John Speidell ( fl. 1600–1634) was an English mathematician. He is known for his early work on the calculation of logarithms.
Speidell was a mathematics teacher in London [1] [2] and one of the early followers of the work John Napier had previously done on natural logarithms. [3] In 1619 Speidell published a table entitled "New Logarithmes" in which he calculated the natural logarithms of sines, tangents, and secants. [4] [5]
He then diverged from Napier's methods in order to ensure all of the logarithms were positive. [6] A new edition of "New Logarithmes" was published in 1622 and contained an appendix with the natural logarithms of all numbers 1-1000. [7]
Along with William Oughtred and Richard Norwood, Speidell helped push toward the abbreviations of trigonometric functions. [7]
Speidel published a number of work about mathematics, including An Arithmeticall Extraction in 1628. [8] His son, Euclid Speidell, also published mathematics texts. [9]
John Speidell ( fl. 1600–1634) was an English mathematician. He is known for his early work on the calculation of logarithms.
Speidell was a mathematics teacher in London [1] [2] and one of the early followers of the work John Napier had previously done on natural logarithms. [3] In 1619 Speidell published a table entitled "New Logarithmes" in which he calculated the natural logarithms of sines, tangents, and secants. [4] [5]
He then diverged from Napier's methods in order to ensure all of the logarithms were positive. [6] A new edition of "New Logarithmes" was published in 1622 and contained an appendix with the natural logarithms of all numbers 1-1000. [7]
Along with William Oughtred and Richard Norwood, Speidell helped push toward the abbreviations of trigonometric functions. [7]
Speidel published a number of work about mathematics, including An Arithmeticall Extraction in 1628. [8] His son, Euclid Speidell, also published mathematics texts. [9]