Early (1600-1700s) Carved Navigational Sextant Component with Angles and MonogramI really love measuring tools of all sorts, and know there are a few of you out there who do, too and this is such an old one, I could not resist. I am quite sure it is a piece of a navigational instrument, and believe part of a sextant, used to measure the angle between an astronomical object and the horizon for the purposes of celestial navigation. (A moveable arm, probably made of brass, would have attached to the corner from the back.) Really rare