Dr. David MacVeigh, a member of Teignmouth Probus Club presented an illustrated talk about The History of Navigation or “Where the Hell are we?” from explorers who set off not knowing where they were going to navigators who knew where and how to get there.

The creation of Maps of land, charts of the sea and use of celestial bodies have been around for millennia, particularly old civilizations such as the Sumerians and Babylonians. Progress was made with the ingenuity of man making new ‘invention’, from a simple compass to determine ‘North’, accurate charts (Royal Navy), the sextant (developed from the Davis Quadrant 1759), new accurate timepieces (Harrison 1730’s), through to present day satellite technology of GPS and computer programme.

Our story started with Ptolemy of Alexandria (150 AD ) with maps showing lines of longitude showing vertical lines north to south based on one twelfths mathematics or one degree of 360° circle, and latitude the horizontal lines plotting our sun’s circular path the centre being the equator. Latitude can be determined by the relationship of the horizon to the sun and stars using a sextant and nautical almanacs (Royal Observatory 1767), but longitude was more guesswork by ‘dead reckoning’.

A Royal Navy disaster with huge loss of life because a miscalculation of position, led to The Longitude Act of 1714 with the Government offering a prize of £20,000 (£2 million+ in today’s money) brought great minds together to find a way of accurate longitudinal positioning. Great innovation followed led by Harrison’s Marine Chronometer and Sir Nevil Maskelyne, 5thAstronomer Royal, in the 1770’s found a way to calculate longitude with the accurate use of timekeeping.

The world dominance of the British Royal Navy for accurate chart making, Harrison’s chronometer and the work of the Greenwich Observatory, in 1884 led to establishing world standard time being that of Greenwich (Greenwich Mean Time – GMT) and to be the centre of Zero meridian. A precise position could then be made to know almost exactly your position on the globe.

This history was demonstrated by the problems facing Polynesian sailors intuition using stars, Christopher Columbus in 1490’s, Ferdinand Magellan 1st circumnavigation and West Indies adventures in 1520’s and Sir Francis Drake South 2nd circumnavigation and South American exploits 1570/80’s. Today, we can navigate anywhere in the world to a 3 metre square from our smartphone with Google Earth and What Three Words.

Member Peter Lewis gave the vote of thanks commenting on the brilliance and ingenuity of the human mind.

Posted by Rick Purnell Press Officer