Wilhelmus de Nulandt (o Nuland, o Nylandt). Di lui si sa molto poco. Visse a L’Aia, dove s’interessò di ottica, e dove conobbe Constantijn Huygens, che così ne scrive al figlio Christiaan (si cita la trad. inglese che compare in Fokko Jan Dijksterhuis, Lenses and Waves: Christiaan Huygens and the Mathematical Science of Optics in the Seventeenth Century, Springer, Heidelberg 2004, p. 79): «The worthy Baron de Nulandt begins to talk like a great savant, and lets me cooly know that he has found the same proportions of glass to imitate the hyperbola of which I have talked to him in my letter, although I’m sure that this is infinitely beyond his capacities. The calculations he sends me are far from the truth, and I will not refrain from showing him this». Così lo descrive M.J. Petry nell’Appendice a Spinoza’s Algebraic Calculation of the Rainbow & Calculation of of Chance, Springer, Heidelberg 1985 (p. 105): «the eccentric soldier of fortune Baron von Nulandt, an acquaitance of Huygens and Tschirnhaus and probably also of Spinoza».