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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Mysterious celestial measurement
From: Luc Van den Borre
Date: 2016 Jul 1, 16:50 +0200
From: Luc Van den Borre
Date: 2016 Jul 1, 16:50 +0200
On 01/07/16 15:43, Ed Popko wrote: > What could this person possibly be measuring? Artistic license for sure. Looks pretty ok to me! It's a Jacob's staff with three cross pieces. He seems to be sliding the first piece against a scale on the staff. The other sliders don't obstruct his view of the bottom and top of the first cross piece. What a bother it is to remove them if one doesn't need to! In the dark you'd probably step on one and break it. He's holding it in a reasonable way, I think. Search for 'radius astronomicus'. The idea of the different sliders is to increase the range of the instrument. A smaller slider can measure smaller angles against the same scale drawn on the stick. http://www.dehilster.info/navigational_instruments/1661_kronan_cross-staff.php Luc
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