The history of Mankind's attempts to discover, or invent, the calendar is a fascinating one. Our day depends upon the time taken for the Earth to rotate about its axis, as observed from the rising and setting of the stars, particularly the sun. The month comes to us courtesy of the Moon's motion around the Earth. The year is based on the time taken by the earth to complete one orbit around the Sun. The calendar, then, is based on three distinct motions. As a result there is not, without manipulation, a whole number of days in a month or year, nor is there a whole number of months in a year.

Various strategies have been adopted to cope with the incompatibility of the measures. The ancient Egyptians ran more than one calendar simultaneously. Julius Caesar, on the advice of the Alexandrian astronomer Sosigenes, hit upon the idea of a Leap Year. Encyclopaedia Britannica tells us of the strategy adopted by the Yami fishermen of Betel-Tobago, near Taiwan. Their year is based on the moon. This means that their calendar gradually moves out of sync with the seasons. To combat this, the fisherman go out in their boats with lighted flares. If flying fish appear, the fishing season is allowed to commence. If however the lunar calendar is too far out of sync with the seasons, the flying fish do not appear. The response of the Yami is to postpone the fishing for a lunar month, which they insert into their calendar, thereby having a year of thirteen instead of twelve lunar months. Other civilizations have made use of non-astronomical signs to determine the seasons. In Mediterranean regions, the cry of migrating cranes meant it was time to plough and sow; whilst snails climbing up plants signalled an end to digging in the vineyards.

The contributions to the programme of Dr. Lipincott of the Old Royal Observatory and Dr. John Laverty of the National Physical Laboratory raise some interesting questions. Not least of which is 'What time is it, really?' Dr. Lipincott explains how periodically 'leap seconds' have to be inserted because the keepers of the Atomic clock have observed a slowing down in the Earth's rotation so a day becomes a 'a day and a slosh'. Furthermore if it is true that the earth's rotation is slowing down, then are we not really heading towards an Apocalypse, albeit different from the one in the Book of Revelation?