NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Sextant Vernier Scale
From: Gary LaPook
Date: 2012 Mar 9, 17:40 -0800
From: Gary LaPook
Date: 2012 Mar 9, 17:40 -0800
You can prove it to yourself that this is a vernier that reads to 0.1'. Line up the upper mark, the one with the dot, with a mark on the drum. Now count down the marks on the drum and you will find that the tenth mark, the bottom line on the vernier, lines up with the eleventh mark on the drum. To show how this works turn the drum up slightly and the next mark on the drum will line up with the next mark on the vernier. continue slowly turning the drum and you will see that the marks line up consecutively on the drum and on the vernier. Then the last, the bottom, mark on the vernier lines up with a line on the drum you will see that the top mark, the one with the dot, on the vernier now lines up with the next mark on the drum. gl --- On Fri, 3/9/12, Scott <netbsd21@gmail.com> wrote:
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