[DOC] [TLE] Sextant - Wikipedia [PAR] 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 (16821744) and Thomas Godfrey 
..... The American Practical Navigator. Bethesda, MD: National Imagery and 
Mapping Agency... [DOC] [TLE] John Hadley - Wikipedia [PAR] John Hadley (16 April 1682  14 February 1744) was an English mathematician, 
and laid claim to the invention of the octant, two years after Thomas Godfrey... [DOC] [TLE] John Hadley | British mathematician | Britannica.com [PAR] British mathematician and inventor who improved the reflecting telescope, 
producing the first such instrument of sufficient accuracy and power to be useful 
in astronomy. ... In 1730, independently of Thomas Godfrey of Philadelphia, 
Hadley invented ... or a star, used in celestial navigation to determine latitude and 
longitude. [DOC] [TLE] Navigational Instruments @ Celestial Navigation [PAR] The main instruments mariners need for Celestial Navigation are the ... There are 
good pictures and history of the former at John Harrison and the Longitude 
Problem. ... information is Scientific Instruments of Medieval and Renaissance 
Europe. ... To complicate matters, American inventor Thomas Godfrey built one in 
1730,... [DOC] [TLE] Navigation at Sea, History of - important, system, marine, human [PAR] Some of the early instruments used to assist sailors in determining latitude ... 
Around 1730, an English mathematician, John Hadley (16821744), and an 
American inventor, Thomas Godfrey (17041749), independently invented the 
sextant. [DOC] [TLE] Octant (instrument) - Unionpedia, the concept map [PAR] The backstaff is a navigational instrument that was used to measure the ... The 
era of European and American voyages of scientific exploration followed the ... 
John Hadley (16 April 1682 &ndash; 14 February 1744) was an English 
mathematician, and laid claim to the invention of the octant, two years after 
Thomas Godfrey... [DOC] [TLE] A Brief History of Navigational Instruments - TechnologyUK [PAR] Prior to the invention of the compass, navigators could establish their position 
and ... Descriptions of the most common type of compass used by European ..... 
John Hadley (1682-1744) and American inventor and optician Thomas Godfrey (
1704-1749), who invented similar instruments independently in around 1730. 
Hadley... [DOC] [TLE] Navigation - Sextant [PAR] The major problem with back-sight instruments was that it was difficult if not ... 
and almost simultaneously by John Hadley in England and by Thomas Godfrey, 
.... Early in the 1730s instrument makers began developing artificial horizons for 
use ... Around the base you can see the parts of the mercury bath artificial horizon
. [DOC] [TLE] (TB4BD86) Travel Octant Geocoin - Travel Octant ... - Geocaching [PAR] First North American Cache: titocache placed it in Santa Fe Trail Geocache #16 
... called reflecting quadrant, is a measuring instrument used primarily in 
navigation. ... credit for the invention that is generally given to John Hadley and 
Thomas Godfrey. Two men independently developed the octant around 1730: 
John Hadley... [DOC] [TLE] French Maritime Museum Navigation Instruments, Paris - Travel To Eat [PAR] Jul 28, 2012 ... They have a nice collection of navigational instruments at the ... The dry mariner's 
compass was invented in Europe around 1300. ... around 1730: John Hadley, an 
English mathematician, and Thomas .... Between 1800 and 1850 (earlier in 
British and French navigation practice, later in American, Russian,... [DOC] [TLE] Acceptance and adaptation of octants and sextants in Japan during ... [PAR] Around 1806, an octant was made for the first time in Japan. ... Octants were 
typical of the Western astronomical instruments imported directly from Europe to 
Japan, without ... They were invented nearly simultaneously by Thomas Godfrey 
of the US in 1730 (Hindle, 1972) and John Hadley of Britain in 1731 (Hewson, 
1951). [DOC] [TLE] Build a Sextant - MathinScience.info [PAR] The instrument commonly used in celestial navigation to measure altitude is the 
sextant. ... Later on, around 1730, two different men independently made 
improvements to the astrolabe, a device that resulted in

Question: This navigational instrument was invented around 1730 by John Hadley in Europe & Thomas Godfrey in America
Answer: Sextant