BOMBS AT BIKINI 



the shock wave expanded, it smoothed out the bend 

 and in short order assumed nearly hemispherical 

 shape. 



Both the underwater shock wave and the air shock 

 wave left their circular marks on the surface of the 

 lagoon. The water shock disk expanded very rapidl,y; 

 the air shock disk expanded more slowly and showed up 

 more clearly in the photographs. 



The shock wave reflection effects were remarkably 

 vigorous. Slow-motion pictures show the strange pat- 

 terns produced on the surface by the underwater reflec- 

 tion of the water shock wave. They show also the typical 

 effect produced when the air shock wave struck one of 

 the inner ships: the localized reflection created a new 

 spherical wave spurting out in many directions. Ac- 

 tually, it was not the secondary shock wave itself 

 which was photographed, but the secondary conden- 

 sation cloud which was pursuing the secondary shock 

 wave. 



The primary condensation cloud Avas tremendous, 

 covering an area of roughly six square miles. It had 

 started forming within one second of Mike Hour; one 

 or two seconds later it had reached the "birthday cake 

 on a platter" stage. But it evaporated very rapidly. 

 Within eighteen seconds after Mike Hour it had the 

 form of a hollow ring, and almost immediately there- 

 after it broke up and disappeared. A small conden- 

 sation cap formed momentarily directly above the 

 cauliflower; it lasted only a few seconds. 



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