The Mary Celeste - Facts not fiction

Its a matter of time ...

You may notice that its reported in the text that the 'Mary Celeste' was sighted by the 'Dei Gratia' on one date in the text, and another on the chart. the reality is it was first seen on both the 4th and 5th December;

This anomaly is explained by the fact that their record keeping was based on "Civil Time", presumably EST of the day and also "Sea Time", the celestial time of the ships current location.

Prior to 1920, all ships kept solar time on the high seas by setting their clocks at night or at the morning sight so that, given the ship's speed and direction, it would be 12 o'clock when the sun crossed the ship's meridian.

It would of course have been easier to express times in GMT, however that was not adopted as a world standard until 1884 when U.S. President Chester A. Arthur convened the International Meridian Conference

Delegates from 21 nations met in Washington, D.C., to determine a globally recognised location for the prime meridian, and with it, a worldwide standard for time zones.

Support for the meridian to be located in Greenwich, England, was overwhelming, because a vast majority of the world's shipping was already dependent on nautical maps that used Greenwich as 0 degrees longitude.

The vote for Greenwich was nearly unanimous; only San Domingo voted against, with France abstaining.

A time zone standard was set with a one-hour time change every 15 degrees of longitude, with Greenwich Mean Time as the reference point. The time zones called for every 15 degrees east of the prime meridian to be an hour earlier than the time at Greenwich, and every 15 degrees west of the prime meridian to be an hour later.

Despite this, the establishment of nautical standard times, nautical standard time zones and the nautical date line were only finally agreed by the Anglo-French Conference on Time-keeping at Sea in 1917.

GMT is based on mean solar time (at Greenwich, UK) and has since been replaced by UTC based on quantum resonance and a consensus of clock keepers.

Click on the links above for more information about time.