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Delamain [Delamaine], Richard

1. Dates
Born: unknown first recorded in 1629.
Died: before 1645 when his widow petitioned.
Dateinfo: Flourished (two dates give known period)
Lifespan: N/A
2. Father
Occupation: Unknown
No information.
No information on financial status.
3. Nationality
Birth: English
Career: English
Death: English
4. Education
Schooling: No University
Originally a joiner by trade, he studied mathematics at Gresham College.
5. Religion
Affiliation: Anglican assumed
6. Scientific Disciplines
Primary: Mathematics
Delamain is known almost entirely for his essay, Grammelogia, or the Mathematical Ring, which deals with practical mathematics and a couple of instruments, and for the controversy the work generated with Oughtred. He also published The Making, Description, and Use of . . . a Horizontal Quadrant, 1631, which was part of the controversy. As far as Oughtred was concerned, Delamain was a simple plagiarist who stole instruments that Oughtred designed but did not seriously understand them. On the whole modern commentators appear to doubt Delamain's originality. There is enough uncertainty for me to leave him in the catalogue.
7. Means of Support
Primary: Art, Schoolmastering, Patronage
Secondary: Government
Originally he was a joiner. After studying in Gresham College, he supported himself by teaching practical mathematics in London. Later he became mathematical tutor to King Charles I, and (according to his widow) Quartermaster-general. We know from governmental records that he was employed by the Master of Ordnance in measuring forts and castles.
8. Patronage
Type: Court
Delamain sent the manuscript of his Grammelogia to King Charles in 1629, and Charles retained his service as tutor at a salary of 40 per annum. Delamain dedicated the published pamphlet to Charles. A few years later he petitioned for an engineer's post. Following an interview with the King at Greenwich in 1637, he was granted a warrant for making a number of mathematical instruments. He fashioned a number of instruments for the King.
9. Technological Involvement
Types: Instruments, Applied Mathematics, Cartography
He constructed a number of mathematical instruments, including a large silver sundial. Two instruments were central to the quarrel with Oughtred and the charge of plagiarism--the circular slide rule and the horizontal instrument (a sundial with other uses as well).
His mathematics was wholly practical, and the circular slide rule was a calculating device.
See above for his work as a surveyor.
10. Scientific Societies
Memberships: None
Relationship with Oughtred. He was a pupil of Oughtred, and in the early days of their association the two men became close friends. Later, they quarreled violently over priority in invention of the circular slide rule and the horizontal quadrant.
  1. Dictionary of National Biography (repr., London: Oxford University Press, 1949-50), 5, 751. E.G.R., Taylor, The Mathematical Practioners of Tudor and Stuart England, (Cambridge, 1954), p.201. QA27 .G7T23 Florian Cajori, William Oughtred, (London-Chicago, 1916). QA29 .O8C2 A.J. Turner, "William Oughtred, Richard Delamain and the Horizontal Instrument in 17th-Century England," Annali dell'Istituto e Museo di Storia della Scienza di Firenze, 6.2 (1981), 99-125.
Not Available and Not Consulted
  1. A.J. Turner, "The Mathematical Practitioner Richard Delamain and his Son Richard Delamain the Younger, Mathematician and Radical Preacher." Turner announced the preparation of this article in his article of 1981; I do not know whether it ever came to fruition.
Compiled by:
Richard S. Westfall
Department of History and Philosophy of Science
Indiana University

Note: the creators of the Galileo Project and this catalogue cannot answer email on geneological questions.

1995 Al Van Helden
Last updated
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