H-Bomb Concussion Could Level City

Press, Volume XCIII, Issue 27962, 8 May 1956, Page 13

H-Bomb Concussion Could Level City

(N.Z. Press Association—Copyright) (Rec. 10 p.m.) NEW YORK, May 6. A nuclear bomb exploded at ground level could shake a city to pieces with its earthquake-like concussion, reporters aboard the U.S.S. Mount McKinley at Bikini atoll were told today. This was one of the new details of the tremendous power of the hydrogen bomb made known after bad weather forced the postponement of a big hydrogen blast scheduled for Tuesday. The big hydrogen bomb air-drop trial was reset tentatively for Wednesday, but Dr. William Ogle, acting scientific test director of the United States joint task force, told reporters he would not be surprised if the weather forced a postponement to as late as May 15.

Until now. little has been said about the earthquake-like effect of the nuclear bomb, which also destroys and kills by blast, heat flash, instantaneous radiation, and the slow poison of radioactive contamination.

But reporters, invited to the midPacific proving ground to watch the scheduled test shot of a hydrogen weapon dropped from the air, and to inspect the area, learned some of the things the scientists have discovered about this little-discussed matter. The detonation of a hydrogen bomb at ground level produces a special effect which virtually makes it a new weapon—a sort of “Q-bomb” for creating an earthquake. The visiting reporters and civil defence observers saw some examples of what a surface detonation can do. They looked down from a plane into the mighty crater ripped out by an Hbomb detonated by the United States two years ago. Blue water filled a two-mile-wide cavity where an island of the Bikini atoll once stood. Crushed coral and sand were piled in mounds along the lagoon side of the crater, thrown out by the mighty blast. Shocks 20 Miles Away

Some indications of the far-reaching effect of this earth-shaking blast came from Atomic Energy Commission scientists. Dr. Gaelen Felt, who heads the scientific test group, said in answer to a question that he had observed definite earth shocks while in a concrete bunker on Enyu Island during the surface explosion of the thermonuclear weapon.

Surface detonations are conducted on the northern perimeter of the atoll —2O miles from the bunker on Enyu Island.

Dr. Ogle said that instruments showed that another unmanned concrete bunker on an island seven miles from the site was rocked.

Civil defence experts estimate that even a two-inch movement of a brick building in an earthquake can bring it tumbling down. An American Associated Press reporter on the Mount McKinley said in his dispatch that from the visible evidence and the cautious answers of the nuclear weapons experts, it seems possible that the radius of total or heavy destruction by artificial earthquake might be up to eight or 10 miles.

Added to this would be the result of the lateral blast of the bomb, its deadly radiation, and the heat from

the flash. But the scope of these three effects would be less than that produced in an air burst. The ground-level test shots at Bikini also produce a tidal wave, even as far away as Enyu Island. The water of the lagoon sometimes surges up to a four or five-foot level around the control centre bunker. Bulldozers have been used to build a levee of sand around the bunker’s base. Recording the Blast Reporters today saw an instrument capable of reporting an atomic reaction lasting only one-thousandth of one-millionth of a second. The instrument and others, equally ingenious in recording bomb effects, were displayed for the first time to reporters during a tour of Bikini and Eniwetok atolls. The two atolls bristle with devices for measuring the nature and effects of nuclear weapons. The fastest acting instrument was one used to detect gamma radiation. Other devices monitor long-lasting residual radiation. Dotted among the isles are heavily shielded batteries of cameras prefocused to record the bomb’s flash and fireball. They are ultra fast, using rotating mirrors capable of resolving time into fractions of a millionth of a second. The control bunker on Enyu Island at Bikini can simultaneously fire a distant weapon and set cameras and other instruments working. In the case of the hydrogen-bomb airdrop, the delivery plane will switch on the instruments with a radio signal as the bomb begins to fall. At the same time, a magnetic tape with a voice “count down” will begin unwinding and broadcasting from the bunker. If the timing is perfect, the bomb will go off when the voice says “zero.”

Duke at Polo.— Th Queen. Prince Charles and Princess Anne in Windsor Great Park, saw the Duke of Edinburgh score his side’s two goals today when the polo season opened The Duke’s team, the Welsh Guards, lost to the Royal Horse Guards by a half goal.—London, May 7.