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Topic: Who "developed" the atomic bomb?
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Tom Potter

Posts: 497
Registered: 8/9/06
Who "developed" the atomic bomb?
Posted: Feb 21, 2013 12:26 AM
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As people motivated by race and religion,
have distorted the history of nuclear physics
and the creation of the atomic bomb,
in the interest of truth and honesty,

I have listed a ***1937*** magazine article that
features the ACTUAL leaders in the nuclear physics field
at that time.

Observe that General Groves ran the Manhattan Project
on his own, and Lawrence was his physics advisor
and had access to all of the information
and all of the Manhattan Project sites,

and that although a STUDY group
to research the possibility of creating a nuclear bomb
had been created that the program was not taken seriously
until Lawrence briefed FDR.

===========================

Science: Cyclotron Man Monday, Nov. 01, 1937

Four years ago a promising young physicist from the University of
California, **Ernest Orlando Lawrence**, left his sunny campus and the
ramshackle old building in which he was working, traveled eastward
across the U. S. and across the Atlantic to attend a European
scientific conference in Brussels.

He was the **only** U. S. scientist
invited. He had invented and was already making formidable use of
a curious and powerful atomic weapon-a "cyclotron" that imparted
great speeds to projectiles for smashing atoms by whirling them
around in a strong magnetic field.

In Brussels was Britain's gruff, burly Lord **Ernest Rutherford**,
great formulator of the atom's electrical structure, revered
director of Cambridge University's Cavendish Laboratory. Also on
hand was one of Rutherford's imaginative young workers, **John
Douglas Cockroft**, who was at that time splitting lithium atoms by
hurling protons at them. Cockroft energized his protons with high
voltages obtained by transformers, rectifiers and condensers.

Cockroft realized the greater potentialities of the Lawrence
machine, had tried to persuade Lord Rutherford to acquire one.
Rutherford was unimpressed. In Brussels, Cockroft asked Lawrence
to give the old physicist a sales talk. Lawrence assented. Lord
Rutherford declared it to be one of his principles that the
equipment used at Cavendish should be developed there. Young Dr.
Lawrence made a quick-witted thrust: "Sir, you use spectrometers
in the laboratory every day, but they weren't invented there, were
they?"

Two years ago Cambridge announced that it would build an atom-
smasher of the Lawrence type. The Cavendish workers now expect
their machine to be running in about a month. But Lord Rutherford
will never see it start. He died last week, aged 66, after failing
to rally from an abdominal operation. His passing evoked
expressions of grief and tribute from all over the scientific
world. Said 80- year-old Sir J. J. Thomson, famed discoverer of
the electron, who once was Rutherford's teacher: ''His work was so
great that it cannot be compassed in a few words. His death is one
of the greatest losses ever to occur to British science."

Ernest Rutherford was one of the old pioneers in atomic physics
and Ernest Orlando Lawrence is one of the new. Last week Lawrence
was again traveling eastward, bound for Rochester, N. Y. where the
National Academy of Sciences meets this week. Not only as the
originator of the cyclotron but as the foremost U. S. destroyer
and creator of atoms, the No. 1 U. S. investigator of artificial
radioactivity and the headmaster of what is in effect a school for
atomic physicists, he was to receive the Comstock Prize ($2,500
and a certificate). With a membership limited to 300, the National
Academy is the lordliest body of scholars in the country and the
Comstock Prize, its highest honor, is awarded only once every five
years. In many quarters it is regarded as the highest U. S.
scientific honor.

Atom Anatomy. The largest atom is only .00000001 inch in diameter,
and many of the most important atoms handled by physicists are
considerably smaller. An ancient Greek, Democritus, coined the
word "atom" which means indivisible. For thousands of years this
was a perfectly good name but for the past two decades, since the
first atoms were sundered, it has been archaic.

An atom, consists of bundles of negative and positive electricity
(electrons and protons) and particles without electric charge
called neutrons.* Practically all the mass of an atom is
concentrated in the nucleus, which is positively charged. In a
stable atom the positive charge on the nucleus balances the
negative electronic field outside. The lightest atom, hydrogen,
has one nuclear proton and one electron spinning around it. The
heaviest, uranium, has 92 protons and 146 neutrons in the nucleus,
with a cohort of 92 electrons outside.

Splitting the atom means splitting the nucleus. Physicists want to
do that for the same reason that every anatomist since Vesalius
has wanted to cut up human bodies-to find out what is inside and
how it works, about which they still have plenty to learn.

To smash atoms requires: 1) a projectile of the same size range as
the atom; 2) a means of imparting high speed to the projectile; 3)
a target containing the atoms to be smashed (a platinum screen, a
tungsten wire, a pinch of phosphorus) which can be placed in the
path of the bullets; 4) a means of identifying the wreckage, so
that the investigator may find out what has happened. A common
atomic projectile is the nucleus of hydrogen, the proton. Protons
are prepared by stripping the electrons from ordinary hydrogen gas
by means of an ionizing electrical current.

These ionized particles are allowed to flow into an atom-smashing
machine, of one kind or another, in which electrical impulses pick
them up and hurl them at a target. A few protons score hits,
splitting a nucleus into two or more fragments. The projectile
itself may combine with a fragment or fragments to form a new
substance. Or it may lodge in the nucleus, creating an overweight,
unstable body which begins to give off particles and gamma rays.
This is called artificial radioactivity.

Best device for studying the debris is the "cloud chamber" which
won a Nobel Prize for its inventor, **C. T. R. Wilson** of England. If
this is placed next to the target, some fragments of the
disintegrated atoms fly into it. The chamber contains water vapor
which condenses on the trail of the fragments as droplets of fog
which can be photographed. From the thickness of the fog path and
its curvature in a magnetic field, much can be told about the mass
and speed of the fragments and their electric charges.

In the pioneer days of atom-smashing, projectiles energized by
Nature were used: the particles which spontaneously fly out of
radioactive substances (radium, polonium, thorium, et al.) at
enormous speed. This was the method which Lord Rutherford used for
the first demonstrable nuclear disintegrations in 1919.
Physicists, however, are as firmly convinced as militarists of the
virtues of mechanization. Dr. Lawrence calculates that his
cyclotron, operating at 5,500,000 volts, produces as many
particles as would emanate from two pounds of radium-which is more
radium than exists in the world.

Machines. Atom-smashing machines, most spectacular exhibits of
laboratory science, have one feature in common: they must be huge
in order to build up and handle the tremendous particle energies
which they require for their work. In general they are of three
kinds. The first, developed both in England and the U. S.., builds
up high voltages by means of transformers and condensers. The
second stores static electricity on balloon-sized electrodes until
the potential is such that a mighty flow of direct current crosses
the gap. For technical reasons, notably the difficulty of
constructing a discharge tube which will handle the flow of high-
voltage particles, the practical upper limit for these types is
about 2,000,000 electron-volts. Massachusetts Institute of
Technology, which had a giant electrostatic generator shooting
7,000,000-volt sparks from electrode to electrode four years ago,
has not yet put it to work smashing atoms because of the discharge
tube problem.

The cyclotron of Ernest Orlando Lawrence neatly finesses such
troubles by making a comparatively small voltage act on a particle
repeatedly until it attains a speed corresponding to extremely
high voltage, thus dispensing with a discharge tube altogether.
Most conspicuous feature of the apparatus is an 85-ton electro-
magnet whose poles face each other vertically across an 8-in. gap.
In the gap is placed a shallow cylindrical tank, pumped out to a
high vacuum so that particles inside may move freely without
interference from air molecules. Ions such as deuterons (nuclei of
heavy hydrogen) are fed in at the centre.

By means of a radio-frequency oscillator a rapidly alternating
potential of 50,000 volts is maintained across the tank. Under
this influence the deuterons in the centre start to move outward.
The effect of the big magnet is to pull them in circles. Just as
they complete a half-circle the voltage is reversed, so that they
get a kick of 50,000 volts to boost them around the other side of
the circle at higher speed. After another half-circle the reversed
voltage hits them again, and so on. The deuterons go spiraling
outward, faster and faster, toward the rim of the tank. After
being kicked 100 times by 50,000 volts, they attain speeds of
5,000,000 electron-volts. As they approach the rim of the tank,
they are guided by a deflecting plate through a window and thence
against any target the researchers choose.

The newest set-up at Berkeley, which has been operating for two
months and which Dr. Lawrence described this week in Rochester,
has a vacuum tank 37 in. across, hurls deuterons at 7,800,000
volts. If these are directed into a beryllium target, the
beryllium belches out at least one trillion neutrons per second,
possibly ten trillion.

The "Breaks." Lawrence conceived the basic idea of the cyclotron
in 1929 when he read a paper by an obscure German on the behavior
of ions in a magnetic field. Next year he and three co-workers -
**Niels Edlefsen, M. Stanley Livingston and David Sloan** -built the
first cyclotron with a tank six inches across and a small magnet.
It worked, but Lawrence pined for a bigger magnet.

Machines. Atom-smashing machines, most spectacular exhibits of
laboratory science, have one feature in common: they must be huge
in order to build up and handle the tremendous particle energies
which they require for their work. In general they are of three
kinds. The first, developed both in England and the U. S.., builds
up high voltages by means of transformers and condensers. The
second stores static electricity on balloon-sized electrodes until
the potential is such that a mighty flow of direct current crosses
the gap. For technical reasons, notably the difficulty of
constructing a discharge tube which will handle the flow of high-
voltage particles, the practical upper limit for these types is
about 2,000,000 electron-volts. Massachusetts Institute of
Technology, which had a giant electrostatic generator shooting
7,000,000-volt sparks from electrode to electrode four years ago,
has not yet put it to work smashing atoms because of the discharge
tube problem.

The cyclotron of Ernest Orlando Lawrence neatly finesses such
troubles by making a comparatively small voltage act on a particle
repeatedly until it attains a speed corresponding to extremely
high voltage, thus dispensing with a discharge tube altogether.
Most conspicuous feature of the apparatus is an 85-ton electro-
magnet whose poles face each other vertically across an 8-in. gap.
In the gap is placed a shallow cylindrical tank, pumped out to a
high vacuum so that particles inside may move freely without
interference from air molecules. Ions such as deuterons (nuclei of
heavy hydrogen) are fed in at the centre.

By means of a radio-frequency oscillator a rapidly alternating
potential of 50,000 volts is maintained across the tank. Under
this influence the deuterons in the centre start to move outward.
The effect of the big magnet is to pull them in circles. Just as
they complete a half-circle the voltage is reversed, so that they
get a kick of 50,000 volts to boost them around the other side of
the circle at higher speed. After another half-circle the reversed
voltage hits them again, and so on. The deuterons go spiraling
outward, faster and faster, toward the rim of the tank. After
being kicked 100 times by 50,000 volts, they attain speeds of
5,000,000 electron-volts. As they approach the rim of the tank,
they are guided by a deflecting plate through a window and thence
against any target the researchers choose.

The newest set-up at Berkeley, which has been operating for two
months and which Dr. Lawrence described this week in Rochester,
has a vacuum tank 37 in. across, hurls deuterons at 7,800,000
volts. If these are directed into a beryllium target, the
beryllium belches out at least one trillion neutrons per second,
possibly ten trillion.

The "Breaks." Lawrence conceived the basic idea of the cyclotron
in 1929 when he read a paper by an obscure German on the behavior
of ions in a magnetic field. Next year he and three co-workers -
Niels Edlefsen, M. Stanley Livingston and David Sloan-built the
first cyclotron with a tank six inches across and a small magnet.
It worked, but Lawrence pined for a bigger magnet.When **Dr. Leonard
Fuller**, head of electrical engineering at the university, heard of
this he asked Lawrence how an 85-ton magnet would suit him.
Lawrence gasped. Dr. Fuller also happened to be vice-president of
Federal Telegraph Co., which had built four 85- ton magnets for
round-the-world radio transmission during the War. Peace came
before this particular magnet could be shipped to China and ever
since it had lain idle at Palo Alto. Dr. Fuller and Dr. Lawrence
jumped into an automobile and roared down to Palo Alto. Soon the
big magnet was installed at Berkeley.

Lawrence regards this gift as one of his two luckiest '"breaks."
The other was the fact that University of California's **Gilbert
Lewis** was making heavy water, containing heavy hydrogen, soon
after its discovery by Columbia's Urey. Lewis let Lawrence have
generous samples and Lawrence was the first man to use the heavy
hydrogen nuclei-deuterons-as atomic projectiles. They are more
effective than protons, easier to handle than alpha particles.

Mass Attack. The volume of results piled up at Berkeley is
impressive. Much of it consists of data on hundreds of radioactive
elements created by bombarding almost all the 92 standard
elements-what projectile was used, what energy, how quickly the
artificial radiation subsides, what it consisted of. In altering
atomic structures, Dr. Lawrence has even created a few atoms of
gold, thus technically at least realizing the old dream of the
alchemists. But the raw material for this transmutation was
platinum, and the few gold atoms were not worth a fraction of the
energy used in manufacturing them, although the electric current
necessary to run the cyclotron for an hour costs only $1.50.
"Anyway," as Lawrence remarks with a grin, "the information we are
getting is worth more than gold."

The Berkeley researchers have also created a small trace of Radium
E-not a temporarily radioactive substance but actual radium. The
Lawrence cyclotron technique has in the past five years come to be
recognized as the most efficient atom-smashing device in the
world. Eleven cyclotrons are either in operation or being built in
the U. S., one in Canada, eleven in Europe and the Orient. And
many of these projects are directed or staffed by men who learned
their cyclotron technique as research fellows under Ernest
Lawrence at Berkeley.

Radiations & Flesh. To guard against injury from radiations in the
vicinity of the cyclotron, Dr. Lawrence's crew carry small
electroscopes in their pockets which they discharge into a meter
at the end of the working day to see how much radiation they have
been exposed to. Since neutrons cannot be controlled by magnetic
fields and slide easily through almost all substances except those
rich in hydrogen, Dr. Lawrence moved the control panel 60 ft. away
from the apparatus and surrounded the machine with tanks of water
six feet high, three feet thick (every water molecule contains two
neutron-braking hydrogen atoms). No one is allowed inside this
barrier when the cyclotron is running. Experiments on rats exposed
to heavy neutron bombardment revealed a destructive effect on
their white blood cells, and if exposed long the rats died.

But neutron rays, and also the emanations from artificially
radioactive substances, may turn out to be beneficial instead of
harmful if artfully managed. Lately the biological and medicinal
possibilities of cyclotron products have loomed increasingly large
on the scientific horizon. In a malodorous room near the cyclotron
chamber at Berkeley are stacks of cages containing white rats,
labeled by splotches of blue, yellow or pink paint on their backs.
These animals have been made cancerous by implantations of
cancerous tissue. Preliminary experiments tend to show that
neutron bombardments have a selective effect on cancer cells five
times as strong as that of X-rays.

When Lawrence made sodium radioactive, the prospect arose of
administering salt containing radio-sodium, as a saline solution
to be swallowed or injected. The radiation dwindles by half every
15 hours and practically dies out in a few days. This was tried on
some patients at the University of California hospital, and
although the results were inconclusive, Lawrence feels that no
such promising line of investigation should be dropped until it
has been followed out further. His brother, **Dr. John Lawrence** of
Yale Medical School, is helping him with the biological research
and writing reports for medical publications. Another possibility
is to trace the metabolism of iron and calcium in the body by
means of radio-iron and radio-calcium.

During the past month workmen have been laying the concrete floor
of a big new laboratory next to the old building. In this a
tremendous cyclotron with a 220- ton magnet will be installed,
hurling deuterons at 12,000,000 to 20,000,000 volts, alpha
particles at 24,000,000 to 40,000,000. When completed the new
building will contain biochemical laboratories and a clinic. San
Francisco's late William Henry Crocker gave $75,000 for this
project, the Chemical Foundation $68,000, Dr. Lawrence estimates
that he needs about $35,000 more. Designer of the new equipment is
quiet, able **Dr. Donald Cooksey**, assistant director of the
laboratory for the past three years.

Jovial Captain. Ernest Orlando Lawrence has an ideal temperament
for a man who, in such a position, must be an educator and
organizer as well as a crack physicist. He is jovial and easy-
going but knows how to handle men and get things done. His
grandfather was an immigrant from Norway, his father a
schoolteacher. Born in South Dakota 36 years ago, young Ernest was
a boyhood friend of Merle Anthony Tuve, now a brilliant physicist
of the Carnegie Institution of Washington. One summer he clerked
at night in a hotel, another summer he sold aluminum ware in the
farming region, obtained a brand-new Ford by a series of
progressive trades starting with a very old Ford. He went to the
University of South Dakota, did graduate work at Minnesota and
University of Chicago, became an assistant professor at Yale, went
to California in 1928. He is married, has two children. He plays a
bang-up game of tennis, not hesitating to take on a onetime
Harvard tennis captain. He enjoys good food and drink and his
favorite San Francisco restaurant is Pierre's. Last commencement
he received kudos from three institutions-Stevens Institute of
Technology, Princeton, Yale."

Success has many fathers,
but failure is fatherless.

--
Tom Potter

http://the-cloud-machine.tk
http://tiny.im/390k






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