NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Two 19th century octants & sympiesometer
From: UNK
Date: 2017 Mar 24, 11:34 -0700
From: UNK
Date: 2017 Mar 24, 11:34 -0700
As a public service after Dr. Davis' post, a sympiesometer is a barometer using air over a water column. This allows a reasonable size water barometer instead of a 10 meter water column with a vacuum over.
The first definition said that it was a precision barometer and that sounded optimistic so I found:
http://drkfs.net/WFpaper.htm
It's not easy making an accurate air over water barometer as the air is compressed as the water rises and the air volume increases with temperature. But, apparently with lots of correction factors, the accuracy can be well under 1 mB
Oh, and sympiesometer is a legal Scrabble word. I suspect there have been daily fights over that. :-)
Regards, Noell
