Thomas Godfrey (January 10, 1704 – December 1749) was a

glazier A glazier is a tradesperson responsible for cutting, installing, and removing glass (and materials used as substitutes for glass, such as some plastics).Elizabeth H. Oakes, ''Ferguson Career Resource Guide to Apprenticeship Programs'' ( Infoba ...

and self-taught mathematician and astronomer in the Pennsylvania Colony, who invented the octant in 1730. A similar octant was also independently invented about the same time by

John Hadley John Hadley (16 April 1682 – 14 February 1744) was an England, English mathematician, and laid claim to the invention of the octant (instrument), octant, two years after Thomas Godfrey (inventor), Thomas Godfrey claimed the same. Biograp ...

in London with Hadley receiving the greater share of the credit for development. He published

almanacs An almanac (also spelled almanack and almanach) is a regularly published listing of a set of current information about one or multiple subjects. It includes information like weather forecasting, weather forecasts, farmers' sowing, planting dates ...

and contributed essays on mathematics, astronomy and general topics to the ''

Pennsylvania Gazette ''The Pennsylvania Gazette'' was one of the United States' most prominent newspapers from 1728 until 1800. In the years leading up to the American Revolution, the newspaper served as a voice for colonial opposition to Kingdom of Great Britain, ...

'' and '' Pennsylvania Journal''. He assisted the Welsh surveyor Lewis Evans in conducting astronomical observations to correct the longitude of Philadelphia on maps published by Evans. He was friends with

Benjamin Franklin Benjamin Franklin (April 17, 1790) was an American polymath: a writer, scientist, inventor, statesman, diplomat, printer, publisher and Political philosophy, political philosopher.#britannica, Encyclopædia Britannica, Wood, 2021 Among the m ...

and a founding member of the Junto club, which was the precursor of the

American Philosophical Society The American Philosophical Society (APS) is an American scholarly organization and learned society founded in 1743 in Philadelphia that promotes knowledge in the humanities and natural sciences through research, professional meetings, publicat ...

. He served as a director of the

Library Company of Philadelphia The Library Company of Philadelphia (LCP) is a non-profit organization based on Locust Street in Center City, Philadelphia, Center City Philadelphia. Founded as a library in 1731 by Benjamin Franklin, the Library Company of Philadelphia has a ...

and was a member of American Philosophical Society with the title "mathematician".

Early life

Godfrey was born January 10, 1704, to Joseph and Catherine Godfrey on the family farm in

Bristol Township, Philadelphia County, Pennsylvania Bristol Township was a township that was located in Philadelphia County, Pennsylvania, United States. The township ceased to exist and was incorporated into the City of Philadelphia following the passage of the Act of Consolidation, 1854. It is the ...

. His father died when he was 1 years old and he inherited the family farm at age 21. He moved to Philadelphia and worked as a plumber and a

. He installed the glass in Philadelphia's State House, now

Independence Hall Independence Hall is a historic civic building in Philadelphia, where both the United States Declaration of Independence, Declaration of Independence and the Constitution of the United States were debated and adopted by the Founding Fathers of ...

. He was employed at the estate of James Logan who encouraged Godfrey to pursue mathematics and science. He became a

deist Deism ( or ; derived from the Latin term '' deus'', meaning "god") is the philosophical position and rationalistic theology that generally rejects revelation as a source of divine knowledge and asserts that empirical reason and observation ...

Career

While working at James Logan's estate,

Stenton Stenton () is a parish and village in East Lothian, Scotland. It is bounded on the north by parts of the parishes of Prestonkirk and Dunbar, on the east by Spott and on the west by Whittingehame. The name is said to be of Saxon derivation. T ...

, Godfrey observed a reflection in a piece of broken glass which prompted the idea for the reflecting quadrant. Godfrey accessed a copy of

Isaac Newton Sir Isaac Newton () was an English polymath active as a mathematician, physicist, astronomer, alchemist, theologian, and author. Newton was a key figure in the Scientific Revolution and the Age of Enlightenment, Enlightenment that followed ...

's ''

Philosophiæ Naturalis Principia Mathematica (English: ''The Mathematical Principles of Natural Philosophy''), often referred to as simply the (), is a book by Isaac Newton that expounds Newton's laws of motion and his law of universal gravitation. The ''Principia'' is written in Lati ...

'' in Logan's library to further expand his idea. While challenged by the Latin text, with Logan's support, he was able to learn Latin and apply Newton's theories to his idea. Godfrey began experiments to develop an improved quadrant for determining

latitude In geography, latitude is a geographic coordinate system, geographic coordinate that specifies the north-south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from −90° at t ...

for navigation. He carried out much of his work in part of a home he rented from

. Godfrey completed development of his octant in 1730 and the accuracy of the device was tested by the captain and first mate of the ''Trueman'' on voyages to the West Indies and Newfoundland. James Logan sent a description of Godfrey's invention to

Edmond Halley Edmond (or Edmund) Halley (; – ) was an English astronomer, mathematician and physicist. He was the second Astronomer Royal in Britain, succeeding John Flamsteed in 1720. From an observatory he constructed on Saint Helena in 1676–77, Hal ...

, the

Astronomer Royal Astronomer Royal is a senior post in the Royal Households of the United Kingdom. There are two officers, the senior being the astronomer royal dating from 22 June 1675; the junior is the astronomer royal for Scotland dating from 1834. The Astro ...

in Britain. Logan was surprised to then see an almost identical device described as invented by

in the ''

Philosophical Transactions of the Royal Society ''Philosophical Transactions of the Royal Society'' is a scientific journal published by the Royal Society. In its earliest days, it was a private venture of the Royal Society's secretary. It was established in 1665, making it the second journ ...

''. Hadley received a patent for the octant in 1734 without contest. Godfrey, along with Logan, wrote to the Royal Society to defend his claim that the device was his original invention. The communication including sworn affidavits signed by the Mayor of Philadelphia that Godfrey's octant was crafted by Edmund Woolley of wood on November 1730. The communication also noted that Hadley's nephew was present at an early demonstration of his invention. His claim was denied, but he did receive a cash reward for his work from the Society. From 1729 to 1736, Godfrey worked as a publisher of almanacs. He also contributed essays on mathematics, astronomy and general topics to the ''

'' and '' Pennsylvania Journal''. He assisted Lewis Evans in conducting astronomical observations to correct the longitude of Philadelphia on maps published by Evans. Godfrey was a founding member, with Benjamin Franklin, of the Junto club, which was the precursor of the

. Godfrey was a director of the

and was a member of American Philosophical Society with the title "mathematician". Franklin described Godfrey at length in his ''

Autobiography An autobiography, sometimes informally called an autobio, is a self-written account of one's own life, providing a personal narrative that reflects on the author's experiences, memories, and insights. This genre allows individuals to share thei ...

'': Godfrey died in 1749 at the age of 45. He was originally interred at his farm near Germantown, but over time the grave fell into disrepair. In 1838, John Fanning Watson reinterred the remains of Godfrey, his wife, father and mother to

Laurel Hill Cemetery Laurel Hill Cemetery, also called Laurel Hill East to distinguish it from the affiliated West Laurel Hill Cemetery in Bala Cynwyd, Pennsylvania, Bala Cynwyd, is a historic rural cemetery in the East Falls, Philadelphia, East Falls neighborhood ...

. In 1843, a memorial erected by the Mercantile Library Company of Philadelphia was placed atop their graves.

Personal life

Godfrey was married and had five children. His second son, also Thomas Godfrey, was a poet and published several popular works, including the play ''

The Prince of Parthia ''The Prince of Parthia'' is a Neo-Classical tragedy by Thomas Godfrey and was the first stage play written by an American to be presented in the United States by a professional cast of actors, on April 24, 1767, at the Southwark Theatre in P ...

''.

References

{{DEFAULTSORT:Godfrey, Thomas (inventor) 1704 births 1749 deaths 18th-century American inventors 18th-century American mathematicians 18th-century American astronomers 18th-century American artisans 18th-century American engineers Almanac compilers 18th-century American writers American deists American plumbers American publishers (people) American scientific instrument makers Burials at Laurel Hill Cemetery (Philadelphia) Date of death unknown Glaziers Independent scientists Members of the American Philosophical Society People from Philadelphia People from colonial Pennsylvania Scientists from Philadelphia Inventors from Pennsylvania