quote:

Magnetic and true north are another issue alltogether. Here's a good way to remember when to add or subtract variation. "True Virgins make dull companions, add whiskey." So you add west and subtract east. jorge

The way I was taught (in the RAAF) to remember how to apply magnetic variation was - "Variation east - Magnetic least; Variation west - magnetic best".

Bob

I learned it as "least in the East and Best in the West". Guess they didn't want us getting hung on on the whole virgin thing.

Older and cheaper modern compasses divide the Earth into as much as four or five zones, each requireing a specific compass to get accurate bearings. Today most top-class compasses have two zones, and the compass designed for northern hemisphere will work accurately in the sothern one for a considerable distance.
Let's say from Tanzania-DRC-Congo and up you should be ok with the northern compass.

Best way to conclude this post is if someone from the north brings their compass down here and we tested it against one of ours down and against a gps !

Jim Manion:
I could not agree with you more: however, I was not a squid, I was a proud member of the US Army from 1959-1972, as an infantryman; therefore, I have brushed much mud from my boots, enjoyed countless meals of C's, encountered many misguided people whom wished to cause harm to Mrs. Chick's favorite son. I learned my navigation after entering civvie street

Bryan

That is good news. Just watch out for squids who have gone civilian. You can easily recognize them-they are partial to white shoes and belts (the white thing apparently never leaves them), attend Elton John conserts, and are hooked on "The Home and Garden Channel".

In the Army, we were collectively known as "soldiers". The Navy, "seamen". I rest my case....

It points along the local field lines -- whatever they are in your local area.

There will be a deviation from true north (more likely affected more strongly by true south). There can be effects from local iron deposits. But the same thing is true in the north... my compass worked fine in South Africa.

What I found a bit confusing was that the sun traveled from east to west through the northern part of the sky...

Dan

Jim: You know what a penis and a submarine have in common? They are both full of Se...!

Now Bryan, we have to be fair. After all, the Navy wrote the book on separating the men from the boys. Last I heard, a high pressure water hose worked best.....