John M. MacKeigan

John M. MacKeigan | ASCRS

2000 to 2001

I wish to thank the Society for the privilege of standing before you today, and for the wisdom to place this presentation before lunch. It gives me reassurance that if the hall should empty during this presentation, it has nothing to do with the quality of the talk, but more to do with the quality of the lunch.


Today, I would like to talk to you about longitude- finding longitude. We are all navigators; we are pilots sailing our own vessels--explorers launched into uncertain realms in uncertain times--at a time when our profession and the value of our professionalism is constantly being questioned. But let us not give up hope. Francis Bacon wrote in the Advancement of Learning: "They are all discoverers that think there is no land, when they can see nothing but sea." During the early 1700s, the age of exploration, navigation was treacherous. Ships went aground frequently, and ships were literally lost at sea as soon as they lost sight of land.


Dava Sobel in her book Longitude tells the stow of navigation, of scientific discovery and independence, of politics and its influence on independent thought, discovery, and the seeking of new worlds. As you know, the latitudes are the parallel lines encircling the globe, fixed, for the most part, by the laws of nature. The longitudes, in contrast, were set by politics as well as by science. The placement of the 0 ° longitude, the Prime Meridian--where east meets west--was purely a political decision.