In February 1954 preparations were made on Bikini Atoll for the explosion of a hydrogen bomb. March 1 was the “ready” date. It did not seem probable that the shot would actually be fired on that date because the shot could be fired only under quite favorable wind conditions. Large amounts of radioactivity, especially fission products, were expected from the explosion. The shot could be fired only if no inhabited places lay in the downwind direction. Bikini is an oval-shaped coral reef, an atoll. It is one of several such atolls belonging to the group called the Marshall Islands. If you look at the map, you will see that west of Bikini at a distance of 200 miles lies Eniwetok, on which our people were making preparations for further tests. To the east of Bikini, a hundred miles or so, is Rongelap Atoll. At that time 64 people were living there. They lived primitively in palm houses on the southern part of the atoll. The northern part was uninhabited. On nearby Ailinginae Atoll 18 of the Marshallese islanders were on a fishing expedition, while farther to the east on Rongerik 28 American servicemen were stationed. The servicemen lived and worked in aluminum huts. Their main job was to collect weather data. [Illustration: Map of the Marshall Islands] Much farther to the east, 300 miles from Bikini, is Utirik. One hundred and fifty-seven Marshallese people lived on this atoll. Early on the morning of March 1, a Japanese fishing boat lay somewhere to the north of Rongelap. Her name was Fukuryu Maru, which means in English the Fortunate Dragon. There were 23 men on board. Actually she was in a patrolled zone but had not been sighted by the patrol aircraft. Operations for the test were being directed from ships of Joint Task Force 7. For several days prior to the morning of March 1, the weathermen had been mapping the winds. A wind to the west would be bad for Eniwetok. A wind to the east might hurt Rongelap and Rongerik. A wind to the south could affect Kwajalein. The ideal direction would have been due north, but this probably would not happen for months. On “shot” morning the wind was blowing to the northeast. The meteorologists gave their “O.K.” It was at dawn, the first of March, 1954. The firing crew of nine people led by a man of considerable experience, Jack Clark, were responsible for the final arrangements. They were in a blockhouse on the south side of the atoll 20 miles from the bomb. Others, more than 1000 people, watched from shipboard under the direction of Al Graves, who was responsible for the technical phases of the operation. The ships lay south and a little east of Bikini. The firing mechanism was set into operation in the blockhouse. One after another signals indicated that the various experiments and observations were set to work. Finally a red light went off and a green light appeared on the panel. This meant that the bomb had been detonated.