Criminologist, Dr. John A. Larson, obtained permission to try the device upon a Chinaman accused of murder. This type of machine, developed at the University of Chicago, makes a chart of a suspect's pulse and breathing while he is being questioned.
PopularScience_19310501_0118_005_0057.xml
article
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AUTOMOBILES
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DOOR OF NEW TRUCK FORMS GANGWAY
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A TRUCK body recently developed by a Portland, Ore., department store makes loading easy and relieves traffic congestion. Side doors open downward, forming a gangway from the sidewalk. Loaded hand trucks are pushed up this inclined runway and remain in the delivery truck when it goes out on its route.
PopularScience_19310501_0118_005_0058.xml
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40,41,125
LEADING ARTICLES
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Dead Wells Made to Spout Oil
Gas and Oil Pumped into Exhausted Fields Start New Flow of Liquid Gold
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STERLING GLEASON
AN OLD oil field, almost exhausted by a quarter century of draining, has just sprung into the spotlight by suddenly yielding a heavy flow of high gravity oil. Ancient wells whose output had dwindled to a mere trickle of oil from a sluggish pump have astounded oil experts by beginning to flow at the rate of several hundred barrels of thirty-two-degree oil a day.
PopularScience_19310501_0118_005_0059.xml
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42,43,138,140
LEADING ARTICLES
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Costly Nuisances Yield Riches
Miracles of Change in the Industrial World Show How By-products That Caused Big Losses Have Been Transformed into Valuable Assets by Work of an Army of Chemists
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JESSE F. GELDERS
BELGIUM’S mysterious poison fog is no longer a mystery. The source of its death-dealing fumes, which claimed seventy human victims and a large number of cattle, has been traced to near-by factories from which sulphurous fumes escaped.
PopularScience_19310501_0118_005_0060.xml
article
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PHOTOGRAPHY
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CAMERA FILMS INSIDE OF PIPES AND GUNS
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MAKING a motion picture camera peer into small deep holes and record the condition of their inner surfaces is the achievement of German engineers. They developed a “pipe camera” for this purpose as an aid in inspecting the inside surfaces of pipes and gun barrels.
PopularScience_19310501_0118_005_0061.xml
article
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MODELS
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LINERS SHOWN ON MODEL OCEAN
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TINY steamers are pushed over a huge brightly-painted relief map of the world in a show window of a steamship company in Berlin, Germany. By this mechanical means the passers-by are shown the location of each of the company’s vessels on the ocean highways.
PopularScience_19310501_0118_005_0062.xml
article
45
45
UNUSUAL FACTS AND IDEAS
[no value]
Flyers Make First Air Map of North Magnetic Pole
[no value]
[no value]
[no value]
[no value]
NOW that the North Pole has been conquered by dog team, airplane, and dirigible, northward-bound explorers are turning to less widely-advertised goals. Recently two Canadian government flyers, Major L. T. Burwash and W. E. Gilbert, became the first to reach the little-known North Magnetic Pole by air.
PopularScience_19310501_0118_005_0063.xml
article
45
45
UNUSUAL FACTS AND IDEAS
[no value]
BOOK MATCHES GET STRANGE SHAPES
[no value]
[no value]
[no value]
[no value]
SOON you will see, if you have not already done so, a new kink in book matches. An ingenious manufacturer recently conceived the idea of shaping the match “sticks” themselves to resemble the product whose merits the cover describes. Thus they are shaped to simulate cigars, tooth paste tubes, and bottles of soft drinks according to the needs of the advertiser.
PopularScience_19310501_0118_005_0064.xml
article
46
46
HEALTH AND HYGIENE
[no value]
USE CATHODE RAY TO TEST LUNGS
[no value]
[no value]
[no value]
[no value]
QUICK detection and diagnosis of lung trouble are made possible by the invention of two German physicians. Their new instrument resembles a stethoscope, but wires carrying an electric current take the place of a listening tube. For the physician’s ear is substituted the cathode ray, which has hitherto been associated with such uses as the measuring of lightning flashes and other high-voltage currents.
PopularScience_19310501_0118_005_0065.xml
article
46
46
NEW PROCESSES AND INVENTIONS
[no value]
TINY ELECTRIC EYE NOW READY FOR AMATEURS
[no value]
[no value]
[no value]
[no value]
A SMALL cheap photo-electric cell, or electric eye, has been developed by a manufacturing firm in Camden, N. J. This little electrical device has the power to release a current of electricity whenever light strikes it. Although this model has been developed for the use of amateur experimenters, it can be put to many useful tasks.
PopularScience_19310501_0118_005_0066.xml
article
46
46
NATURE
[no value]
MAGNIFY MINUTE WATER LIFE MILLION TIMES
[no value]
[no value]
[no value]
[no value]
IF A HALF-INCH cube of water from the average pond were suddenly enlarged to a million times its natural volume, an observer might see with a shock some of the strange creatures that live there. That startling feat of magnification was performed not long ago at the American Museum of Natural History, in New York, where glass models form an exhibit of “rotifers” and other oddities of aquatic life magnified a millionfold.
PopularScience_19310501_0118_005_0067.xml
article
46
46
UNUSUAL FACTS AND IDEAS
[no value]
TRAPS UP IN THE AIR CAPTURE BUGS
[no value]
[no value]
[no value]
[no value]
GOVERNMENT entomologists are now going up in the air to trap insect pests. Their latest device is a wind-vane trap, which keeps its mouth wide open in the direction of the wind to catch insects enroute from their breeding places to sugar-beet fields in the West.
PopularScience_19310501_0118_005_0068.xml
article
46
46
UNUSUAL FACTS AND IDEAS
[no value]
FREIGHT BY WIRE IN COFFEE LAND
[no value]
[no value]
[no value]
[no value]
SINGING wires of aerial cable-ways form the chief means of communication between cities of the coffee-growing district of Colombia, in South America. These cities are isolated from each other by mountain ranges and impassable jungles.
PopularScience_19310501_0118_005_0069.xml
article
47
47
AUTOMOBILES
[no value]
GIANT TRUCK TURNS CORNER EASILY
[no value]
[no value]
[no value]
[no value]
FROM ships to mammoth motor trucks is an easy step for Anton Flettner, noted German inventor. A few years ago his “Flettner rotorship,” a strange craft propelled by vertical revolving stacks instead of screws or sails, startled the world by traveling across the Atlantic.
PopularScience_19310501_0118_005_0070.xml
article
47
47
[no value]
[no value]
FREE-WINGED PLANE ABLE TO FLY ITSELF
[no value]
[no value]
[no value]
[no value]
SUCCESSFULLY demonstrating in test flights that it practically can fly itself, land, or take off without the aid of a pilot and cannot stall, spin, sideslip or stunt, a new “free-winged” airplane is scheduled to be produced on large scale by its Los Angeles designer, G. Wilbur Cornelius.
PopularScience_19310501_0118_005_0071.xml
article
47
47
UNUSUAL FACTS AND IDEAS
[no value]
GUN SHOOTS MAIL FROM SHIP TO SHIP
[no value]
[no value]
[no value]
[no value]
MAIL sometimes soars from a gun in the British navy. This rarely used way of delivering letters was demonstrated not long ago when H. M. S. Nelson left England to be a guest at the American Navy’s maneuvers off Panama. The destroyer Windsor steamed up to the departing Nelson and hove to.
PopularScience_19310501_0118_005_0072.xml
article
47
47
UNUSUAL FACTS AND IDEAS
[no value]
TOSS BOTTLES INTO SEA IN STUDY OF WINDS
[no value]
[no value]
[no value]
[no value]
ALMOST 500 bottles are thrown overboard daily from British ships into the oceans of the world and allowed to drift where they will. They are not empty, for each contains a set of printed instructions, besides a record of the point at which it was dropped.
PopularScience_19310501_0118_005_0073.xml
article
48
48
NATURE
[no value]
Daring Cameraman Snaps Animals on Desolate Isle
[no value]
[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0074.xml
article
49
49,137
LEADING ARTICLES
[no value]
Map Earthquakes to Save Roads
TALKING LIGHTHOUSE NOW GUIDES SHIPS
[no value]
[no value]
TOM WHITE
WHEN an earthquake moves a good-sized piece of land ten or twelve feet, everything on it goes with it. Naturally the men who build highways and dams would like to know in advance whether a local earthquake is likely to disrupt their handiwork.
PopularScience_19310501_0118_005_0075.xml
article
50
50
HEALTH AND HYGIENE
[no value]
NEW X-RAY MACHINE SHOWS OBJECT’S DEPTH
[no value]
[no value]
[no value]
[no value]
Now a doctor may see a patient’s internal organs in relief, unlike the flat view given by an ordinary X-ray machine. A “three-dimensional” X-ray outfit that accomplishes this surprising result is the recent invention of Dr. Jesse William DuMond and Archer Hoyt, of the California Institute of Technology, located at Pasadena.
PopularScience_19310501_0118_005_0076.xml
article
50
50
NEW PROCESSES AND INVENTIONS
[no value]
MOTORIZED WORKSHOP FITS IN CLOSET
[no value]
[no value]
[no value]
[no value]
FEW are the homes without enough space for a home workshop, since the recent introduction of a novel woodworking cabinet that folds up and can be stored in a corner of a clothes closet. Completely motorized, its eight power tools perform practically any task that the householder desires.
PopularScience_19310501_0118_005_0077.xml
article
50
50
UNUSUAL FACTS AND IDEAS
[no value]
GERMAN STREET CAR CUT IN TWO
[no value]
[no value]
[no value]
[no value]
“JOINTED” street cars have been developed by German engineers as a means of providing additional comfort to riders and greater ease of operation on sharp curves. The new trolleys are really two cars, joined together by an accordionlike device between them, much like the connections between cars of a vestibuled American railway train.
PopularScience_19310501_0118_005_0078.xml
article
51
51
UNUSUAL FACTS AND IDEAS
[no value]
BLINDFOLDS GOLFER TO TEACH SWING
[no value]
[no value]
[no value]
[no value]
PRACTICAL experiments at the University of Illinois prove that the best way for beginners to learn the golf swing is by the use of blindfolds. Dr. Coleman R. Griffith taught two groups, one by the "blinders” method and the other by the “keep your eye on the ball” system.
PopularScience_19310501_0118_005_0079.xml
article
51
51
AVIATION
[no value]
LOUDSPEAKERS TO HELP MOOR HUGE AIRSHIP
[no value]
[no value]
[no value]
[no value]
WHEN the naval airship Los Angeles drones in for a landing at the Lakehurst, N. J., air station, her commander’s voice now personally directs the ground crew who moor the giant ship. Recently six huge loudspeakers were added to the mobile mooring mast that tows the big airship into her hangar.
PopularScience_19310501_0118_005_0080.xml
article
51
51
UNUSUAL FACTS AND IDEAS
[no value]
DEEPEST OIL NOW NEAR THE TWO-MILE LIMIT
[no value]
[no value]
[no value]
[no value]
DEEPER and deeper into the earth’s crust are poking the drills with which men bore for oil. Nearly two miles deep, or 9,700 feet, is the world’s record reached not long ago by a well in a California oil field, fifty miles northwest of Bakersfield.
PopularScience_19310501_0118_005_0081.xml
article
51
51
AUTOMOBILES
[no value]
DIESEL-POWERED AUTO READY TO RACE
[no value]
[no value]
[no value]
[no value]
THE world's first Diesel racing car recently sped over the sands of Daytona Beach, Fla. It attained a speed of more, than 100 miles an hour. So promising was its performance that its designer, C. L. Cummins, of Columbus, Ind., pioneer builder of Diesel automobiles (P.S.M., May ’30, p.52), has announced he will enter it in the famous 500-mile race to be held at Indianapolis, Ind., on Memorial Day.
PopularScience_19310501_0118_005_0082.xml
article
51
51
AUTOMOBILES
[no value]
NEW CAR GEAR SHIFT IS AUTOMATIC
[no value]
[no value]
[no value]
[no value]
AUTOMATIC shifting of automobile gears is the purpose of a new device designed by a Cincinnati, Ohio, inventor. When starting a car, the gears are shifted from low to high without attention from the driver. It is claimed that if the car strikes muddy roads or heavy sand, the gears automatically shift back to low.
PopularScience_19310501_0118_005_0083.xml
article
51
51
UNUSUAL FACTS AND IDEAS
[no value]
ARC-WELDED FURNACE BIGGEST EVER MADE
[no value]
[no value]
[no value]
[no value]
TEN thousand pounds of metal went into what is said to be the largest warm-air furnace in the world, just completed for a large church in Rochester, Minn. An interesting feature of its construction was the use of electric welding as a substitute for riveting.
PopularScience_19310501_0118_005_0084.xml
article
51
51
NATURE
[no value]
FISH SHOOTS ITS PREY
[no value]
[no value]
[no value]
[no value]
THE story of a fish that “shoots” its prey was brought from Siam recently by Dr. Hugh M. Smith, scientific adviser on fisheries to the Siamese government. If an insect or spider is perched on overhanging brush or tree roots near the water, the shooting fish knocks it over with a squirt of water.
PopularScience_19310501_0118_005_0085.xml
article
52
52
AVIATION
[no value]
Akron, World's Greatest Airship, Gets Outer Covering
[no value]
[no value]
[no value]
[no value]
Now receiving her glistening “overcoat” of shiny fabric, the Navy’s newest and greatest airship Akron is nearing completion in her dock at Akron, Ohio. Workmen are rushing the work so that her maiden flight, it is announced, will take place early in June.
PopularScience_19310501_0118_005_0086.xml
article
52
52
AVIATION
[no value]
NAVY TESTS MYSTERY PLANE
[no value]
[no value]
[no value]
[no value]
A TRIM little biplane, said to be the speediest fighting plane in the world, was tried out the other day at Mitchel Field, N. Y. Navy officials refused to give out any information about the new hornet of the skies, but it was believed to have a top speed of about 300 miles an hour and to be able to attain an altitude of 29,000 feet.
PopularScience_19310501_0118_005_0087.xml
article
53
53
AVIATION
[no value]
FLYERS TEST SKILL BURSTING BALLOONS
[no value]
[no value]
[no value]
[no value]
TO THRILL airplane pilots and spectators and to test an aviator’s skill in speedy maneuvers, a flying school at San Diego, Calif., has revived balloon-bursting. A door is removed from a brougham airplane and four huge, gas-filled balloons are placed in the cabin. An assistant pilot gets in with them. The ship takes off, followed by another. Then the four balloons are pushed out of the cabin, in quick succession.
PopularScience_19310501_0118_005_0088.xml
article
53
53
AVIATION
[no value]
TRAIN PILOTS TO SHOOT ON GROUND
[no value]
[no value]
[no value]
[no value]
PRACTICE of aerial machine gun fire on the ground is made possible by a device which has been installed at a Texas flying field. The ground device, used in training airmen, is a wooden framed cockpit with a machine gun fitted to it. The frame is pivoted in such a manner that it will turn or nose down or up like a flying plane so the pilot may train his gun on the target.
PopularScience_19310501_0118_005_0089.xml
article
53
53
AVIATION
[no value]
AIR GIVES PLANE ITS HARDEST BUMPS
[no value]
[no value]
[no value]
[no value]
AN AIRPLANE gets worse bumps in the air than when it is landing. That was one of the surprising facts recently discovered when Westing-house engineers fitted a plane at the Newark Airport, N. J., with a new electric shock recorder. Heretofore such shocks could only be estimated by mathematical calculations, after testing models in a wind tunnel.
PopularScience_19310501_0118_005_0090.xml
article
53
53
AVIATION
[no value]
NAVY PLANS BIG METAL AIRSHIP
[no value]
[no value]
[no value]
[no value]
BIGGER than the giant airship Los Angeles will be an all-metal dirigible for the U. S. Navy on which work is expected to start shortly. It is to be patterned after the much smaller metal-clad blimp built for the Navy some time ago by a Detroit aircraft company, which has proved itself in numerous cruises.
PopularScience_19310501_0118_005_0091.xml
article
54
54
AVIATION
[no value]
DRAGON FLY PLANE MEETS TEST
[no value]
[no value]
[no value]
[no value]
AN ODD looking little plane is the one recently perfected by Earl E. McClary, aeronautical engineer, of Huntington Park, Calif. It is a cabin monoplane with fuselage cut away in unusual fashion in order to give the pusher propeller room to turn.
PopularScience_19310501_0118_005_0092.xml
article
54
54
AVIATION
[no value]
PUSHER PLANE USES LITTLE FUEL
[no value]
[no value]
[no value]
[no value]
ONCE more builders are turning to the “pusher” type of airplane in which the propeller is mounted at the rear of the wing, reviving early styles in aviation. A little two-place monoplane recently designed by Hammondsport, New York, airplane builders is driven by a forty-horsepower motor turning a pusher propeller.
PopularScience_19310501_0118_005_0093.xml
article
54
54
AVIATION
[no value]
TINY AIRPLANE HAS NO TAIL FLAPS
[no value]
[no value]
[no value]
[no value]
A TINY airplane which needs no elevators, or tail to control ascent and descent, was flown recently in Tellerton, England. The ship, which is a high-winged single-seated monoplane, has wings of an unusual design. The after edge of its wing tips extend back beyond the center of the wing, forming a shallow “V” in a horizontal plane.
PopularScience_19310501_0118_005_0094.xml
article
54
54
AVIATION
[no value]
UNUSUAL SPORT PLANE HAS NO FUSELAGE
[no value]
[no value]
[no value]
[no value]
PILOT and passenger ride in a car shaped like a Zeppelin gondola, beneath the wings of a novel sport plane tried out the other day at Lincoln, Nebr. Devoid of fuselage and with only the suggestion of a tail, the strange craft is an innovation among light airplanes.
PopularScience_19310501_0118_005_0095.xml
article
54
54
AVIATION
[no value]
AUTOGIRO TO AID COPS
[no value]
[no value]
[no value]
[no value]
AUTOGIRO police may be an actuality in New York City, one of these days. The New York Police Department is investigating the possibilities of this odd type of “windmill plane,” which could land in city parks within congested areas. New York was one of the first cities to employ conventional planes as an aid it its police work.
PopularScience_19310501_0118_005_0096.xml
article
55
55,122
LEADING ARTICLES
[no value]
Weather Ignores the Groundhog
[no value]
[no value]
[no value]
[no value]
A CHICAGO weather forecaster, C. A. Donnel, recently set aside his official duties long enough to run down a curious bit of weather lore. He checked up on the performance of the groundhog, as a weather prophet, for the last eleven years. On the second of February each year, tradition has it, this small furry animal comes out of his burrow and surveys the world about him.
PopularScience_19310501_0118_005_0097.xml
article
56
56,57,136
LEADING ARTICLES
[no value]
Balsa, Nature’s Miracle Wood, Finds Amazing Uses
Lighter Than Cork, Ecuador's Strange Product Makes Fine Life Preservers and Insulates Against Noise and Heat
[no value]
[no value]
CLAYTON R. SLAWTER
ENGINEERS of a big silk manufacturing firm in New York City were faced recently with a difficult problem. Vibrations caused by heavy machinery in their plant on the twenty-third floor of a skyscraper ran down the building’s steel framework and were felt on every floor.
PopularScience_19310501_0118_005_0098.xml
article
58
58,59,126,127
LEADING ARTICLES
[no value]
New Glider Records Come Fast
Soaring enthusiasts prepare for big season, and this year thousands will ride sailing planes—Endurance flights and altitude attempts certain to set new marks as pilots acquire skill in guiding light motorless aircraft
[no value]
[no value]
EDWIN W. TEALE
A TWENTY-MILE flight across the open sea, a half-hour ride on heat currents rising from New York skyscrapers, a thrilling leap on skis with a wing-clipped glider strapped to the jumper’s waist, a swoop across the San Fernando Valley from a California mountain peak, and the trial of a weird rubber monoplane inflated with air have been the high lights of recent glider activity.
PopularScience_19310501_0118_005_0099.xml
article
60
60
NEW PROCESSES AND INVENTIONS
[no value]
NEW MACHINE GUN TOY BLOWS SOAP BUBBLES
[no value]
[no value]
[no value]
[no value]
BUBBLES galore, to delight a child’s heart, are the product of a new toy that forms them with the rapidity of a machine gun. Blowing into its pipe shoots a rapid stream of the colorful bubbles into the air. The novel plaything is filled with soap solution, made by dissolving a supply of prepared soap in a glass of water.
PopularScience_19310501_0118_005_0100.xml
article
60
60
UNUSUAL FACTS AND IDEAS
[no value]
ENGINE SMOKE IS CAUGHT AND CLEANED
[no value]
[no value]
[no value]
[no value]
ONE of the ways that Chicago keeps clean is to prevent locomotives in railroad yards from belching black smoke into the air. At one of its terminals, a specially-constructed hood, like that illustrated above, is swung out over the smokestack of a standing engine while it is getting up steam.
PopularScience_19310501_0118_005_0101.xml
article
60
60
NEW PROCESSES AND INVENTIONS
[no value]
AIR DRIVES FILER AT 5,000 STROKES A MINUTE
[no value]
[no value]
[no value]
[no value]
SPEEDY, accurate filing in the shop is now made easier by an entirely new type of hand tool. It works by compressed air, and makes as many as 5,000 strokes a minute. A unique “file guide,” an eight-sided knob keyed to the spindle, turns the file to guide it over an irregular surface at the touch of thumb and forefinger, while the tool is held steady.
PopularScience_19310501_0118_005_0102.xml
article
60
60
UNUSUAL FACTS AND IDEAS
[no value]
AIR, FREED OF NITROGEN, AIDS DIVER
[no value]
[no value]
[no value]
[no value]
“SYNTHETIC air,” new aid to divers, recently received a successful try-out at the Philadelphia Navy Yard, in anticipation of its use on Sir Hubert Wilkins’ submarine trip across the Arctic Ocean. The man-made product proved better than natural air.
PopularScience_19310501_0118_005_0103.xml
article
61
61
PHOTOGRAPHY
[no value]
FRAME FOR SNAPSHOTS HAS GLASS AND STAND
[no value]
[no value]
[no value]
[no value]
Now even the humble snapshot has a picture frame designed especially for it. A favorite snap of mother, father, or sweetheart slips between two panes of beveled glass and stands upright in this ingenious little frame of modernistic design.
PopularScience_19310501_0118_005_0104.xml
article
61
61
PHOTOGRAPHY
[no value]
CAMERA ON PLANK GETS RARE PHOTOS
[no value]
[no value]
[no value]
[no value]
A NEWS photographer of Omaha, Nebr., invented a “sky hook” for a camera the other day as an aid in taking shots from difficult angles. His camera is mounted at one end of a light plank about eight feet long. A movable wooden rod extends from it to the end of the plank.
PopularScience_19310501_0118_005_0105.xml
article
61
61
NEW PROCESSES AND INVENTIONS
[no value]
RESCUE BASKET SAVES FIRE VICTIMS
[no value]
[no value]
[no value]
[no value]
UP AND down a ladder runs a novel “rescue basket” demonstrated the other day by German firemen. Suggesting the “bo’s’n’s chair” used to lower persons over the side of ships, it makes easy the task of saving invalids from a burning building. The escaping person is helped into the basket at the window’s level and lowered by a rope to the ground.
PopularScience_19310501_0118_005_0106.xml
article
61
61
NEW PROCESSES AND INVENTIONS
[no value]
“WOBBLE METER” SHOWS FATIGUE OF WORKMEN
[no value]
[no value]
[no value]
[no value]
IN THE photo above is shown the “wobble meter,” a machine that measures human fatigue. When the subject stands on a low platform that teeters forward and sideways, two little dials add up the wobbles. They are a direct measure of his tiredness.
PopularScience_19310501_0118_005_0107.xml
article
62
62
Five Minutes of ASTRONOMY
[no value]
MEASURE THE SUN WITH YOUR POCKET RULE
[no value]
[no value]
[no value]
[no value]
FEW people realize that the oval disk of light that is seen on the floor of a darkened room wherever a pencil of sunlight filters through a chink in the blinds is an actual image of the sun. The oval shape is a mere distortion. If a piece of cardboard is held at right angles to the pencil of light, the image becomes a circle, whose diameter can be measured and made the basis of a fairly accurate calculation of the sun’s diameter!
PopularScience_19310501_0118_005_0108.xml
article
62
62
UNUSUAL FACTS AND IDEAS
[no value]
MIGHTIEST CASTING WEIGHS 230 TONS
[no value]
[no value]
[no value]
[no value]
A GIANT among castings is the cylinder jacket for a huge 14,000-ton forging press constructed recently at Bethlehem, Pa. It is made in one piece and weighs 230 tons, 460,000 pounds, or about as much as a large locomotive. Six furnaces working at one time supplied the melted metal for making this titanic casting, said to be the largest ever poured.
PopularScience_19310501_0118_005_0109.xml
article
62
62
RADIO
[no value]
BROADCASTERS TEST SILENT PAPER
[no value]
[no value]
[no value]
[no value]
LEST the rustle of a speaker’s notes destroy the illusion of spontaneity in his spirited oration, a large broadcasting company is trying out a “crackleproof” paper. If successful, it plans to have all speakers use this style of paper for their written speeches.
PopularScience_19310501_0118_005_0110.xml
article
62
62
UNUSUAL FACTS AND IDEAS
[no value]
BIG COAL LOADER STRADDLES RAILWAY
[no value]
[no value]
[no value]
[no value]
AN ENORMOUS German “coal shovel” runs on the outer tracks of a four-track railway, straddling the two center tracks. The grotesque looking machine digs coal out of a huge storage pile and loads it into cars on the center tracks. Its swinging boom digs to a maximum depth of 100 feet. In an hour it loads about 1,242 tons.
PopularScience_19310501_0118_005_0111.xml
article
63
63
HEALTH AND HYGIENE
[no value]
RESPIRATOR FOR BABIES MAY SAVE MANY LIVES
[no value]
[no value]
[no value]
[no value]
BABIES with breathing troubles at a Chicago hospital receive treatment in a strange looking machine. It is an artificial respirator, for use when tiny lungs have difficulty doing their work. Feeding oxygen to infants through masks, or forcing their breath by mechanical means, often was injurious or irritating.
PopularScience_19310501_0118_005_0112.xml
article
63
63
UNUSUAL FACTS AND IDEAS
[no value]
METAL POLO PONY USED IN PRACTICE
[no value]
[no value]
[no value]
[no value]
A POLO pony made of metal helps Robert W. Harasta, of Los Angeles, to improve his game. Harasta devised a make-believe mount from which he could practice. The product of his handiwork was a hobbyhorse standing on adjustable legs. Changing their height gives Harasta a chance to experiment with strokes from ponies of different stature.
PopularScience_19310501_0118_005_0113.xml
article
63
63
PHOTOGRAPHY
[no value]
MOVING PICTURE MADE OF TELEVISION IMAGES
[no value]
[no value]
[no value]
[no value]
SUCCESSFUL photographs of television images, made recently at the Schenectady, N. Y., laboratory of Dr. E. F. W. Alexanderson, give the man in the street his first view of “what television looks like.” Only a privileged few, to date, have been able with their own eyes to witness actual demonstrations of seeing at a distance, for at present television is admittedly still in the experimental stage.
PopularScience_19310501_0118_005_0114.xml
article
63
63
AUTOMOBILES
[no value]
BUS FOR INDIAN PRINCE CARRIES 27
[no value]
[no value]
[no value]
[no value]
WINDOWS that you can see out of, but not in through, a sliding roof to let in sunlight by day, and a 225,000-candlepower searchlight to illuminate the way at night are features of two motor buses just completed in England for an Indian prince.
PopularScience_19310501_0118_005_0115.xml
article
63
63
UNUSUAL FACTS AND IDEAS
[no value]
MAINE COAST LEADS COUNTRY IN FOG
[no value]
[no value]
[no value]
[no value]
IN WINNING the honor of being the foggiest part of the United States for 1930, the coast of Maine took first, second and third places. Moose Peak Lighthouse won first place with 1,526 hours of fog. Libby Island and Petit Manan, also on the Maine coast, won second and third places.
PopularScience_19310501_0118_005_0116.xml
article
64
64
NEW PROCESSES AND INVENTIONS
[no value]
REVOLVING FLOWERPOT TURNS PLANT TO SUN
[no value]
[no value]
[no value]
[no value]
EVERY part of a plant’s foliage gets its share of sunlight with a new “sun-chasing” stand for a flowerpot invented by a Winchester, Mass., man. The stand revolves on ball bearings at the finger’s touch. Given an occasional turn, it protects plants against becoming lop-sided from unequal growth.
PopularScience_19310501_0118_005_0117.xml
article
64
64
PHOTOGRAPHY
[no value]
TRIPOD ON WHEELS TO SHIFT MOVIE CAMERA
[no value]
[no value]
[no value]
[no value]
IN PRODUCING talking pictures, it is often necessary to move the camera while the scene is being filmed and the sound to accompany it is being recorded. The most recent device to facilitate this operation without noise or jar is a flexible camera mounting by which the tripod can be raised on wheels and the entire outfit moved to a new position.
PopularScience_19310501_0118_005_0118.xml
article
64
64
HEALTH AND HYGIENE
[no value]
OLD AGE DUE TO BAD DIET
[no value]
[no value]
[no value]
[no value]
SLOWING down the blood stream by self poisoning, according to Dr. Arnold Lorand, of Carlsbad, Germany, is one of the principal causes of old age. It is brought about by eating insufficient supplies of mineral salts and gland stimulating chemicals.
PopularScience_19310501_0118_005_0119.xml
article
64
64
ENGINEERING
[no value]
WELDING BIG BUILDING ENDS RIVET RACKET
[no value]
[no value]
[no value]
[no value]
A YEAR or so ago the board of directors of a New York City trust company sent out engraved notes of apology to some 500 of its neighbors, asking their indulgence “during the unavoidably noisy weeks” that would occur while rivets were being placed in its new building.
PopularScience_19310501_0118_005_0120.xml
article
64
64
AUTOMOBILES
[no value]
BUILDS HIS GARAGE DOOR OPENER
[no value]
[no value]
[no value]
[no value]
A USED washing machine motor, a length of rope, some lumber, and a few pieces of gas pipe—with these materials, Charles Johnson, of Cleveland, Ohio, fashioned an automatic garage door opener that has given him unfailing service without need of maintenance or repair.
PopularScience_19310501_0118_005_0121.xml
article
65
65
NEW PROCESSES AND INVENTIONS
[no value]
NEW GUN HURLS SHELL FIVE MILES STRAIGHT UP
[no value]
[no value]
[no value]
[no value]
THE newest war terror is an anti-aircraft gun, built in England, that could fire a shell over the top of Mt. Everest, world’s highest peak. The weapon’s extraordinary vertical range enables it to destroy airplanes flying as high as five and a half miles above the earth’s surface. Few planes climb higher. Developed according to an entirely new pattern by the famous firearms concern of Vickers, the gun is controlled by a device that holds it automatically on the target.
PopularScience_19310501_0118_005_0122.xml
article
65
65
NEW PROCESSES AND INVENTIONS
[no value]
ELECTRICITY TESTS SOIL FOR CROPS
[no value]
[no value]
[no value]
[no value]
Now electricity tests your soil, and tells you what sort of crops you may expect from a hitherto unused piece of land. A compact electric instrument, that weighs but nine pounds with its wooden box, can be carried anywhere in the field. A sample of soil to be tested is placed in a cup on the instrument.
PopularScience_19310501_0118_005_0123.xml
article
65
65
UNUSUAL FACTS AND IDEAS
[no value]
FLAT HAILSTONES FALL ON ISLAND OF CYPRUS
[no value]
[no value]
[no value]
[no value]
“FLAT” hailstones, shaped like coins, were a novelty that fell recently on the island of Cyprus. They melted first at the centers, forming doughnutlike rings. Recently reported to the British Meteorological Office in London, they remain a curiosity for which that office is unable to give an explanation.
PopularScience_19310501_0118_005_0124.xml
article
65
65
NEW PROCESSES AND INVENTIONS
[no value]
LETTERS FOR SIGN HELD IN PLACE BY MAGNETS
[no value]
[no value]
[no value]
[no value]
MAGNETIZED letters are used in a new type of sign perfected recently by an Omaha, Neb., firm. Mounted on a back-ground of steel, they are held against it by the magnetic force. Both background and letters are made in varying sizes, each letter having two or more magnets in its back, depending on its size.
PopularScience_19310501_0118_005_0125.xml
article
65
65
UNUSUAL FACTS AND IDEAS
[no value]
SERVE FOOD ON ROTATING BUFFET
[no value]
[no value]
[no value]
[no value]
“MERRY-GO-ROUND” lunch counters are the newest idea in restaurants. So far a dozen of these unusual eating places with revolving tables have been opened on the Pacific coast. They introduce an entirely novel idea in service, and do away with the necessity of employing a staff of waiters.
PopularScience_19310501_0118_005_0126.xml
article
66
66,67
UNUSUAL FACTS AND IDEAS
[no value]
Odd Ferries, New and Old
Photo Story of Strange Craft From the Airplane Service of California to Primitive Boat Run by Man Power in India
[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0127.xml
article
68
68
UNUSUAL FACTS AND IDEAS
[no value]
GAS FROM WASTE NOW HEATS HOUSES
[no value]
[no value]
[no value]
[no value]
CHEAP gas produced from cornstalks and sewage may soon be lighting and heating homes in the corn belt, according to Dr. A. M. Buswell of the University of Illinois. Recent experiments show, that these farm wastes, when placed in a tank eight feet square and eight feet deep, will provide all the gas needed by the average family.
PopularScience_19310501_0118_005_0128.xml
article
68
68
NEW PROCESSES AND INVENTIONS
[no value]
NEW MACHINE BORES HOLE UNDER STREET
[no value]
[no value]
[no value]
[no value]
A MACHINE, invented by a California engineer, bores horizontal holes for pipes under streets. Operated by compressed air, it can dig small tunnels as long as forty feet from the starting point at one setting of the device under working conditions.
PopularScience_19310501_0118_005_0129.xml
article
68
68
AUTOMOBILES
[no value]
TEXAS BUMPS CONTROL FAST CAR DRIVERS
[no value]
[no value]
[no value]
[no value]
A SERIES of bumps, about a foot high, extending across streets at intervals, is solving the speed problem in the residential section of Fort Sam Houston, Texas. Traffic rules set a speed limit of twelve miles per hour. Serious violation of this limit is prevented by the series of bumps, recently installed, which make fast driving uncomfortable and dangerous.
PopularScience_19310501_0118_005_0130.xml
article
68
68
NEW PROCESSES AND INVENTIONS
[no value]
WALL PAPER CLEANS LIKE FLAT PAINT
[no value]
[no value]
[no value]
[no value]
SOAP and water won’t hurt a new washable wall paper coated with a cellulose material developed in the laboratories of the Du Pont company. Samples of this paper resisted 8,640 rubbings with cheese-cloth, soap, and water before showing signs of wear.
PopularScience_19310501_0118_005_0131.xml
article
68
68
HEALTH AND HYGIENE
[no value]
WHY SAVAGES ARE HEALTHY
[no value]
[no value]
[no value]
[no value]
HAVE you ever wondered how savages living under insanitary conditions, with no knowledge of diet, keep healthy? Carl van Noorden, Viennese doctor, believes it may be due to two factors —sparing use of salt and unfertilized cultivation of the vegetables they eat.
PopularScience_19310501_0118_005_0132.xml
article
69
69
UNUSUAL FACTS AND IDEAS
[no value]
ELECTRICITY USED TO COAT MIRRORS
[no value]
[no value]
[no value]
[no value]
AT LAST a way to give scientific mirrors a durable coating has been discovered. Silvering them has always been a problem, since the shiny coat must be on the front of the glass—unlike that of a boudoir mirror—and consequently is exposed to the air’s tarnishing effect.
PopularScience_19310501_0118_005_0133.xml
article
69
69
NEW PROCESSES AND INVENTIONS
[no value]
HEAD NET WITH WINDOW KEEPS MOSQUITOES OUT
[no value]
[no value]
[no value]
[no value]
FREE from annoyance by insect pests is the fisherman who dons a new head net. Unmindful of them, he can tramp through the most mosquito-infested marshes; nor can gnats and black flies and other insects get at his face. The net fits over any hat, and is attached to a collapsible steel frame.
PopularScience_19310501_0118_005_0134.xml
article
69
69
UNUSUAL FACTS AND IDEAS
[no value]
GIANT GRINDER FAIRLY EATS METAL
[no value]
[no value]
[no value]
[no value]
A GIANT among grinding machines was completed the other day by a tool manufacturing firm in Worcester, Mass. It is said to be the largest machine of its kind in the world. Comparison with the man in the photo gives an idea of its size. Huge steel or iron rods, as large as three feet in diameter and twenty feet long, can be handled on it.
PopularScience_19310501_0118_005_0135.xml
article
69
69
NEW PROCESSES AND INVENTIONS
[no value]
NEW PORTABLE FILTER INSURES CLEAN WATER
[no value]
[no value]
[no value]
[no value]
CAMPERS or tourists may get clean water almost anywhere by using a small filter developed recently by a Chicago, Ill., firm. The filter, to which a length of rubber tubing is attached, fits over the necks of one-gallon or two-gallon bottles.
PopularScience_19310501_0118_005_0136.xml
article
70
70
NEW PROCESSES AND INVENTIONS
[no value]
ELECTRIC HOTBED HEATER RUNS ITSELF
[no value]
[no value]
[no value]
[no value]
A DEVICE recently placed on the market by a Detroit, Mich., manufacturer, is an electric heater for hotbed sections in greenhouses. It resembles a steel bed spring, since it consists of a light angle-bar frame across which the heating elements are stretched.
PopularScience_19310501_0118_005_0137.xml
article
70
70
AVIATION
[no value]
GIANT SEAPLANE DO-X LIFTS FIFTY-FIVE TONS
[no value]
[no value]
[no value]
[no value]
ON ITS much-delayed way toward South America from Germany, the giant German seaplane DO-X recently set a new world’s record for heavier-than-air machines. In a test flight it lifted a total load of fifty-five tons into the air.
PopularScience_19310501_0118_005_0138.xml
article
70
70
NEW PROCESSES AND INVENTIONS
[no value]
ENGLISH PHONOGRAPH PLAYS UPSIDE DOWN
[no value]
[no value]
[no value]
[no value]
A NEW British phonograph plays records at any angle. It is fitted with a specially-balanced tone arm that remains in contact with the record regardless of how the machine is tilted—even upside down. Taking phonographs out in small boats, cars, and airplanes made necessary this acrobat among talking machines.
PopularScience_19310501_0118_005_0139.xml
article
70
70
AVIATION
[no value]
LIFE-SAVER CLAD IN ASBESTOS SUIT
[no value]
[no value]
[no value]
[no value]
ODDEST - costumed man aboard each of the naval aircraft carriers Saratoga and Lexington during recent maneuvers off Panama was a figure clad in asbestos. He dared not remove gloves or helmet for a second. He watched planes leaving and alighting on the decks.
PopularScience_19310501_0118_005_0140.xml
article
70
70
NEW PROCESSES AND INVENTIONS
[no value]
BALL-TIRE MOTOR BIKE WHEEL SKIDS SAFELY
[no value]
[no value]
[no value]
[no value]
A NOVEL rear wheel enables a British motorcycle race driver to skid his machine around turns on dirt tracks. It has a grooved rim that carries a series of balls free to rotate on small axles. The device is like a large ball bearing, except that the balls rotate at an angle to the direction of the wheel moving forward over the ground.
PopularScience_19310501_0118_005_0141.xml
article
70
70
NEW PROCESSES AND INVENTIONS
[no value]
EDUCATED DISK GIVES DATA ABOUT NATIONS
[no value]
[no value]
[no value]
[no value]
THIS disk shows at a glance all of the salient points regarding the nations of Europe. By setting the pointer opposite the country about which information is desired, the disk shows the name and population of the capital city, the location of the country in Europe, the area in square miles, the population per square mile, the population of the country, the form of government, the name and length of the principal river, the name and height of the highest mountain, the standard time when it is noon in Greenwich, and the national colors.
PopularScience_19310501_0118_005_0142.xml
article
70
70
ASTRONOMY
[no value]
STUDIES SUN’S CORONA FROM MOUNTAIN TOP
[no value]
[no value]
[no value]
[no value]
ASTRONOMERS travel thousands of miles to observe the sun’s luminous halo, or “corona,” during a total eclipse, the only time when it may be seen by human eyes. But a French astronomer, B. Lyot, has now successfully tested on a mountain peak in southern France a way to trace the form of the corona without waiting for an eclipse.
PopularScience_19310501_0118_005_0143.xml
article
71
71
AVIATION
[no value]
Pilotless Plane to Tour Country
[no value]
[no value]
[no value]
[no value]
A MODERN marvel of radio engineering—an airplane without a pilot, steered and controlled entirely by radio—is scheduled to start next month from Texas on a tour of 100 principal cities of the United States. POPULAR SCIENCE MONTHLY presents to its readers on this page the first published story and pictures of this radio wonder, which has hitherto been tested and flown in strictest secrecy.
PopularScience_19310501_0118_005_0144.xml
article
72
72
UNUSUAL FACTS AND IDEAS
[no value]
CRADLE FOR SICK HORSE MAKES TREATMENT EASY
[no value]
[no value]
[no value]
[no value]
TO AID a veterinary surgeon operate upon a sick horse, a unique revolving cradlelike operating table was recently installed at a “horse sanatorium" of Hoppegarten, near Berlin, Germany. After a small injection of a narcotic to make him manageable, the horse is strapped in the special harness provided.
PopularScience_19310501_0118_005_0145.xml
article
72
72
UNUSUAL FACTS AND IDEAS
[no value]
PAPER NOW MADE FROM TREE COMMON IN SOUTH
[no value]
[no value]
[no value]
[no value]
DR. CHARLES HERTY, former president of the American Chemical Society, announced recently that “slash pine,” a tree with which the South abounds, may become a crop rivaling cotton in importance, following the discovery that it can be made into white paper and newsprint.
PopularScience_19310501_0118_005_0146.xml
article
72
72
NEW PROCESSES AND INVENTIONS
[no value]
NEW EYE MASK SHIELDS SLEEPER FROM LIGHT
[no value]
[no value]
[no value]
[no value]
THAT rarest aid to restless sleepers— a really dark room—is brought within the reach of everyone by a new “sleep mask” designed especially for the purpose of shading a sleeper’s eyes. Padded with soft down, it fits lightly and comfortably over the face.
PopularScience_19310501_0118_005_0147.xml
article
72
72
NEW PROCESSES AND INVENTIONS
[no value]
TWO-PIECE ROWBOAT FITS BACK OF CAR
[no value]
[no value]
[no value]
[no value]
A NEW rowboat comes in halves, so that it can be stowed away easily for carrying on the back of a car. Arriving at the water’s edge, the owner has merely to join the halves together to have a full-sized, seaworthy sport boat. No special water-tight fitting is required, since each half is complete and able to float by itself.
PopularScience_19310501_0118_005_0148.xml
article
72
72
NEW PROCESSES AND INVENTIONS
[no value]
PANCAKES FLIPPED OVER BY AUTOMATIC COOKER
[no value]
[no value]
[no value]
[no value]
DESIGNED to take the place of human cooks, an automatic pancake cooker, recently invented, flips the cakes automatically. When its electric switches are turned on, a measured quantity of batter flows into the pan. At the end of an interval timed for proper cooking, the half-cooked pancake is deposited on its opposite side, on another cooking plate.
PopularScience_19310501_0118_005_0149.xml
article
73
73
NEW PROCESSES AND INVENTIONS
[no value]
DESIGNS NEW BRACKET FOR WINDOW SHADES
[no value]
[no value]
[no value]
[no value]
Two small openings shaped like markings on cards of the “heart” suit enable a new window shade roller bracket to be used at either end of the roller. The smaller of the openings holds the projections on the ends of the roller. These are passed through the jaws that connect the openings. Putting up shades on these brackets is said to be easier than when one closed-jaw bracket is used to hold the “fixed” end of the roller. According to the inventor, the bracket can be used with any type roller.
PopularScience_19310501_0118_005_0150.xml
article
73
73
NEW PROCESSES AND INVENTIONS
[no value]
STREET OR RAIL CAR CARRIES FREIGHT
[no value]
[no value]
[no value]
[no value]
LAST month a British passenger vehicle that can travel on road or rails, known as the “Ro-Railer,” was described in POPULAR SCIENCE MONTHLY. So successful were the first tests of this extraordinary gasoline motor car that a new type, the “Freight Ro-Railer,” has now appeared.
PopularScience_19310501_0118_005_0151.xml
article
73
73
UNUSUAL FACTS AND IDEAS
[no value]
RED SQUILL RAT POISON WON'T HURT CHILDREN
[no value]
[no value]
[no value]
[no value]
FATAL to rats or mice, but harmless to humans and cats and dogs, a new rat poison was developed recently by the United States Department of Agriculture. It is made by grinding bulbs of the red squill, an onionlike ornamental plant found along the shores of the Mediterranean.
PopularScience_19310501_0118_005_0152.xml
article
73
73
UNUSUAL FACTS AND IDEAS
[no value]
USE SHIP'S SMOKESTACK AS SMOKING ROOM
[no value]
[no value]
[no value]
[no value]
A HUGE transatlantic passenger liner was equipped recently with a novelty in the way of officers’ quarters. A smoking room is built into its forward smokestack. Since it is a motor vessel, its funnels are dummies. Their great size, however, enables their interiors to be used to good advantage.
PopularScience_19310501_0118_005_0153.xml
article
74
74
UNUSUAL FACTS AND IDEAS
[no value]
TYPEWRITER HAS FOUR-FOOT CARRIAGE
[no value]
[no value]
[no value]
[no value]
How would you like to use a typewriter like this one every day? Said to be the largest in the world, it was not designed for correspondence work, but was developed to handle forms and wide ledgers required by some steamship and insurance companies.
PopularScience_19310501_0118_005_0154.xml
article
74
74
AVIATION
[no value]
NOSE HANGAR KEEPS PLANE FROM FREEZING
[no value]
[no value]
[no value]
[no value]
“NOSE hangars,” which protect airplane engines from subzero weather, have been put in service in Canada. Stoves in the hangars send heated air around the motors, keeping them from freezing. Folding wings on the plane enable it to tuck its nose easily into such a shelter.
PopularScience_19310501_0118_005_0155.xml
article
74
74
AVIATION
[no value]
ARMY AIDS “FLYING WEATHER” FORECASTS
[no value]
[no value]
[no value]
[no value]
WITHIN the last few months, “flying weather” predictions have appeared in newspapers. Where they come from is shown in this picture, made at Mitchel Field, N. Y. Here and at other fields, small balloons are released periodically. Observers watch their drift with theodolites, or measuring telescopes, to find the velocity of high-altitude winds.
PopularScience_19310501_0118_005_0156.xml
article
74
74
AVIATION
[no value]
NEWARK AIRPORT LEADS ALL OTHERS IN TRAFFIC
[no value]
[no value]
[no value]
[no value]
THE airport at Newark, N. J., terminus of transcontinental air routes and hub of coastal air lines in the East, is now the busiest in the world. Fifty passenger planes, each bearing six to eighteen passengers, land or take off each day, and twelve mail planes arrive or leave nightly.
PopularScience_19310501_0118_005_0157.xml
article
74
74
UNUSUAL FACTS AND IDEAS
[no value]
WAR-TIME DEVICE TO SAVE MINERS
[no value]
[no value]
[no value]
[no value]
A DEVICE developed in the World War to detect enemy tunneling or “sapping” may safeguard coal miners from one of their strangest hazards. Occasionally underground pockets of gas, compressed under high pressure and tightly sealed by Nature, are found near coal mines.
PopularScience_19310501_0118_005_0158.xml
article
74
74
MODELS
[no value]
ONE-OUNCE LOCOMOTIVE SMALLEST IN WORLD
[no value]
[no value]
[no value]
[no value]
A ONE-OUNCE locomotive recently shown in London seems to justify its builder’s assertion that it is the smallest one in the world. Leonard Beal, a musician of Hampstead, England, built the tiny locomotive. Though but two inches long, it is an exact miniature of a light side-tank locomotive, a type used for short suburban runs in Great Britain.
PopularScience_19310501_0118_005_0159.xml
article
75
75
AVIATION
[no value]
NEW HOOD AIDS PILOT IN BLIND FLYING
[no value]
[no value]
[no value]
[no value]
DANGERS of blind, or instrument, flying experiments are eliminated by a new type of hood, just constructed by two Brooks Field, Texas, engineers. It snaps open at the release of a trigger, enabling the flyer to climb out and free himself in his parachute in the event of a fall.
PopularScience_19310501_0118_005_0160.xml
article
75
75
UNUSUAL FACTS AND IDEAS
[no value]
AIR-DRIVEN RAILWAY CAR FASTEST YET
[no value]
[no value]
[no value]
[no value]
A RAILWAY car designed by Professor Wiesinger, head of a technical school in Zurich, Switzerland, is believed to be capable of speeds of 225 miles an hour in daily operation with 150 passengers. The designer constructed a small scale model of his unusual looking vehicle, fully streamlined and fitted with aerial propellers at each end.
PopularScience_19310501_0118_005_0161.xml
article
75
75
UNUSUAL FACTS AND IDEAS
[no value]
FIRST FLORISTS' CLASS
[no value]
[no value]
[no value]
[no value]
WHAT is said to be the first school for florists as a part of a public school system is in operation in St. Louis, Mo. Classes are held two evenings a week and students are taught designing, window trimming, and color harmony.
PopularScience_19310501_0118_005_0162.xml
article
75
75
NEW PROCESSES AND INVENTIONS
[no value]
TYPEWRITER COUNTS WORDS AS WRITTEN
[no value]
[no value]
[no value]
[no value]
Now you can tell the length of a story or letter as you type it. A little device that counts words written by typewriters is the product of a firm of instrument makers in Hartford, Conn. It is operated from the space bar. Every time you depress it after writing a word, the device tallies up a word for you.
PopularScience_19310501_0118_005_0163.xml
article
75
75
UNUSUAL FACTS AND IDEAS
[no value]
OFFICE BUILDING HAS GLASS WALLS
[no value]
[no value]
[no value]
[no value]
WITH outer walls made almost entirely of glass and steel, this office building represents a new trend in architecture. Windows are set in light steel frames and extend from floor to ceiling. Since the framework has been reduced to a minimum, the effect is that of an almost solid glass wall.
PopularScience_19310501_0118_005_0164.xml
article
75
75
ENGINEERING
[no value]
STEAM HEAT AIDS BRIDGE BUILDERS
[no value]
[no value]
[no value]
[no value]
BUILDING a concrete bridge in winter was the problem that highway engineers of Lansing, Mich., recently faced. They solved it by constructing a steam-heated house over the entire length of the bridge site. This enabled them to pour concrete in weather that was frequently below zero.
PopularScience_19310501_0118_005_0165.xml
article
76
76,77,130
The Architect Builds His Own Home—A Series Simplicity Adds Beauty to House
[no value]
The Architect Builds His Own Home—A Series Simplicity Adds Beauty to House
[no value]
[no value]
[no value]
GEORGE WILLIAM TEARE
IF SOMEONE were to ask me what was the most difficult commission I have thus far had, I should answer at once: “That of designing and building the house in which my family and I were to live.” Perhaps the reason for that difficulty lies in the fact that, in planning and designing homes for others, there come to the architect's mind all the unique features that have been involved in making each particular job a little different from the rest.
PopularScience_19310501_0118_005_0166.xml
article
78
78,79
NEW DEVICES FOR THE HOME
[no value]
Novel Household Inventions
[no value]
[no value]
[no value]
[no value]
MOP THAT CAN’T MAR. It is impossible for this unusual mop to scratch floors or woodwork, as no stick or metal part projects beyond the threads of which it is made. The head is fastened right on the end of the stick by an ingenious arrangement of staples as illustrated in the photograph above.
PopularScience_19310501_0118_005_0167.xml
article
80
80
Editorials
[no value]
Editorials
Radio Rackets
[no value]
[no value]
[no value]
THE air is surcharged with hokum. The wonderful radio networks, described in these pages last month, are used by a small army of fakers as webs in which to catch the unwary. Nowadays, every receiving set is a trap for the gullible. The turn of a knob, almost any hour of the day or night, will bring you the voice of an astrologer warning you not to get married while the moon is waning.
PopularScience_19310501_0118_005_0168.xml
article
81
81
HELPFUL HINTS FOR RADIO FANS
[no value]
Tiny Condenser for Set Builder
NEW TEST POINTS
USE OF BATTERY TUBES
A B C's of Radio
HEAT AND TROUBLE
[no value]
[no value]
[no value]
IN BUILDING any type of portable radio receiver, the limiting factor is the size of the individual parts. Fortunately tuning coils can be wound of fine wire on small diameter coil forms without seriously impairing their efficiency.
PopularScience_19310501_0118_005_0169.xml
article
82
82,83,135
Radio’s Mystery Waves Explained
[no value]
Radio’s Mystery Waves Explained
Special Apparatus Needed if You Want to Hear Short Wave Vibrations that Carry Long Distance Broadcasts
[no value]
[no value]
ALFRED P. LANE
IN THE average radio fan’s mind, the words “short wave radio” conjure up thoughts of unbelievably long distance reception, queer apparatus, and unusual complications. An atmosphere of mystery surrounds the whole subject. As a matter of fact short wave transmission is just one branch of radio and is no more complicated or difficult to understand than ordinary broadcasting.
PopularScience_19310501_0118_005_0170.xml
article
84
84,128
Should Law Scrap Old Cars?
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Should Law Scrap Old Cars?
An Auto Is As Old As It Acts, Says Gus, and You Can Keep It Young by Proper Repairs MARTIN BUNN
Gus Says:
COUNTERFEITING KNOWN TO ROMAN CROOKS
WALKING STICK LIGHTS AS END HITS GROUND
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[no value]
[no value]
GUS WILSON, half owner of the Model Garage, had about decided to call it a day when his partner Joe Clark called him to the window. “What’s the idea of the funny decorations?” Joe asked, pointing to a small sedan that was coming slowly down the road.
PopularScience_19310501_0118_005_0171.xml
article
85
85,86
THE HOME WORKSHOP
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Prizes for Match Stick Models
Here is a brand-new and amusing pastime that you’ll really enjoy—and a chance to win one of eighteen cash awards
$100 in Cash Prizes
Prizes for Photographs
[no value]
[no value]
[no value]
WHAT can you whittle from a single match stick? To find out, POPULAR SCIENCE MONTHLY is offering prizes amounting to $100 in all. A list of the prizes and the rules of the contest are given on page 86. With two exceptions, the prizes will be awarded for human figures, animals, or other objects or models made, in each case, from a single large wooden match stick of the common kitchen variety that can be struck anywhere.
PopularScience_19310501_0118_005_0172.xml
article
87
87
MODELS
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Simplified Plans for Making a Model of The World's Fastest Racing Auto
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[no value]
DONALD W. CLARK
BECAUSE of its extraordinary design and almost incredible speed, Sir Malcolm Campbell’s latest stream-lined racer Bluebird II is a timely and interesting subject for the model maker. Streaking across the smooth sand at Daytona Beach, Florida, this car recently attained a speed of 245 miles an hour, winning for Sir Malcolm the world’s automobile speed record (P.S.M., Apr. ’31, p. 32).
PopularScience_19310501_0118_005_0173.xml
article
88
88,89
CRAFTWORK
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A Trick Folding Cigarette Box
All you have to do is to pull open a small drawer, and a novel three-piece rack automatically appears like magic
How to Take Better Photographs
[no value]
[no value]
WALTER E. BURTON
CONTAINING thirty cigarettes, four ash trays, a lighter or box of safety matches, and a little brass statue or “stomper” used to press the life out of glowing butts, this novelty box adds to the attractiveness of any smoker’s table. Furthermore, it measures only 4⅛ by 4½ by 7¾ in.; and it contains mechanical features that make it as interesting to operate as a toy.
PopularScience_19310501_0118_005_0174.xml
article
90
90,91
CRAFTWORK
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Making a Magic Skin Tea Tray
There’s a famous story connected with it which you can tell to amuse your friends
[no value]
[no value]
CHARLES H. ALDER
IN BALZAC’S famous tale, The Magic Skin, there is a description of the hide of a wild ass on which appeared in mysterious Sanskrit characters, as if inlaid, the following legend: Possessing me thou shalt possess all things. But thy life is mine, for God has so willed it.
PopularScience_19310501_0118_005_0175.xml
article
91
91,92
MODELS
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How to Modelize Fort Union
Clarence E. Mulford brings to life a great trading post of the Old West and introduces a novelty for model makers
[no value]
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PERHAPS only the zealous history hound, hard-bitten by the romance of the West in the interval between Manual Lisa's first expedition up the Missouri River in search of furs and the dying out of the great western cattle trail, might be expected to find Fort Union a fit subject for model making.
PopularScience_19310501_0118_005_0176.xml
article
92
92
ASTRONOMY
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THIS PORTABLE TELESCOPE COST $15
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DON H. JOHNSTON
ONE observation of Saturn with its beautiful ring system would repay anyone who is astronomically inclined for the slight expense and work necessary to construct this portable telescope outfit. The telescope, which was purchased new for $13.98, has a 2-in. objective; with a celestial eyepiece, it gives a magnification of sixty-eight diameters.
PopularScience_19310501_0118_005_0177.xml
article
92
92,110
IDEAS FOR THE HANDY MAN
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BLUEPRINTS FOR YOUR HOME WORKSHOP
Other Western Models
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[no value]
[no value]
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.
PopularScience_19310501_0118_005_0178.xml
article
93
93
CRAFTWORK
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After a dusty trip you can spruce up quickly with this Leather Covered Whisk Broom and Shoe Polishing Kit
[no value]
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[no value]
F. CLARKE HUGHES
THIS combined dustbrush and shoe polisher will appeal to every traveler and motorist. It is, indeed, an almost indispensable article. After a drive in the country, both brush and polisher are always useful; and in this compact form they take up so little room that they can be carried in the pocket of one of the automobile doors or in a corner of even the most crowded traveling bag.
PopularScience_19310501_0118_005_0179.xml
article
94
94,95
IDEAS FOR THE HANDY MAN
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How to Grind and Hone Your Wood Turning Tools
Pointers on the care of a lathe and on the best way to center the work
[no value]
[no value]
W. CLYDE LAMMEY
MANY excellent small wood turning lathes are now available. They may be classified roughly into two divisions, depending upon the way in which they are driven. One type has a cone or step pulley on the headstock and is driven by means of a belt from a similar pulley mounted on a countershaft, which, in turn, is driven by a motor or engine.
PopularScience_19310501_0118_005_0180.xml
article
96
96
Ideas of Value to Car Workers
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Ideas of Value to Car Workers
Mechanical Assistant Helps in Taking Nuts from Oil Pan Bolts—Mica Tests Plugs for Internal Shorts
[no value]
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AS IT is impossible on most cars for one man to reach both the bolts and the nuts on the oil pan from one position, it is common practice to have an assistant remove the pan. Figure 3, at right, shows how to make a mechanical assistant. The counterweight at the end of bar B holds the socket wrench in place and a properly placed foot will keep it from turning.
PopularScience_19310501_0118_005_0181.xml
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97
97
[no value]
[no value]
HENRY DISSTON & SONS, Inc.
[no value]
HENRY DISSTON & SONS, Inc.
[no value]
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PopularScience_19310501_0118_005_0182.xml
article
98
98,100
HINTS FOR THE MECHANIC
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Hints on Salvaging High-Speed Tools
How to reduce costs in the small shop by reclaiming worn or damaged cutters
[no value]
[no value]
HECTOR J. CHAMBERLAND
VALUABLE high-speed tools often are discarded in the small machine shop long before their useful life is over. They could be salvaged at a fraction of the cost of providing new tools; and in any large manufacturing plant where a careful study is made of all ways to reduce waste, they would be restored to usefulness.
PopularScience_19310501_0118_005_0183.xml
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99
99
[no value]
[no value]
THE L. S. STARRETT CO.
[no value]
THE L. S. STARRETT CO.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0184.xml
article
100
100
HINTS FOR THE MECHANIC
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Old Bill Says—
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SPIRALLY fluted taper pin reamers should never be run at a speed greater than two thirds of the proper speed for a drill of the same diameter. A discarded hack saw blade, ground to a knife edge and inserted in a hack saw frame, forms an excellent knife for cutting rubber.
PopularScience_19310501_0118_005_0185.xml
advertisement
101
101
[no value]
[no value]
Brown & Sharpe Mfg. Co.
[no value]
Brown & Sharpe Mfg. Co.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0186.xml
article
102
102
HINTS FOR THE MECHANIC
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Six Machine Shop Timesavers
How to start taps, extend parallel clamps, and fasten down machinery—A center gage and a handy drill case
STARTING TAPS STRAIGHT
HOLDING DOWN MACHINES
CENTER ALIGNMENT GAGE
DRILL AND TAP CASE
[no value]
[no value]
HARRY MOORE
CLARENCE J. TURCOTTE
CHRIS N. SCOTT
F. J. WILHELM
CHARLES H. WILLEY
CARL O. LANDRUM
WHEN a machinist’s parallel clamp will not open wide enough to take the work at hand, it sometimes can be made to serve by using with it one jaw and both screws from another similar clamp in the manner illustrated in Fig. 1. Open the complete clamp to its full extent, allowing the front screw to enter only halfway through the threaded hole in the jaw and then start the front screw of the single jaw into the other end of this same hole.
PopularScience_19310501_0118_005_0187.xml
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103
103
[no value]
[no value]
THE LUFKIN RULE CO.
[no value]
THE LUFKIN RULE CO.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0188.xml
article
104
104
IDEAS FOR THE HANDY MAN
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A Better Way to Sprinkle Lawns
How to install an underground watering system that rivals rain in its efficiency
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[no value]
B. M. BEEMAN
HOW often have you wished for an underground sprinkler system with which you could water your entire lawn by a turn of the wrist? A well-designed system of this kind is rain’s only rival; it provides a fine mist that gathers on the bushes, flowers, and lawn like dew.
PopularScience_19310501_0118_005_0189.xml
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105
105
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[no value]
Popular Science Publishing Co.
[no value]
Popular Science Publishing Co.
[no value]
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[no value]
PopularScience_19310501_0118_005_0190.xml
article
106
106,107
FOR THE HOME OWNER
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What Floor Finish Shall I Use?
Chart Showing How to Finish Old and New Floors
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[no value]
BERTHA A. HOUCK
WHEN you are selecting the finish for your floor, three things must be taken into consideration—the type of room, the condition of the floor, and the kind of wood from which it is made. The more formal room ordinarily has stained and varnished floors, the exception to this being in a strictly “period” house.
PopularScience_19310501_0118_005_0191.xml
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107
107
[no value]
[no value]
NORTH BROS. MFG. CO.
[no value]
NORTH BROS. MFG. CO.
[no value]
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PopularScience_19310501_0118_005_0192.xml
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108
108
[no value]
[no value]
Motor Improvements Inc.
[no value]
Motor Improvements Inc.
[no value]
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PopularScience_19310501_0118_005_0193.xml
article
108
108,109
IDEAS FOR THE HANDY MAN
[no value]
This Mirror Turns Magically into a Lighted Photo
[no value]
[no value]
[no value]
JOHN WORKLEY
TO ALL appearances, this mirror is nothing out of the ordinary; it reflects your face like any other glass. But turn on the electric light concealed at the back, and it is no longer a mirror. Instead, it is a photograph beautifully illumined by the soft radiance from behind.
PopularScience_19310501_0118_005_0194.xml
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109
109
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[no value]
E. C. ATKINS and Company
[no value]
E. C. ATKINS and Company
[no value]
[no value]
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PopularScience_19310501_0118_005_0195.xml
advertisement
110
110
[no value]
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NICHOLSON FILE CO.
[no value]
NICHOLSON FILE CO.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0196.xml
article
111
111
FOR THE HOME OWNER
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WOODEN GUIDE AIDS IN EDGING GRASS PLOTS
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ROBERT W. MINER
WHEN the edge of a lawn is to be trimmed along a sidewalk or drive-way, it is common practice to stretch a rope to serve as a guide. A better method is to use a board 10 or 12 ft. long, as illustrated. This is prepared by snapping a chalk line along one edge and planing it straight.
PopularScience_19310501_0118_005_0197.xml
article
111
111
FOR THE HOME OWNER
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NEAT ICE PICK HOLDER MADE FROM PENCIL
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[no value]
[no value]
F. J. WILHELM
THE discarded shell or body of a mechanical lead pencil will serve as a holder for a small ice pick. It may be attached to the wall in any convenient position near the refrigerator by means of two screw eyes, one large enough to slip over the body and the other of a size to fit the tapered nose about halfway up.
PopularScience_19310501_0118_005_0198.xml
advertisement
111
111
[no value]
[no value]
The R. K. LeBlond Machine Tool Co.
[no value]
The R. K. LeBlond Machine Tool Co.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0199.xml
advertisement
112
112
[no value]
[no value]
INDIAN MOTOCYCLE CO.
[no value]
INDIAN MOTOCYCLE CO.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0200.xml
article
112
112
IDEAS FOR THE HANDY MAN
[no value]
HOW TO MAKE A SIMPLE CUT-STRING PUZZLE
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[no value]
RICHARD L. GRAVES
SIMPLE as it is to make, the trick or puzzle illustrated is quite deceiving and can be passed around for inspection. First, you show the blocks of wood closed and pull the string back and forth to demonstrate that it is a continuous length. Then you ask someone to run the blade of a penknife between the blocks so as to cut the string.
PopularScience_19310501_0118_005_0201.xml
article
113
113
FOR THE HOME OWNER
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PUNCH AND GAGE FOR PLANTING HEDGES
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E. MOFFAT
THE plant-hole punch, depth gage, and spacer illustrated is a timesaving tool for setting out a number of small plants such as required for a hedge. It is merely a piece of wood 2 by 2 by 16 in. with two guides nailed on the sides 2 or 3 in. from the end to gage the depth of the holes.
PopularScience_19310501_0118_005_0202.xml
article
113
113
IDEAS FOR THE HANDY MAN
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HINTS ON REPAINTING OLD GOLF BALLS
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[no value]
G. W.
WHILE repainted golf balls may not be as lively as new ones, many golfers find them good enough for practice. First, the balls must be thoroughly cleaned by scrubbing them with a stiff brush in warm water and soap. In applying the enamel, which should be the special golf ball enamel obtainable at sporting goods stores, pour a small amount into the palm of the left hand, place the ball in it, and place the right hand over the ball.
PopularScience_19310501_0118_005_0203.xml
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113
113
[no value]
[no value]
Eastman Kodak Company
[no value]
Eastman Kodak Company
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0204.xml
article
114
114
IDEAS FOR THE HANDY MAN
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Home Chemistry Table Rests upon Stationary Tubs
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[no value]
[no value]
J. I. KINMAN
MANY readers of POPULAR SCIENCE MONTHLY, judging from my own experience, would take up the useful and most entertaining subject of home chemistry as a hobby if only they had a convenient place to work and do their experimenting. In my own case, the problem of arranging for a suitable table near running water kept me from entering into this work in the way I desired for three or four years.
PopularScience_19310501_0118_005_0205.xml
article
114
114
MODELS
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SMALL SANDING DISKS SHAPE MODEL PARTS
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[no value]
HARRY F. LOWE
FOR the delicate shaping of model parts, small sanding disks often can be used to advantage. For example, the spokes of the covered wagon model shown in POPULAR SCIENCE MONTHLY Blueprints Nos. 118, 119, and 120 (see page 110) require arc-shaped depressions or “flats” to be formed just outside the hub line. On my model I made these with a ½ in. thick wooden disk of suitable diameter, to the edge of which a strip of sandpaper was fastened.
PopularScience_19310501_0118_005_0206.xml
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114
114
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Advertisement
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PopularScience_19310501_0118_005_0207.xml
article
115
115
IDEAS FOR THE HANDY MAN
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Ring-the-Peg Game Is Easy to Build
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[no value]
[no value]
D. W. C.
HERE is a little game that will amuse any small boy. It is so simple that he can make it himself in less than two hours, since all it consists of are five wooden pegs or dowels of various lengths set into a base ¾ by 6 by 24 in. The pegs are spaced as shown in the drawings and set into the base ⅝ in.
PopularScience_19310501_0118_005_0208.xml
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115
115
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[no value]
The Casein Mfg. Co.
[no value]
The Casein Mfg. Co.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0209.xml
article
116
116,117,118
CRAFTWORK
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Building a Backgammon Table Fit for Championship Play
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[no value]
R. EUGENE DOWNER
WITH backgammon enjoying its present extraordinary popularity, no amateur woodworker has far to look for a project upon which to demonstrate his skill. All he has to do is to build an inlaid backgammon table. While not an especially difficult task, it will reward him with more favorable comments and reflect greater credit upon his craftsmanship than almost any other piece of furniture he could construct.
PopularScience_19310501_0118_005_0210.xml
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116
116
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Goodell-Pratt Company
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Goodell-Pratt Company
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PopularScience_19310501_0118_005_0211.xml
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117
117
[no value]
[no value]
AMERICAN SCREW CO.
[no value]
AMERICAN SCREW CO.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0212.xml
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117
117
[no value]
[no value]
THE RIDGE TOOL CO.
[no value]
THE RIDGE TOOL CO.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0213.xml
article
118
118,119
IDEAS FOR THE HANDY MAN
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TWELVE-ROOM HOME FOR MARTINS BUILT LIKE A FAIRY MANSION
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[no value]
[no value]
[no value]
THIS twelve-room bird house for martins has a wide roof which gives protection from rain as well as from the hot sun, and its base is wide enough to allow the young birds to stretch their wings and gain a little confidence before they fly. Another of its advantages is the ease with which it may be taken apart and cleaned.
PopularScience_19310501_0118_005_0214.xml
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118
118
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THE KENDALL COMPANY
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THE KENDALL COMPANY
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[no value]
[no value]
PopularScience_19310501_0118_005_0215.xml
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118
118
[no value]
[no value]
REMINGTON ARMS COMPANY, Inc.
[no value]
REMINGTON ARMS COMPANY, Inc.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0216.xml
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118
118
[no value]
[no value]
The AMERICAN FLOOR SURFACING MACHINE CO.
[no value]
The AMERICAN FLOOR SURFACING MACHINE CO.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0217.xml
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119
119
[no value]
[no value]
Advertisements
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[no value]
[no value]
PopularScience_19310501_0118_005_0218.xml
advertisement
120
120
[no value]
[no value]
Bridgeport Hdwe. Mfg. Corp.
[no value]
Bridgeport Hdwe. Mfg. Corp.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0219.xml
article
120
120
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[no value]
TAPESTRY SCREEN HIDES FIREPLACE OPENING
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[no value]
[no value]
B. G. S.
A SIMPLE yet attractive screen for hiding the fireplace opening during the warmer months when the fireplace is not used can be made by the home worker with little expenditure of time and money. The frame consists of two turned upright pieces (square ones may be substituted if the home worker does not have the use of a lathe), two small cross-pieces, four feet, and two pieces of dowel as long as the frame is wide.
PopularScience_19310501_0118_005_0220.xml
article
120
120
MODELS
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Interested in Building a Model Railroad?
[no value]
[no value]
[no value]
[no value]
IF YOU are, you undoubtedly wish POPULAR SCIENCE MONTHLY would publish more articles on model engineering. Please send your suggestions for such articles to the Home Workshop Editor. Specify what particular subjects you would enjoy most.
PopularScience_19310501_0118_005_0221.xml
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120
120
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[no value]
SAVOGRAN CO.
[no value]
SAVOGRAN CO.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0222.xml
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120
120
[no value]
[no value]
IDEAL AEROPLANE & SUPPLY COMPANY, Inc.
[no value]
IDEAL AEROPLANE & SUPPLY COMPANY, Inc.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0223.xml
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120
120
[no value]
[no value]
The Ship Model Society of Rhode Island
[no value]
The Ship Model Society of Rhode Island
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0224.xml
article
121
121
IDEAS FOR THE HANDY MAN
[no value]
Paraffin Safeguards Fragile Shipments
[no value]
[no value]
[no value]
W. LESLIE TODD
AMONG the native trinkets I brought home with me after a year’s residence in the Philippines was a small but perfect plaster cast of a carabao. In case of breakage it could not be replaced, since the original mold had been destroyed, and it was otherwise valuable to me, yet because of the ears, horns, tail, and slender legs—the latter integral with a heavy plaster base—the packing of it presented a puzzling problem.
PopularScience_19310501_0118_005_0225.xml
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121
121
[no value]
[no value]
The A. S. BOYLE CO.
[no value]
The A. S. BOYLE CO.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0226.xml
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121
121
[no value]
[no value]
L C Smith & Corona Typewriters Inc
[no value]
L C Smith & Corona Typewriters Inc
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0227.xml
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122
122
[no value]
[no value]
Advertisements
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[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0228.xml
advertisement
123
123
[no value]
[no value]
SMOOTH-ON MFG. CO.
[no value]
SMOOTH-ON MFG. CO.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0229.xml
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123
123
[no value]
[no value]
WALKER-TURNER CO., Inc.
[no value]
WALKER-TURNER CO., Inc.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0230.xml
advertisement
124
124
[no value]
[no value]
TWIST DRILL & MACHINE COMPANY
[no value]
TWIST DRILL & MACHINE COMPANY
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0231.xml
advertisement
124
124
[no value]
[no value]
HAMMARLUND MFG. CO.
[no value]
HAMMARLUND MFG. CO.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0232.xml
advertisement
124
124
[no value]
[no value]
Popular Science Publishing Co.
[no value]
Popular Science Publishing Co.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0233.xml
advertisement
125
125
[no value]
[no value]
Advertisements
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[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0234.xml
advertisement
126
126
[no value]
[no value]
Advertisements
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[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0235.xml
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127
127
[no value]
[no value]
Advertisements
[no value]
[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0236.xml
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128
128
[no value]
[no value]
Advertisements
[no value]
[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0237.xml
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129
129
[no value]
[no value]
COYNE ELECTRICAL SCHOOL
[no value]
COYNE ELECTRICAL SCHOOL
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0238.xml
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130
130
[no value]
[no value]
Advertisement
[no value]
[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0239.xml
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131
131
[no value]
[no value]
Coyne Electrical School
[no value]
Coyne Electrical School
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0240.xml
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132
132
[no value]
[no value]
Advertisement
[no value]
[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0241.xml
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132
132
[no value]
[no value]
Advertisement
[no value]
[no value]
[no value]
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PopularScience_19310501_0118_005_0242.xml
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133
133
[no value]
[no value]
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[no value]
[no value]
[no value]
[no value]
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PopularScience_19310501_0118_005_0243.xml
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134
134
[no value]
[no value]
American School
[no value]
American School
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0244.xml
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134
134
[no value]
[no value]
Advertisement
[no value]
[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0245.xml
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135
135
[no value]
[no value]
Advertisements
[no value]
[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0246.xml
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136
136
[no value]
[no value]
Advertisements
[no value]
[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0247.xml
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137
137
[no value]
[no value]
Advertisements
[no value]
[no value]
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0248.xml
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138
138
[no value]
[no value]
RCA INSTITUTES, Inc.
[no value]
RCA INSTITUTES, Inc.
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0249.xml
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139
139
[no value]
[no value]
Advertisement
[no value]
[no value]
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PopularScience_19310501_0118_005_0250.xml
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140
140
[no value]
[no value]
Advertisements
[no value]
[no value]
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PopularScience_19310501_0118_005_0251.xml
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141
141
[no value]
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Advertisements
[no value]
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PopularScience_19310501_0118_005_0252.xml
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142
142
[no value]
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Advertisements
[no value]
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PopularScience_19310501_0118_005_0253.xml
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143
143
[no value]
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[no value]
[no value]
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PopularScience_19310501_0118_005_0254.xml
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144
144
[no value]
[no value]
Ethyl Gasoline Corporation
[no value]
Ethyl Gasoline Corporation
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0255.xml
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145
145
[no value]
[no value]
THE J. B. WILLIAMS COMPANY
[no value]
THE J. B. WILLIAMS COMPANY
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0256.xml
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146
146,147,148
[no value]
[no value]
R. J. Reynolds Tobacco Company
[no value]
R. J. Reynolds Tobacco Company
[no value]
[no value]
[no value]
PopularScience_19310501_0118_005_0257.xml