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It is a curious tradition that the clock on the tower of Christ Church Cathedral in Oxford is always five minutes later than standard British time. The explanation for this lies in the conservative nature of the Cathedral's clergy_ It was only when the railways arrived in the middle of the nineteenth century that it became important for clocks throughout the country to be synchronised, however difficult this might be. When the Cathedral was asked to come into line, the clergy discussed the request but decided that this was an idea that needed to prove its worth before being adopted.