COMPACT ATOM BOMBS

Press, Volume XC, Issue 27306, 24 March 1954, Page 11

COMPACT ATOM BOMBS

Smuggling Into U.S. Feared (N.Z. Press Association—Copyright) (Rec. 11.30 p.m.) NEW-YORK, March 23. The “New York Times,” jvhich earlier this year forecast that law enforcement officials would be warned that it was now possible to smuggle compact atom bombs into the United States, today published in a report from Washington a description of two such devices, circulated by the Federal Bureau of Investigation last January. The report said that the descriptionbad been authorised by President Eisenhower and an accompanying letter, sent by the director, of the F. 8.1.. Mr J. Edgar Hoover, had been obtained from an authoritative source.

The description said it was impossible to, say what a foreign atom bomb would look like, but it was possible to explain the basic ideas that would govern the design.

Atomic explosions resulted when, first, certain amounts of fissionable materials in two pieces or more are brought quickly together to form one piece of such material, and, second, when a certain amount of fissionable material is quickly made denser by squeezing it together.

“In the first case what to look for is some kind of gun barrel device using a high explosive to blow one piece of fissionable material from the breach end of the gun down through the barrel into another piece of fissionable material firmly anchored in the muzzle of the gun. “In the second case what to look for is a device using a high explosive to squeeze fissionable material,” said the newspaper. The description said that 50 pounds of uranium or plutonium is' no larger than a sphere two and a half inches in diameter. Such a sphere can be surrounded by charges of conventional high explosives to create “implosion”—a bursting' inward, to compress, and thus set off, fissionable material. “Should Be Alert”

“Since uranium and plutonium can be coated with other metals or plastic that will defy geiger counters and can be machined into all sorts -of shapes we should be especially alert regarding any article that is extremely heavy for its size,” the description said.

Regarding the gun-barrel type, the description said that the bore of the barrel “would probably not be less than two inches or more than 10 inches” arid the outer diameter would range from about five inches to 12. But the tube and two of the breech blocks could be smuggled in as three separate pieces and the* fissionable material might be carried in separate packages. ‘ . Mr Hoover’s letter said special 'assignment units had been designated to disarm any atomic weapon that might be discovered. Law enforcement officers were requested not to attempt to dismantle any apparent atomic device.