A sextant is a doubly reflecting navigation instrument used to measure the angle between any two visible objects. The principle of the instrument was first implemented around 1730 by John Hadley (1682–1744) and Thomas Godfrey (1704–1749) but it was also found later in the unpublished writings of Isaac Newton (1643–1727).
This is the horizon mirror and a shade glass from my father's sextant, backlit by an LED torch.
HMM! Hope you have a good start for the new week. Thanks, as always, for stopping by and for your kind comments, awards and faves -- I appreciate them all.
© Melissa Post 2017