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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Vernier explanation
From: Frank Reed
Date: 2022 Jun 27, 07:29 -0700
From: Frank Reed
Date: 2022 Jun 27, 07:29 -0700
Peter Monta, you wrote:
"Hmm. Could the vernier have been mis-engraved, perhaps by configuring the dividing engine with settings intended for the arc? How would that have gotten past final quality control?"
It's possible, and I have had the same thought. Antique things survive for many reasons, and one potential cause is "unsellable stock". This is a last resort explanation, but when everything else is ruled out... that's it.
Note also that the sextant can be read by visual interpolation on the main arc to about +/-2 minutes of arc. That's good enough for most practical celestial navigation (excluding exotica, like lunars).
Frank Reed
