Foreword 



k lO MAN really saw what happened at Bikini. 



' ^ Approximately 42,000 persons, drawn from 

 the four corners of the globe, travelled thousands 

 of miles to stage and witness the tests. But an 

 atomic bomb defies scrutiny. It shuns publicity. 

 It shields its intense life-span in a flash of light 

 many times the brilliance of the sun. It dazzles 

 human eyes. It limits its life to a matter of mil- 

 lionths of a second. It enshrouds itself in a cloud. 

 And then it dies, mushrooming grotesguely to 

 high altitudes as if for a better view of the havoc 

 it has produced. 



Even if pent up beneath the surface of a la- 

 goon it resists observation. Where before it 

 blinded the eye here it succeeds in blinding the 

 mind. In a matter of seconds it tosses up a column 

 of tons of water higher than the Empire State 

 Building. It sinks ships in a moment and crushes 

 others into the deformed, stepped-on shape of a 

 child's bath-tub toy. Itself the result of man's in- 

 tellect, the bomb defies examination by its creator. 



And yet the Bikini tests were thoroughly ob- 

 served. Supplementing human onlookers were 

 10,000 instruments, and among them cameras, 

 constructed to record what the human eye could 

 never see. Cameras are inquisitive instruments 

 with long memories. In the field of atomic re- 

 search they are indeed star witnesses. Their story 

 may appear differently to the scientist and the 

 layman. But all may grasp its general significance. 



For those who attended the tests these photo- 

 graphs may serve as the lasting momento of a 

 unique experience. For those who did not they 

 should serve to provide perspective concerning 

 the atomic bomb, and give better knowledge of 

 one of the largest scale ventures in experiment 

 ever attempted by man. This foreword has been 

 written with that end in view, and to place Opera- 

 tion CROSSROADS properly in the history of 

 the bomb. 



Previous Bombs 



HRIOR to July 1946 three atomic bombs had 

 been detonated — one above the New Mexico 

 desert, two more above the Japanese cities of 

 Hiroshima and Nagasaki. For an already weaken- 

 ing Japan these bombs spelled defeat. The bomb- 

 ing of Hiroshima, on August 5, 1945 (Greenwich 

 Mean Time) constituted the first military use of 

 the bomb. Nagasaki was hit on August 9 (G.M.T.). 

 On August 14, only nine days after Hiroshima, 

 Japan surrendered unconditionally. 



Now it could be told . . . the "best-kept secret 

 of the war," the story of secret research in the 

 field of nuclear physics, the successful tapping of 

 the tremendous energy of the atom, the mass 

 production of materials to make use of this energy 

 in the form of a bomb. The perplexing language 

 of science dominated the columns of the daily 

 press. Laymen throughout the United States 

 scratched their heads and attempted to under- 

 stand. 



One thing was clear. The bomb constituted a 

 revolution in pre-existing concepts of tactics and 

 strategy. The tremendous striking power of the 

 single, unaccompanied bomber over Japan, taken 

 to be a reconnaissance weather plane by those on 

 the ground, was retold with each succeeding bul- 

 letin describing the doomed cities. But just how 

 much of a revolution did the bomb represent? No 

 one knew the answer to that question. 



Trinity Test 



It was true that Bomb Number One, the first 

 atomic bomb ever detonated by man, had been 

 exploded "under laboratory conditions." This was 

 the so-called Trinity Test, conducted in the great, 

 roofless laboratory of the New Mexico desert near 

 Alamogordo on July 16, 1945. The Trinity Test 

 had been observed by scientists, military observers 

 and by hastily-set up instruments. But the instru- 



