CHAPTER 11

Nuclear Weapons

At 5.30 a.m. an the morning Of 16th July, 1945, in the remote Alamagordo area of the desert wastes of New Mexico, the first nuclear explosive system ever developed by mankind was mounted at the summit of a steel tower and successfully detonated by means of a robot timing-control mechanism.
    At the instant of explosion an intensely hot, blinding flash illuminated the whole trials site; the steel tower was transformed instantaneously into vaporous form and vanished into the huge, seething, multi-coloured cloud of gaseous matter which surged skywards to an altitude of nearly 40,000 feet. In the target area, the normally infusible desert sand was blasted, melted and scorched into a blackened, glassy crater and from this devastated centre an explosive pressure wave of great destructive power billowed outwards with a tremendous roar.
    A few months later weapons of this nature were employed in World War II against the cities of Hiroshima and Nagasaki. These bombs are stated to have an explosive energy approximately equivalent to that of 20,000 tons of a conventional explosive such as trinitrotoluene (T.N.T.) and are frequently referred to as "nominal" or "20' kiloton" atomic weapons.
    With the cessation of hostilities, the British and Commonwealth scientists, who had collaborated so fully and ably with the United States  Atomic Weapons Organization, returned to Britain and became a highly specialized nucleus for the development of a similar organization in the "Mother Country". In October, 1952, near the Montebello Islands, which lie off the western coast of Australia, the first nominal United Kingdom atomic weapon, designed and developed by Dr. Penney (now Sir William) was successfully detonated aboard the naval frigate Plym. Other British weapons and weapon devices have also been tested more recently in the desert regions of South Australia and an the Montebello Islands.
    On 1st March, 1954, at the Bikini Atoll, and on 21st May, 1956, the U.S.A. are reported to have successfully exploded nuclear devices with a power equivalent to many million tons (megatons) of T.N.T. The Russian test of October, 1955, is also believed to have involved a nuclear device which gave explosive yields in the megaton range. Thus, within a decade nuclear weapons have been developed which have many hundreds of times the explosive power of the earliest weapon devices.
    There has been considerable speculation both in the Press and in scientific literature as to the manner in which these mammoth releases of energy have been achieved and what constitutes the essential difference between kiloton and megaton weapons. The most common terminological

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