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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: The Blish prism and the sextant.
From: Russell Sher
Date: 2000 Jul 10, 8:13 AM
From: Russell Sher
Date: 2000 Jul 10, 8:13 AM
George, see this URL-- http://www.water-cooler.com/WC/patentviewer/patent-4428671.html It mentions a sextant attachment for determining Sextant out of True error. I read a mention of it in a Davis pamplet which came with their MK15 sextant. This URL also mentions Blish et. al.