World adopts Greenwich Meantime
From the 17th century onwards Greenwich, home to the national observatory, had been the centre for the study of time as well as the skies, the link being the need for accurate timekeeping for navigation, which at that time was by the stars and the sun. Accordingly, a meridian at the Greenwich Observatory was set as the zero point of reference for determining time and longitude by the British.
As a nation of explorers and seafarers the British spread the use of the Greenwich meridian in navigation and time keeping. When the railway age took hold there was a need for a standard reference point for time for those travelling within the country as well as beyond it, thus the Greenwich meridian and Greenwich Mean Time was chosen in 1847 as the basis for railway timetables in the country. Greenwich Mean Time refers to the fact that because of variations in the earths elliptical orbit and axial tilt the sun may cross the meridian at Greenwich anything up to 16 minutes from the standard set for noon by Greenwich Mean Time.
In 1884 the US President called a conference of all those nations with which his country had diplomatic relations in order to determine a standard for world time keeping. The Washington conference decided on the meridian at Greenwich as the reference point (“the meridian passing through the centre of the transit instrument at the Observatory of Greenwich as the initial meridian for longitude” as the conference findings have it. Though San Domingo voted against this, and (surprise surprise) France and for some reason Brazil abstained, the resolution was passed.