A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Igor S.
Date: 2020 Mar 19, 16:35 -0700
Looks like HYDROGRAPHIC SURVEY SEXTANT ON STAND http://www.westsea.com/captains-log/evolutionofthesextant.html
see also https://colnect.com/en/stamps/stamp/443977-Sextant_19th_Century_Detail_of_a_Map_of_Livingston_Island-10_Years_Bulgarian_Antarctic_Cartography-Bulgaria
It seems from the photo that the shade glasses are not used !