NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Help W French Surveying Compass With Altitude??
From: Joel Jacobs
Date: 2005 Apr 27, 14:10 +0000
From: Joel Jacobs
Date: 2005 Apr 27, 14:10 +0000
Hello Group,
I have a very nicely made French compass that I think is supposed to read vertical angles that has a scale that I think allows for calculating the distance "off". Unfortunately, I don't read French, and even if I did, I am not sure that I would understand how you get the small brass pendulum to work so as to read the angle, if in fact that is what the pedulum does.
The compass card with the scales are printed in reverse. For a bearing, you view through the black sighting vane with your line of vision into a circular mirror in which you see the compass card in proper orientation, and through a clear slit in the mirror which acts as the forward sighting vane you select the target. There is what I take to be a brass pendulum which will point to a scale, but to do this, the case has to be placed sideways. Doing that makes viewing through the sighting vane impossible.
Pictures and instructions in French may be found at http://www.villagephotos.com/pubbrowse.asp?folder_id=1310102
Your help, as always, will be appreciated. Thanks,
Joel Jacobs