Visited by Karl von Hessen-Kassel and Willem Meester

Date: 
October 1, 1685

In October 1685, shortly before Constantijn Huygens Jr. wrote to his brother Christiaan about it, Karl von Hessen-Kessel visited Leeuwenhoek at his home laboratory. Hessen-Kessel was accompanied by Willem Meester, a Dutch army engineer and explosives expert who had worked with Christiaan for many years.

Document: 

Letter from Constantijn Huygens to his brother Christiaan, November 5, 1685, no. 2408 in Huygens' Ouvres Completes.

Il avoit esté avec luy chez Leeuwenhoeck qui ne luy avoit voulu montrer de ses microscopes que ceux qu'il montre a tout le monde et dont les petits verres avoyent pour le moins la largeur d'un dos de coûteau de foyer, que quand le Landgrave luy avoit demandé s'il en pourroit avoir quelques uns de sa façon, il avoit repondu avec beaucoup de fierté qu'il n'en avoit jamais donné a personne, ny avoit dessein de le faire, que si une fois il se laisseroit aller à cela il seroit en suitte esclave de tout le monde, et d'autres choses de cette force là. Apres avoir montré trois ou quatre de ses microscopes il les emportoit, et en alloit querir autant d'autres, disant qu'il faisoit cela de peur qu'il ne s'en egarast quelqu'un entre les mains des spectateurs, qu'il ne se fioit pas aux gens, particulierement aux Allemans; repetant cela deux ou trois fois. O che bestia!

He (Meester) had gone with him (Karl, Landgraaf van Hessen-Kassel) to Leeuwenhoeck’s, who had wanted to show him only those of his microscopes that he showed to everyone, which little glasses had at least a focal distance equal to the back of a household knife. When the Landgrave asked whether he could have some that he had made, he replied with great pride that he never gave any to anybody, nor intended to do so, and that if once he were ever to submit to that, he would soon be enslaved to everyone, and other things of that nature. After showing three or four of his microscopes, he carried them off, and went to fetch as many others, saying that he did this for fear that any of them might get mislaid in the hands of the spectators, that he did not trust people, especially Germans, repeating this two or three times. Oh, what a brute!

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