A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Gary LaPook
Date: 2015 Aug 28, 10:28 -0700
The Russian SNO-T sextant comes with two little "L" shaped pieces that are used like the cylinders for checking the sextant mirror. See the manual for this sextant that I posted before at:
This translation calls them "diopters" and their use is explained on page 13 and 14.