September 18, 2012

Demystifying celestial navigation

IN THE DAYS before GPS, navigators were much sought-after on deep-sea racing yachts. Many thought themselves to be mighty fine fellows, and strutted around like minor royalty with their charts and sextant boxes tucked under their arms. They maintained a high hedge of mystique around the art of celestial navigation.

Then, in 1950, along came a woman called Mary Blewitt who mowed down their hedges and called their bluff. She wrote a modest 60-page book called Celestial Navigation for Yachtsmen that showed everyone how to find their position at sea with no more math than a few simple additions and subtractions.

That book is still in print but I expect sales are down now. There’s not much call for celestial navigation when you can get your position in an instant by pushing a button on a GPS receiver.

But if you want to experience the sheer pleasure and profound satisfaction of handling a precision instrument to measure the sun and the stars and plot your position on the chart like centuries of seamen before you, clutch Mary Blewitt to your heart. Then you, too, will be entitled to strut your stuff.

Incidentally,  you can practice taking sights with your sextant at home by shooting the sun in a tray of old engine oil or an artificial horizon.

Today’s Thought
There is no greater disloyalty to the great pioneers of human progress than to refuse to budge an inch from where they stood.
— Dean W. R. Inge.

Tailpiece
“Excuse me waiter, how long how you been working here?”
“Only about a week, sir.”
“Oh, you can’t be the one who took my order, then.”

(Drop by every Monday, Wednesday, Friday for a new Mainly about Boats column.)

2 comments:

KevinH said...

Yup, all you need is Mary Blewitt and a Davis or Ebbco plastic sextant and the world is your oyster so-to-speak. Did me just fine all the way around the world.
Well,OK, you also need sight reduction tables, a quartz watch and occasional time checks.

John Vigor said...

Well done, KevinH. Plastic and Blewitt is obviously a great combination.

John V.