Celestial Navigation · Sextant — Care and Reading
Good practice in handling a marine sextant includes:
- ACleaning the mirrors with sandpaper
- BLifting it by the index mirror
- CHolding it by the frame/handle, protecting the mirrors and arc, and stowing it in its case✓ Correct
- DLeaving it loose on deck
Explanation
The sextant is a precision instrument: handle it by the frame or handle, never by the mirrors, telescope, or arc; keep the optics clean with proper materials; and return it to its padded case. Rough handling introduces or worsens instrument errors.
Authority: Bowditch (Pub. No. 9), The Marine Sextant
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