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Hartsoeker, Nicolaas

1. Dates
Born: Gouda, 26 March 1656
Died: Utrecht, 10 Dec. 1725
Dateinfo: Dates Certain
Lifespan: 69
2. Father
Occupation: Cleric
Christiaan Hartsoeker, a Remonstrant minister.
No information on financial status.
3. Nationality
Birth: Dutch
Career: Dutch, French, German
Death: Dutch
4. Education
Schooling: Leiden
Although some dissent, most of the few authorities say that he studied for a time at Leiden. No one suggests a degree.
5. Religion
Affiliation: Calvinist, Catholic
His father was a remonstrant minister.
In France he converted to Catholicism.
6. Scientific Disciplines
Primary: Instrumentation, Optics, Natural Philosophy
Subordinate: Physics, Embryology
He published Essai de dioptrique in 1694 plus a number of papers. The Essai also contains the exposition of a general natural philosophy.
He published a number of books on physics, which contain more on the philosophy of nature than on physics.
His observations in embryology culminated in the homunculus.
7. Means of Support
Primary: Instruments, Patronage
Secondary: Academia, Government
In 1679 he set up as an instrument maker and wine merchant. The venture was unsuccessful, but he continued with instruments the rest of his life. In France, from 1684-96, he was an instrument maker, primarily optical instruments. He inspected the royal glass works in Cherbourg, and he was commissioned to make lenses and instruments for the Jesuits in the Orient. It has recently been revealed that he was an agent of the French government in 1692, supplying it with information about the Netherlands in its war against the Netherlands.
When he returned to the Netherlands in 1696, he gave instruction to Peter the Great in physics and refused an offer of a chair in physics in St.Petersburg.
In Amsterdam he taught physics to the Landgrave of Hesse- Kassel (the lessons were published as Conjectures physiques and Suite de conjectures physiques). He also won the favor of the Elector Palatine, whose court mathematician Hartsoeker became in 1704. He lived in Dusseldorf from 1704-16, and was at the same time Honorary Prof. of Philosophy at the Univ. of Heidelberg (the Landgrave). After the Elector Johan Willem died in 1716, Hartsoeker returned to the Netherlands.
8. Patronage
Types: Scientist, Court Official, City Magistrate
Hartsoeker went to Paris in 1678 with Christiaan Huygens, who introduced him to scientific circles there. Hartsoeker's naiveté in regard to the politics of the scientific circle led to a break with Huygens.
Later, in the 1684-96 period, Hartsoeker gained the support of Cassini who liked the quality of his lenses.
The patronage of two German courts is manifest in the details above. It is of interest that after the death of the Elector, the Landgrave of Hesse-Kassel tried to attract Hartsoeker to his court, but Hartsoeker, tired of court life, declined and returned to the Netherlands.
Niceron says that the magistrates of Amsterdam recommended Hartsoeker to Peter the Great, and that to defray Hartsoeker's expenses in that foray they established a small observatory for him. Others say that the observatory was set up for Peter and that the magistrates let Hartsoeker use it after Peter departed.
9. Technological Involvement
Type: Instrumentation
Hartsoeker was always interested in optical instruments. He claimed to have developed a method of making small glass globules for microscopes, though his priority in this is doubted. He definitely made lenses of different focal lengths, some of which survive; one lens is said to have had a focal length of 600 feet. He made a number of instruments, not just optical instruments, for the Paris observatory. He constructed a burning glass of great size.
10. Scientific Societies
Memberships: Académie Royal des Sciences, Berlin Academy
In 1699 a foreign member of the Academy Royale.
Later a member of the Berlin Academy.
  1. Considering the considerable prominence of Hartsoeker, there is a surprising paucity of biographical information about him.
  2. J.P. Niceron, Memoires pour servir a l'histoire des hommes illustres (1700s), 8.
  3. Nieuw Nederlandsch Biographisch Woordenboek.
  4. M. Daumas, Les instruments scientifiques, (Paris, 1953).
  5. Levensbeschryving van eenige voorname meest nederlandsche mannen en vrouwen, 3rd ed., 10 vols., (Haarlem, 1794), 2, 167-86.
  6. Alice Stroup, "Science, politique et conscience aux débuts de l'Académie Royale de Sciences, Revue de synthèse, 4th series, Nos. 3-4 (July-Dec. 1993, 423-53.
Not Available and Not Consulted
  1. Christiane Berkvens-Stevelinck, "Nicolas Hoartsoeker contre Isaac Newton ou pouquoi les planètes se meuvent-elles?" Lias, 2 (1975), 313-28. Stroup says that this is the best recent summary of Hartsoeker's life.
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
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