"Eye of newt, and toe of frog,
Wool of bat, and tongue of dog,"
"Adder’s fork, and blind-worm’s sting,
Lizard’s leg, and owlet’s wing"
"Scale of dragon; tooth of wolf;
Witches’ mummy; maw and gulf
Of the ravin’d salt-sea shark;"
"Root of hemlock digg’d i the dark;
Liver of blaspheming Jew;"
"Gall of goat, and slips of yew
Sliver’d in the moon’s eclipse;"
"Nose of Turk, and Tartar’s lips;
Finger of birth-strangled babe
Ditch-deliver’d by a drab,—"
"from Macbeth (1606) by William Shakespeare"
Curve - - The Thing!!
"that you can, so to speak, design them freehand.'" - - Freeman Dyson.
THEM being an atomic bomb, a device exploding as is understood for a nuclear weapon to explode, radiation, flash, blast.
And as described in the book: "Curve of Binding Energy". Ted Taylor in a mere fraction of the time as might have been expected, designing in a "freehand" manner, using his accumulated knowledge and expertise, a device, an atomic bomb that had the capability to explode with kilo-ton force. The type of atomic device that might be assembled by someone working in the basement or garage of their home!
[as usual, let me remind each and every devoted reader to the blog that this book "Curve" was originally written in 1973/1974!!]
That requisite amount of fissionable weapons grade U-235 [95 % pure] fabricated into a device - - a gun-type uranium bomb similar to the ordnance dropped on Hiroshima. The design of Ted Taylor a GADGET without sophistication, crude and rudimentary but do-able and work-able.
"It was a thing about three and a half feet long, and it has seven principal components: projectile, target, initiator, reflector, propellant, container, firing system . . . It weighed five hundred pounds."
1. The target:
"The basic requirement was that two sub critical pieces of metallic uranium come together very quickly. In the presence of a surrounding reflector, which could be made of steel or any other material that would tend to reflect neutrons back into the core, the assembled uranium would be super critical. The nearly instant result of a fission chain reaction begun after the assembly became super critical would be a nuclear explosion."
That quantity of fissionable weapons-grade uranium needed being:
"the critical mass U-235 inside three inches of steel was twenty-six kilograms; one inch of steel, thirty kilograms; a half inch of steel, forty kilograms . . . Taylor decided on a forty-kilogram cylinder of uranium, which would be five and half inches in diameter and five and half inches long. The cylinder consisted of two parts - - a sort of plug two and three -quarters inches in diameter and five and a half inches long . . . fired down a gun barrel and into the larger piece, the target."
"critical mass - - noun 1. Physics . the amount of a given fissionable material necessary to sustain a chain reaction at a constant rate.
Those two pieces of uranium molded and shaped in:
"magnesium-oxide crucibles, he [Taylor] said - - which, in turn, had been shaped by hand."
"cru·ci·ble - - noun 1. a container of metal or refractory material employed for heating substances to high temperatures."
2. The projectile:
"the projectile would have a piece of steel screwed to it, riding piggy back behind it, [and with] "a lithium wafer [glued] to the front of the projectile"
3. The reflector:
"the reflector could be made from . . . cast iron block with a hole drilled in it - - or from . . . solder, which is tin and lead might be a shrewder choice. [spools and spools of solder]
4. Firing system and propellant:
"Buy an old cut-up three-inch naval gun barrel from a military salvage yard . . . Plain gunpowder . . . the projectile's weight was more or less thirty-five pounds. Less than two ounces of gunpowder could make it move five hundred feet per second down the gun barrel. Put the gunpowder into a small plastic bag. Run a wire from a flashlight battery to the bag. Connect the battery to an alarm clock. In place of the clock you could use a preset mechanical fuse."
5. The initiator:
"the designer would incorporate an initiator - - an instant source of neutrons. There many ways to make initiators, all involving two or more materials that, brought together, will emit neutrons . . . One way to do this would be be to buy some lithium from a chemical-supply house, shave off a little with a knife, and glue a lithium wafer to the front of the projectile. A tenth of a curie of polonium-210 . . . could be glued to the steel at the far end of the target. When the lithium hits the polonium a burst of neutrons will scatter in all direction into the uranium."
6. The container:
"For the bomb Taylor conceived . . . a garbage can would do . . . Its overall size was three feet six inches by eleven inches."
Such bomb would have a yield of: "He [Taylor] said a kiloton."
That only difficulty being to obtain that amount of absolutely WEAPONS GRADE [95 % PURE] U-235? A quantity of about 110 pounds [50 kilograms], that quantity in a mass about the size of an American football!
Fabrication of such a device can be seen as NOT being beyond the capabilities of a terrorist group OR that talented and adept and resourceful lone amateur, a technologist or technician, a person variously referred to as the "mad man" or "highly disaffected" individual. OR someone perhaps, just doing IT for the thrill?
Scary, isn't it?
coolbert.
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