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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Big fat sunspot and a solar eclipse
From: Bill Morris
Date: 2014 Oct 24, 17:56 -0700
From: Bill Morris
Date: 2014 Oct 24, 17:56 -0700
Well before Cook's time there were filar micrometers, in which a micrometer moved one or more wires in the field of view of a telescope to measure angular separations of objects. The split lens principle was used in Stuart's Marine Distance meter, made by Henry Hughes and Son. Read about it here: http://sextantbook.com/2012/07/
Bill Morris
Pukenui
New Zealand
