Abstract
In this article, the life and work of a hitherto unknown Amsterdam scientific instrument maker is discussed. In the years 1659–1660 this man, the horologist Stephanus Keus, claimed to have invented a lamp that could produce a very intense light. Several members of the well-known Hartlib Circle were intrigued by this invention. With this ‘Great Light’ one should be able to illuminate huge spaces. In London, Samuel Hartlib wondered whether this device could be used to test an old theory – formulated in 1594 by Sir Hugh Plat – that the intensity of light might be magically enhanced by the use of lenses. So, Hartlib ordered such a ‘Great Light’ in Amsterdam, as well as some other optical equipment made by Keus, as this man also produced telescopes and microscopes. Keus was also well connected to the educator and theologian Jan Amos Comenius, who witnessed several tests of Keus’s ‘Great Light’. In an anonymously published tract, Comenius used an air rifle made by Keus to disprove René Descartes’s theory about the incompressibility of his supposed matter particles. The fact that the air in Keus’s gun could be compressed up to twenty times its normal density demonstrated, according to Comenius, that Descartes’s statement must be incorrect. For Keus, these moments of fame were very short-lived. In 1660, the restoration of the English monarchy saturated public attention to such a degree that no English scholar ever investigated Keus’s products.
| Translated title of the contribution | The Amsterdam instrument maker Stephanus Pietersz Keus (c.1605–1679) and his contacts with the ‘Hartlib Circle’. |
|---|---|
| Original language | Dutch |
| Pages (from-to) | 110-122 |
| Number of pages | 13 |
| Journal | Studium. Tijdschrift voor Wetenschaps- en Universiteitsgeschiedenis |
| Volume | 12 |
| Issue number | 1-3 |
| Publication status | Published - 10 Dec 2019 |
Keywords
- Hartlib Circle
- 17th century
- Scientific Instrument maker
- Jan Amos Comenius
- Optical instruments