Any Compass experts ?

[Blister]

Any Compass experts ?

I have this unit and know absolutely NOTHING about it

I assume the red pointer is north

It also has these markings on the lid

any ideas what it means ??

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It has a mirror inside the lid with a fine marker line running top to bottom and a hole to look through ? at the base of the mirror

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Also it has a leaver recessed into the base when you move it , it moves the part in the bottom of the compass with marking on it / spirit level

Its very well made but has no makers name on it , Comes with a small key to fit into a screw slot on the outer rim ???

I'm stumped

 

[Harbo]

This might help?

http://www.avestaca.com/category.cfm?Category=3

Rod

 

[Chrisnw]

That is a prismatic compass used for visual navigation. It allows you to hold the compass up to your eye and read the bearing through the prism whilst also using the sight to look at a point in the distance, or to let you take a magnetic bearing by aiming at a points and then noting the bearing.

Very similar to a sighting compass which doesn't have the prism but instead has a magnifiying glass to look at the bearing, though this does mean you have to take it down from your eye to view. The easiest way to tell the difference is that a sighting compass won't have mirrored numbers.

There is a description of how to use one here

http://www.trademarklondon.com/resource ... TIONSa.pdf

Though since a picture paints a thousand words:

http://www.youtube.com/watch?v=fM2eHJF12OM - a modern day version but you can see how to 'aim' the compass

http://www.youtube.com/watch?v=SzCFqnzt ... re=related - for a sighting compass but you should get the idea.

Chris