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Ceulen, Ludolph van

1. Dates
Born: Hildesheim, Germany, 28 Jan. 1540
Died: Leiden, 31 December 1610
Dateinfo: Dates Certain
Lifespan: 70
2. Father
Occupation: A Merchant
Bosmans says that his father was in very modest condition, so that Van Ceulen's education stopped with elementary. I interpret this as poor.
3. Nationality
Birth: German
Career: Dutch
Death: Dutch
4. Education
Schooling: No University
No evidence of any university education. 5 Religion: Cal.
Nothing whatever is said; he must have conformed to the Calvinist church of the Netherlands.
5. Religion
6. Scientific Disciplines
Primary: Mathematics
Van Ceulen computed pi to 20 decimal places, and later, using Archimedes method (to which he added devices to speed things up) to 33 and ultimately to 35 places. In this he made himself an expert in trigonometry.
7. Means of Support
Primary: Schoolmaster, Academic
1580: in Delft he was a fencing master and a teacher of mathematics.
1594: he received permission to open a fencing school in Leiden.
1600-10: he was appointed a teacher of arithmetic, surveying, and fortification in the engineering school that Maurice established in Leiden (with a salary of f400, later raised somewhat). Willibrord Snel was his student, and Snel later translated at least two of his works into Latin.
8. Patronage
Types: Scientist, Magistrates
Van Ceulen formed friendships with powerful figures in the intellectual and scientific community of the Netherlands, including Jan Cornets de Groot, Stevin, and Adrien Van Roomen. They clearly helped his career.
He dedicated his book, On the Circle, to the Magistrates of Leiden.
9. Technological Involvement
Types: Military Engineering, Cartography
Although he had that appointment in the engineering school, nothing whatever is said about the exercise of such functions. Nevertheless this seems entirely analogous to writing books on the subjects.
10. Scientific Societies
Memberships: None
Informal connections: he was friendly with Jan de Groot, Snel, and Stevin. De Groot translated Archimedes into Dutch expressly so that van Ceulen could read it.
In the late 80's there was a lively exchange of pamphlets in the Netherlands on the value of pi--which involved, in addition to van Ceulen, Simon van der Eycke, Coignet, Stevin, and others. Soon after that there was another on the calculation of interest. I do not recall an earlier example of this sort of a nascent scientific community.
  1. Nieuw nederlandsche biografische woordenboek.
  2. H. Bosmans, "Ludolphe van Ceulen," Mathésis. Recueil mathematique à l'usage des écoles speciales (Ghent), 39 (1925), 352-60.
Not Available and Not Consulted
  1. David Bierens de Haan, Bouwstoffen voor de geschiedenis der wis- en natuurkundige wetenschappen in der Nederlanden, (Amsterdam, 1876-8), nos. 8, 9, 17. (Reprinted from Verslagen en mededeelingen der Koninklijke Akademie van Wetenschappen Amsterdam.) H. Bosmans, "Un émule de Viète," Annales de la Société Scientifique de Bruxelles, 34, pt. 2 (1919), 88-139.
Compiled by:
Richard S. Westfall
Department of History and Philosophy of Science
Indiana University

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©1995 Al Van Helden
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