BOMBS AT BIKINI 



small ice crystals. Sucli an ice-cap, never before pro- 

 duced by man, can only form when the meteorological 

 conditions are exactly right. 



The mushroom did no damage, but it was far more 

 fearsome than its soft white form could suggest. In it 

 were shrouded the bomb 's deadly fission products ; for 

 in such a ''self -cleansing" explosion as this, nearly all 

 the bomb products remain in the air and are carried 

 aloft in the mushroom. The amount of radioactive 

 fission products infesting the cloud was small in terms 

 of weight. But its potency was impressive, being tem- 

 porarily equivalent to hundreds of tons of radium. 

 (The world's total supply of concentrated radium 

 amounts to only a few pounds.) If an aviator had flown 

 through the mushroom and inhaled its air, he would 

 probably have died as a result. If an aviator's plane 

 had failed and he had been forced to jump, his para- 

 chute w^ould have been of little avail if it carried him 

 into this cloud. 



The mushroom's menace was a lingering one. Its 

 fission products settled out very slowly, endangering 

 everything lying in its path. The menace became the 

 more insidious when, about one hour after the explo- 

 sion, the cloud lost its characteristic shape and became 

 visually indistinguishable from other clouds in the 

 area. 



Airmen continued to track it for many hours in 

 B-29 planes carrying Geiger counters ; they found that 

 the affected air region followed the course predicted 



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