James Blanchard-O'Brien
James Blanchard-O'Brien answered
If Hadley and Godfrey both invented the octant (the predecessor to the sextant) in 1730, though Newton actually had it in 1699, though his publisher Halley, did not get it published until 1742. It is doubtful that the sextant was developed in under a year, because Caleb Smith,had created an octant in 1734.He called it … Read more