John Hadley 1682 - 1744
- Nationality:
- British; English
- born in:
- Bloomsbury, Camden, London, Greater London, England, United Kingdom
A member of the Royal Society, he is known for his improvements to the reflecting telescope, being the first to construct a catadiopic system to the Gregorian design. He is also associated with the design of the octant a navigational instruments formerly known as the Hadley quadrant after its inventor