Abraham Sharp

Abraham Sharp ( * 1653 in Horton Hall, Little Horton, near Bradford, Yorkshire, baptized on June 1, 1653 in Bradford, † July 18, 1742 in Horton Hall, Little Horton ) was an English astronomer, mathematician and instrument maker.

Life

Sharp was the son of a wealthy farmer and merchant John Sharp and his wife Mary. After attending the Grammar School in Bradford, he became in 1669 an apprentice to a haberdasher in Bradford. Maybe he worked in the following years as a teacher of commercial arithmetic in Liverpool, from 1684 he held himself in any case in London, where he found a job with the Astronomer Royal John Flamsteed. He first worked in two phases for Flamsteed, first from 1684 to 1685 for a few months, then from August 1688 to the fall of year 1690. Flamsteed expressed highly of Sharp's work at the large mural quadrant, however, disparagingly about the fulfillment of daily duties.

After the end of the work at Flamsteed Sharp worked briefly for the science book and instrument dealer William Court. In February 1691 he accepted a position at the Royal Shipyard in Portsmouth. In 1694 he returned to Horton Hall, after his eldest brother had died.

By the end of his life he remained in Horton Hall, built instruments, corresponded with many scientists and resulted from calculations. One focus was working with his former employer Flamsteed. The resulting correspondence is largely preserved. Among other things, he built for Flamsteed a micrometer (1704), calculated positions of the moon and planets as well as extensive tables for the Historia coelestis and darkness created tables of Jupiter's moons. After Flamsteed's death, he corresponded with his assistant Joseph Crosthwait, helped with the new edition of the Historia coelestis Britannica ( 1725) and made star maps for the atlas coelestis ( 1729 ).

Sharp died on July 18, 1742 in Horton Hall, and was buried on July 21 in St. Peter's in Bradford, where his memory was erected later. Some of his instruments are preserved in the collections of Bolling Hall Museum in Bradford, the National Maritime Museum and the Science Museum.

The lunar crater Sharp is named after him.

Writings

• Geometry improv'd (London 1717) 1 By a large and accurate table of segments of circles, its construction and various uses in the Solution of several difficult problem. With Compendious Tables for finding a true proportional part, and Their Use in synthesis or any other Tables; exemplify'd in making out or Logarithms Natural Numbers from them, to sixty Figures, there being a table of them for all Primes to 1100, true to Figures 61.
• 2 A concise treatise of polyedra, or solid bodies of many bases, Both the Regular and others: To Which are added Twelve New ones, with various Methods of forming them, and Their exact Dimensions in Surds or species, and in Numbers.