Joseph Saxton was an American

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 inventor, born at Huntingdon

Huntingdon, Pennsylvania

Huntingdon is a borough in Huntingdon County, Pennsylvania. It is the county seat of Huntingdon County. It is located along the Juniata River, west of Harrisburg, about halfway between Pittsburgh and Harrisburg, in an agricultural and fruit-growing region, with valuable forests and deposits of...

, Pa.

Pennsylvania

The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...

  He went to Philadelphia

Philadelphia, Pennsylvania

Philadelphia is the largest city in the Commonwealth of Pennsylvania and the county seat of Philadelphia County, with which it is coterminous. The city is located in the Northeastern United States along the Delaware and Schuylkill rivers. It is the fifth-most-populous city in the United States,...

 in 1817 and while there invented a machine for cutting the teeth of marine chronometer

Marine chronometer

A marine chronometer is a clock that is precise and accurate enough to be used as a portable time standard; it can therefore be used to determine longitude by means of celestial navigation...

 wheels, and an escapement

Escapement

In mechanical watches and clocks, an escapement is a device that transfers energy to the timekeeping element and enables counting the number of oscillations of the timekeeping element...

 and compensating pendulum for clocks, and constructed a clock for the steeple of Independence Hall.

He went to London

London

London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

 in 1828 and resided there nine years, enjoying the acquaintance of Faraday

Michael Faraday

Michael Faraday, FRS was an English chemist and physicist who contributed to the fields of electromagnetism and electrochemistry....

. On his return to Philadelphia he superintended the making of machinery for the United States Mint

United States Mint

The United States Mint primarily produces circulating coinage for the United States to conduct its trade and commerce. The Mint was created by Congress with the Coinage Act of 1792, and placed within the Department of State...

 and afterward had charge of the construction of standard weights and measures, accurate sets of which were furnished to national and State governments. Among his ingenious contrivances may be mentioned a mirror comparator

Comparator

In electronics, a comparator is a device that compares two voltages or currents and switches its output to indicate which is larger. They are commonly used in devices such as Analog-to-digital converters .- Input voltage range :...

 for comparing standards of length and a new form of dividing engine

Dividing engine

A dividing engine is a device specifically employed to mark graduations on measuring instruments.-History:There has always been a need for accurate measuring instruments...

; a self-registering tide gauge

Tide gauge

A tide gauge is a device for measuring sea level and detecting tsunamis.Sensors continuously record the height of the water level with respect to a height reference surface close to the geoid...

, and an immersed hydrometer

Hydrometer

A hydrometer is an instrument used to measure the specific gravity of liquids; that is, the ratio of the density of the liquid to the density of water....

.

See also

• U.S. National Geodetic Survey
  U.S. National Geodetic Survey
  National Geodetic Survey, formerly called the U.S. Coast and Geodetic Survey , is a United States federal agency that defines and manages a national coordinate system, providing the foundation for transportation and communication; mapping and charting; and a large number of applications of science...