One of our students, Yutaka, went to Greenwich this weekend, expressly to bestride the Prime Meridian at the Royal Observatory.
He needn’t have bothered. If he really wanted to bestride meridians he could just as well have taken a bus to Bar Hill or Comberton and walked out into the fields to the east of Cambridge, across which the Meridian passes (the longitude of OISE, out of interest, is 0.132969, or 0 degrees, 7 minutes, 49 seconds).
The Meridian, which marks 0 degrees longitude and is the basis for universal time, was in the nineteenth century located in various parts of the world as convenience dictated, but was unified at Greenwich, site of the Royal Observatory, in a conference held in Washington DC in 1884, largely because of Britain’s dominance as a maritime nation at that time (a number of countries held out, including France, which continued to use the Paris Meridian until 1911).
The Meridian runs through various countries north to south (England, France, Spain, Algeria, Mali, Burkina Faso, Togo, Ghana, and Queen Maud Land in the Antarctic). Another student in Yutaka’s class last week, Javier, says that just outside Pamplona where he lives there is a bridge bisected by the Meridian – driving over it is, conventionally and in imagination, swapping hemispheres.
Perhaps Yutaka was right to go to Greenwich and not to the fields near Bar Hill. I haven’t been for years, but I remember enjoying the sense of place (Greenwich has much to offer besides the Royal Observatory, in fact – not least the National Maritime Museum and the Cutty Sark). Apart from anything else, Greenwich makes for a better photo opportunity.