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Polaris missileThe Polaris is a ballistic missile carrying a nuclear warhead. It was the first submarine-launched ballistic missile (SLBM).Lockheed developed it as a solid fuel Fleet Ballistic Missile (FBM) for the US Navy. The first successful test flight was from Cape Canaveral on January 7, 1960. The nuclear warhead was developed at the (now) Lawrence Livermore National Laboratory by a team headed by Harold Brown from 1957. In July 1960, the Navy accepted delivery of the first 16 warheads and on November 15 the first Polaris missile was test launched from a submarine. The missile was 12.3 meters (40.5 feet) long and with a finspan of 2.6 meters (8.5 feet) and capable of delivering a 1MT warhead 4000km. The USS George Washington was the first fleet ballistic missile submarine, carrying sixteen missiles. From 1960 to 1966 a further forty SSBNs were launched. The missile began to be replaced by Poseidon beginning in 1972, in in the 1980s both were replaced by the Trident I.
British PolarisThe British use of Polaris stems from the failure of the Blue Streak missile and the cancellation of the Skybolt project in the 1950s. Harold Macmillan and John F. Kennedy agreed at the 1962 Nassau Conference[?] that the United States would supply Britain with Polaris. America would supply the missiles, the launch tubes and the fire control system, while the warheads and submarines would be British made. In return America was given certain assurances by Britain regarding the use of the missile. The Polaris Sales Agreement was signed on April 6, 1963. The British Polaris submarines were the Resolution Class Ballistic Missile Submarines. The Polaris system underwent a significant, British designed, life extension programme called Chevaline, which among other things doubled the number of warheads deployed by the Polaris system. The British evetually upgraded to the Trident missile after much political wrangling over the cost and necessity, but waited for the Trident II (D5) variant. See also: Program Evaluation and Review Technique As ants work by inherited instincts
manufactured instruments, a perfect division of labour.html">labour could be
been fertile, they would have intercrossed, and their instincts and
effected this admirable division of labour in the communities of ants,
with all my faith in this principle, I should never have anticipated
had not the case.html">case of these neuter insects convinced me of the fact. I
insufficient length, in order to show the power of natural selection,
difficulty, which my theory has encountered. The case, also, is very
amount of modification in structure can be effected by the
variations, which are in any manner profitable, without exercise or
volition, in the utterly sterile members of a community could possibly
alone leave descendants. I am surprised that no one has advanced this
of Lamarck.
SUMMARY.
I have endeavoured briefly in this chapter to show that the mental
inherited. Still more briefly I have attempted to show that instincts
are of the highest importance to each animal. Therefore I can see no
accumulating slight modifications of instinct to any extent, in any
come into play. I do not pretend that the facts given in this. All is still licensed under the GNU FDL.
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