Archive | August, 2012

The atomic age – as seen in 1941

31 Aug

I always used to imagine that, unless you were in the Manhattan Project, or a top military or political leader, that the atomic bomb had come as a great surprise and only after Hiroshima did the average public get to hear of the new nuclear physics. But nothing could be further from the truth. Not just the scientific papers, but magazines like “Popular Science” and “Popular Mechanics” (and, no doubt, many others) were often publishing suprising details about the progress in atomic physics.

This article comes from January 1941 Popular Mechanics Magazine (“written so you can understand it”) and, though wildly optimistic, is perfectly clear about U235 fission, with references to plutonium breeding and isotopic separation:

  • Author’s idea of what life may be like in Uranium age. Note that most activities are located underground – even farming. Only transportation and recreation are above the surface.

The Miracle of U-235

SEVERAL months ago you read in Popular Mechanics that the secret of atomic power is close to solution and that possibly within a decade civilization will be using the tremendous amounts of energy contained in U-235, an isotope of uranium.

Since then, additional research has opened up greater possibilities than ever. At first we thought that a heavy power plant weighing tons would be required to extract the power; now it appears that a pound or even a single ounce of U-235 can be made to deliver energy. A power plant the size of a typewriter will be available. Its heart will be a one-pound package of uranium that contains the same amount of power that we extract from 250,000 gallons of gasoline. With such a power pack in a car you could drive 5,000,000 miles without refueling. Obviously, at $1,000 a pound, U-235 will be cheap.

But more miles per dollar is only one minor advantage foreseen for the uranium age. We can look forward to universal comfort, practically free transportation, and unlimited supplies of materials. Power will be cheap in every home and factory, without distribution lines, and electricity will cost less than one-tenth of a cent per kilowatt-hour.

  • Dr Langer’s conception of the U-235 automobile

  • Author’s idea of U-235 plane, a flying wing with propelling jets at rear and lifting jets underneath.

Postponing explanations for awhile, it is pointed out that water passing over U-235 can be brought almost instantly to a very high temperature and a correspondingly high steam pressure. To utilize this property one need only take over the principle of the flash boiler. Water is passed through a small chamber which contains U-235 in porous form. The chamber may be less than six inches in diameter. The water emerges as high-pressure steam into a series of turbine wheels all solid to the same shaft. Speed depends on the rate at which the steam passes through. A reversing valve may be used to divert the steam flow to an opposite-turning turbine on the same shaft to obtain a braking or reversing action. Complete control is obtained by throttling down or opening up the water supply and exhaust to get less or more power at the same operating pressure.

The driving mechanism of the automobile is now clear. Under the body is a water tank that helps shield the occupants from radiations emitted by the uranium and also puts the center of gravity low. Each wheel hub has on it a very small reversible turbine motor such as the one described. This car needs no differential or clutch. The uranium must be detachable because it probably will outlast the car. Recovering its own exhaust steam, such a car could travel without stopping until it wore out its tires or needed other servicing. Using the newly developed vertical propellers, such a vehicle might be converted into a high-speed, long-range vessel to travel on water, and might be furnished with unfolding wings for travel through the air.

  • Aparatus for separating elements into their isotopes

Let’s study the process by which the fabulous amount of energy can be release from U-235. It is not a perpetual-motion scheme. It happens that U-235 is a special kind of uranium so near the point of it stability that any neutron entering breaks it down into entirely different out substances, such as bromine, iodine, barium, krypton, and many others. In the transmutation these products take on rapid motion which is soon transformed into heat. It would take a potential difference of a most 200,000,000 volts to duplicate the energy release. The burning of coal corresponds to about four volts on this scale, some 50,000,000 times feebler the the uranium reaction. The mechanism of our uranium motor is based on that reaction. A few neutrons are constantly being introduced, with the help of radium, into our small box of U-235. There is a regenerative feature that make the reaction continuous. Clever tricks are already known to prevent the process from getting out of hand.

Recently in California it has been learned that the ordinary uranium atoms sometimes can be transformed by neutrons into new atoms which can be split up to give the enormous energy of uranium-235. At Westinghouse it has been discovered that photons, which are like ordinary light but have higher energy, can start the energy chain in U-235. These two discoveries mean that in the process of breaking up U-235 and deriving its energy, the by-product photons and neutrons turn right around and manufacture new material to provide new energy. It is not inconceivable that in practice each U-235 atom that splits will cause a U-238 atom to be transformed into an energy-producing variety. Translating that into simple language, a pound of U-235 would be equivalent to 500,000 gallons of gasoline instead of 250,000 indicated above. At the same time the total equivalent supply of U-235 would be doubled and the things predicted in this article would become twice as easy to attain.

Only one atom in 140 uranium atoms is of the proper kind and the hitch at present is that we haven’t found the most practical method for separating these special U-235 atoms from the rest of the uranium. This is similar to many problems that have been solved in the past, and solution of the problem is foreseen.

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Choosing a shovel

30 Aug

Such a simple thing, but small differences between one shovel and another can make a big difference to the effort required. I recommend shovelling earthquake liquifaction for an instant lesson in the subject.  This summary comes from an article on shovelling, in October 1961’s Popular Science:

The Right Shovel for the Job


A shovel’s “lift” is the angle that the handle makes with the blade. The higher the lift, the sharper the angle. For digging, you want low lift so you can press the blade straight into the ground and still grasp the handle comfortably. A high-lift handle forces you to lean too far forward, throws you off balance, and tires you. For shoveling, such as spreading earth, sand, gravel, and other materials, you want a high-lift handle so you can slide the blade flat along the ground without stooping.

To check for lift, hold the shovel’s blade flat against the floor with your foot and measure the distance from the handle tip to the floor. For digging, this should be no more than 22″ (560mm) for long handled shovels of about 58″ (1500mm). For shoveling, you want at least 32″  (800mm) to put the handle at a comfortable height.

  • Check for “LIFT” by measuring distance from handle tip to floor with blade held flat. It should be at least 32″ (800mm) for a good high-lift shovel, no more than 22″ (560mm) for a low-lift type.

  • You want low lift for digging as it permits handle to remain comfortably upright as you drive blade vertically into ground. High-lift handle throws you forward, off balance.

  • You want high lift for shovelling as it lets you slide the blade along the ground without bending over. A low-lift shovel makes you go into a tiring stoop to keep blade flat.


Hang” is the distance the blade is dropped below the handle line by the downward curve at the joint. You want a deep hang for horizontal shoveling and material moving. It lowers the load’s center of gravity and helps-like a pendulum-to keep the blade from tipping sideways and tiring your wrists.

You don’t want a deep hang, however, on a digging shovel; it would be harder to control. The off-center blade is more likely to wobble as you press it into the ground and to tip as you lever it out. It’s also more awkward to get a good down-thrust on the blade.

  • Look for blade “HANG” when choosing between digging and shoveling. For shoveling, a deep hang is low and stable. For digging, a shallow-hang blade is less likely to wobble.


Try the balance, too. Rest the shovel across a chair back like a seesaw. If it is correctly balanced, the blade will remain right side up. If it rolls over, upside down, it’s likely to do the same in use. The effort to hold the blade upright under a load will strain your hands and lead to blisters.

  • Try the balance by resting shovel across a chair back or other support. Blade should remain upright. If it flops over, it is unbalanced and will twist uncomfortably in your hands.


What length handle? The long handle is best for stand-up digging and scooping as it saves you stooping. It also gives you a longer reach for spreading topsoil and other materials.

The shorter D-handle is better where you want to toss loads with good accuracy. The crosspiece in the grip gives you something to push against at the start of the throw and something to haul back on when you “shoot” the load.

A D-handle is also a must for working in tight spots, as in a deep pit or trench. Only a little more than half the length of a long handle, it lets you grasp it easily at the end with one hand and just behind the blade with the other for good leverage and control.

  • Long, straight handle gives you more reach for stand-up shoveling without stooping or for getting down into pits and trenches. When hole is deep enough to stand in, switch to a short D-shaped handle. It lets you work in confined spaces, is easier to grip for tossing loads.

 

Mechanical Elephant

29 Aug

Cheap excitement for children, from October 1950.

  • This elephant lives on a gasoline diet. It can step along at 27 miles an hour with its load of thrilled youngsters.

Walking, waving its trunk and flapping its ears in a realistic fashion, a mechanical elephant may soon be popular at amusement centers because its “feed” bill is small. An attendant sits on the robot’s neck, operating the controls. The 8 ½-foot model is powered by an 8-horsepower engine and has a ½-inch thick “hide” of toughened paper. The exhaust pipe is hidden in the trunk. Made in England, the elephant contains 9000 parts and walks on a set of wheels concealed in the hollow feet. The elephant’s leg “bones” are filled with compressed air to add a natural “spring” to the ride.

  • Stripped of its tough skin, it looks like a plumber’s nightmare.

Destination Moon

28 Aug

The Greatest Adventure Awaiting Mankind!

It’s closer than you Think!

Be there! Be with the first men to ride a space-ship to the Moon! It’s a spine-tingling, perilous adventure!

See how the greatest news story of all time will actually happen! Share this adventure tomorrow!

Two years in the making, this is the picture you have heard about in LIFE, THIS WEEK, PARADE, the popular science magazines, New York Times and many more.

It’s a prophecy – not a fantasy! Watch for it at your favorite theatre!

Color by Technicolor

DESTINATION MOON

Produced by GEORGE PAL. Directed by IRVING PICHEL. Screenplay by RIP VAN RONKEL, ROBERT HEINLEIN and JAMES O’HANLON.

SEE the pull of gravity crush them deep into their crash-couches as the space-ship takes off at 32,000 feet a second.

SEE the flyers risk death as they crawl outside the space-ship to repair their short-wave arial – their only link with Earth.

SEE the slip that sends a crew member adrift in space – facing the doom of floating forever in the vast black universe.

SEE Man’s greatest thrill as he finally sets foot on the Moon! Now, at last, his age-old dream of conquering space comes true!

As advertised in September 1950

Gold, or perhaps not

27 Aug

Salting” of gold claims to improve them. I’ve heard of the “shotgun” method, but not some of these (from November 1940 Popular Mechanics):

Foiling the Gold Swindlers

  • False rivet in shovel handle allows gold dust to drop into gravel.

“Looks like gold,” agreed the stranger. “I’ll buy your claim if it runs high enough to pay but you’ll have to let me take a sample for assay.” “Sure thing,” the prospector assented. He shoveled together a pile of gravel, divided it into quarters, then discarded two of them. The balance he heaped up and quartered again, repeating the mixing and quartering until-finally the stranger took away a paper bag full of the remainder. When he called at his assayer’s for the report, he was summoned into the labaratory. “This stuff ran so high I could hardly believe it,” said the assayer. “Take a look.”

He dropped a tiny pinch of gold dust onto a glass slide and slipped it under a microscope. The other peered, saw the tiny grains magnified to the size of boulders. But unlike boulders, they were jagged. Across many of them ran deep scratches. “Did you ever see any square-cornered gold dust from a river bed?” demanded the assayer. “Placer gold rolls among the pebbles as it is carried downstream and soon gets rounded and smoothed. Notice those file marks. Somebody must have improved this sample with a little gold dust – from a watch case or a ring, probably.”

The miner grew indignant when accused of trying to salt his claim, but the prospective buyer suddenly grabbed the shovel used in quartering the sample. He examined it and learned the miner’s secret. When turned a certain direction, the hollow handle lined up two holes to release the hidden gold dust it contained – “sweetening” the sample to bonanza richness.

{Note: Placer gold is gold that has weathered from the host rock where it was formed and been “placed” either on hillside (eluvial placer), stream bed or alluvial fan by the action of water, glaciers or other geological forces.}

  • Needling gold solution into sample bag.

One thing a sucker needs to learn at once is to guard well his sample bags. With a hypodermic needle, a gold solution can be injected right through the sealed bags; or the solution can be dropped on them and allowed to soak through. Shrewd individuals use a sealed paper sack as an inner lining for the regular cloth bag. A needle hole or a stain reveals any tampering.

  • Gold dust being rolled in cigarette.

Carelessly flicking the ash from his cigarette as he picked off chunks of ore, an old-time salter could easily load the samples with gold dust. An ordinary, roll-your-own cigarette can be loaded with 200 milligrams or so of gold, enough to make the assay show sensational values. But again the microscope betrays the true character of the grains. If polished from rolling in a stream bed, they would be out of place in a hard-rock mine where the ore must be picked or blasted from solid quartz.

  • Hole down center of this drilling bit lets gold dust fall out.

  • Spraying gold solution onto rock to salt sample.

One salter, noticing a balcony overhanging the open workshop where an assayer’s furnace was located, climbed upstairs and fed grains of gold into the samples by poking them through a knothole in the floor. Another assayer became suspicious of the reports his methods were getting but his client insisted the samples couldn’t have been touched before they reached the laboratory. The assayer discovered somebody had “spiked” the gasoline for the assay furnace with a gold solution.

Hotels with Staff

26 Aug

Back in the 1940s, hotels had far larger staff than the modern day. This description comes from October 1940 Popular Mechanics:

HOME WAS NEVER LIKE THIS

Imagine being host to from 2,000 to 4,000 guests a day. There are always that many registered at any one of New York’s largest hotels,  with two to three thousand employees to serve them. At least 5,000 visitors drop in daily for a meal or chat. That crowd would equal the  population of a good sized little city. The biggest hotels serve 12,000 meals a day. It takes a lot of food to be ready for such a crowd, and hundreds of tons of ice daily just to keep it in a fresh condition.

  • This isn’t the entire bakery, it’s merely the shop where bread and rolls for hotel patrons are baked.

One of the world’s largest hotels, located in New York, has four general kitchens to prepare food for its seven dining rooms, each of which has its own menu. Another kitchen specializes in preparing soup in fifty-gallon cauldrons. A bakeshop with ovens eighteen feet deep turns out 20,000 rolls, 700 loaves of bread, every day. But no pies or cakes or pastries – these are made in still another bakery. There is even an ice-cream chef with his special kitchen, turning out 400 gallons of frozen desserts.

They freeze their own ice. Some of it, chopped by a machine which macerates an entire 300-pound cake at a time, is served on the table with oysters, grapefruit or wines. Air is circulated through other cakes to keep them crystal clear; then a machine containing rows of revolving saws cuts the cakes into cubes for your glass of water or iced beverage.

This same hotel’s laundry washes and irons sixty to seventy thousand pieces each day. A guest can arrive at midnight, have his clothes washed, his suit pressed, and arise at eight o’clock to find everything clean, stowed neatly in his bedroom door. The secret of speed is in drying. Water is forced from the washed clothes by centrifugal extractors, until they are just right for ironing. A battery of ironers turns out shirts two a minute. The first machine presses the collar, the next does the front, a third irons the back, while the sleeves are pressed and creased on heated metal arms. The last machine turns down the collar, irons the shoulders and cuffs, after which any missing buttons are sewed on by another machine. A woman then touches up each shirt with a hand iron. After that they are folded on a gadget that does everything but think; then a pasteboard cover is slipped on.

One woman irons all socks by slipping them over a heated metal foot. There are four feet in a line, by the time she places a sock on the fourth, the first one is ready to come off. Socks having holes are darned on a machine in the time it would take you to thread a needle.

  • Power plant for lights, machinery and elevators.

The hotel’s electric plant in the subbasement supplies current to run the elevators, light 25,000 electric bulbs, recondition the air. The hotel itself contains 1,020 miles of electric wire, and this doesn’t include wiring for the 3,340 telephones. Two huge compressors furnish air for the pneumatic tubes, the laundry presses, and to agitate the ice. A central vacuum cleaner in the subbasement has 324 outlets. There are 112 miles of plumbing pipes, carrying hot, cold, and ice water to the 2,200 rooms. In summer 15,000 gallons of ice water are cooled each day, while 45,000 gallons of hot water are used – half a barrel a second.

  • There’s nothing on your floor to blaze except the bedding and what you bring with you, but the hotel’s own fire department is ready for anything.

The hotel has its own fire department, with as large a personnel as you will find in a city of 100,000. Every male employe is a member, has his own station, his special duties to perform should the alarm be sounded. There is a fire truck in the basement, with hose, chemical extinguishers and smoke masks, yet small enough to ride the elevators.

  • A hotel telephone switchboard big enough for a small city – which a metropolitan hotel really is.

The telephone switchboard is the largest private exchange in the world, its thirty five operators handling 250,000 calls a month. For three hours each morning seven operators do nothing but awaken guests. Supplementing the telephones are several miles of pneumatic tubes, three telautograph systems, and a private teletype, all for the speedy transmission of messages.

  • Floor clerk’s message transmitter.

  • Battery of pneumatic tubes in hotel’s message center.

Does the faucet in your room drip? You tell the operator, who writes a message on the telautograph. A woman in the message center tears off this note, places it in a tube cartridge, where it is shot by compressed air direct to the plumber in the subbasement. Does somebody call you when you’re out and leave a message? The operator writes it on the telautograph, and the pneumatic tube shoots it to your floor clerk, who hands it to you when you ask for your key upon returning.

  • Information clerks tell you if the John Smiths of Dubuque are registered.

A big hotel is really a complete city under one roof. One could come to New York over any of several railroads, step directly from the station into the lobby of half a dozen of the biggest hotels. Using the sub way system and underground walks, he could shop in the department stores, do business in many office buildings, attend the theater without ever stepping out of doors. He could even undergo a major operation in the hotel’s own hospital.

  • New arrivals are shown to suite by bell boy.

  • Glasses are washed, hand dried and polished, sterilized and wrapped in Cellophane.

Falling correctly

25 Aug

A useful summary from Eugene A Hanson in August 1950 Popular Mechanics:

  • Men have dropped into the sea from astounding heights this way – and lived to tell about it. By keeping toes pointed, body straight during the fall, jumper cuts the water’s surface with almost no resistance.

Land Alive

TWO MEN are trapped by smoke and flames on the fourth floor of a burning building. Leaping from the window is their only possible escape.
One man, even though death is certain in the fire, is afraid to jump. His friend slugs him on the jaw and throws him out of the window and he lands flat on his back. The braver man then leaps out and lands on his feet.

Which of the two men will survive?

It will be the coward who lives, though badly injured, while the man who landed on his feet will be speared through his vital organs by his own thigh bones. Countless cases of men falling from great heights were analyzed by the Navy and it was found that by far the best chance of survival occurred when the victim landed flat on his back. Falling from a lesser height, on the other hand, the least injury will be suffered when the victim, for instance a man falling from the roof of a two-story building, takes the initial shock on his feet but distributes the force of his fall by letting his body roll.

The Navy considered the problem of how to fall safely so important that a special training film was made during the war to teach such know-how. The man who demonstrated the various techniques for falling safely was a former professional tumbler, Bruce Connor, who is now a physiotherapist in Los Angeles and spends a good part of his time teaching paralyzed war veterans how to walk on crutches, and in case of accident how to fall off the crutches without being hurt.

Connor says many lives would be saved and countless injuries avoided if every school child were taught, as part of the physical-education curriculum, how to take a fall properly. He sums up the findings with two bits of advice:

First, always try to roll your body in the direction you are falling; second, always try to land as flat as possible.

This applies to ordinary falls, those which can happen to anyone at any time, just as much as to the more spectacular accidents, Connor makes it clear. He who slips on ice, a rug on a smooth floor or a roller skate usually falls backward, and the point most susceptible to serious injury is the end of the spine. If you remember to try to land flat, you will arch your back and thus keep from landing on the vulnerable tailbone.

In falling forward, on the other hand, the exact technique depends on how fast you are moving. If you trip at ordinary walking speed, you can ordinarily save yourself by, catching your weight on your hands in the push-up position. If you are carrying something, drop it. Don’t try to catch your weight on one arm. You’re likely to break it.

If you fall when running, try to go into a football roll. Twist sideways and land with a rolling motion, hip, side and shoulder taking the first shock, and with knees bent, arms close to the body. If you do this properly, you’ll roll right to your feet again in one smooth motion.

Falling at high speed, as from a running horse, an automobile or train, your best bet is the log roll. Keep the body straight for this, with legs stiff, chin against the chest, elbows over the stomach and hands over the face. The roll must be a perfectly sideways spin, with no end-over-end action that would thump the head against the ground. Pulling in the elbows will help to make the roll less bumpy.

When falling headlong, as when tripping on a stairway or off some elevation, the forward roll is called for. The hands touch first in this roll, and take some of the shock. The chin is tucked against the chest and the shoulders take the main shock as the body rolls forward.

Like all other rules, those on how to fall have their exceptions. If you should slip and fall on a steep mountain slope, you might do well to spread out arms and legs to prevent rolling with the fall, because in this case the rolling might be hard to stop – the exception to the rule about rolling in the direction of the fall. The other rule – try to land as flat as possible – has its exception when the victim is falling from a great height into deep water. In this case, try to land feet first, with toes pointed, elbows hugging the stomach and hands over the face.

As for his advice against the wrong way to fall – don’t ever put out one arm or one leg to break a fall – he couldn’t think of a single exception.

  • In tumbling from a fast moving auto or train, the log roll is the best method of avoiding serious injury. Arms are held close to the body, with the hands sheilding the face during the roll.

  • When you trip, moving at slow speed, extending arms is easiest way to break the fall before landing flat.

  • When you slip, this is the safest way to land. The feet, arms and shoulders rather than the vulnerable base of the spine, will absorb most of the shock.

  • Somersaulting forward is the best way to break a headlong fall.

  • A running fall should be taken by going into a football roll. Hip and shoulder take the impact, and you can roll right back to your feet.