Christiaan Huygens – A family affair - Proeven van Vroeger

clocks. 357 Generally, the role of Constantijn Sr. was more of commanding specific mailings or
commenting on possible improvements or mistakes. 358
More than one of Christiaan’s brothers was also involved in the development and
building of the air pump. In order to realize the coming about and constant functioning of this
extremely expensive instrument, Christiaan had arranged that his brother Constantijn and
brother-in-law Philips Doublet would give him financial support. However, faced with several
initial set-backs “due to an unevenly bored cylinder and a recalcitrant workman” and extra
costs, both young men eventually pulled back from the project, surrendering Christiaan
completely to his own stipend he received from his father 359 – or perhaps his father paid him
extra for the machine’s maintenance. Furthermore, his brother Lodewijk – at the time in Paris
– was chartered by his brother to convince Jacques Rohault “to construct a pump, and to test
it by producing anomalous suspension, of which Huygens enclosed a diagram;” a project at
distance that failed for reason of Christiaan Jr.’s absence. 360 Throughout 1661 – 1663 the air
pump was a subject of intensive discussion between Lodewijk and his brother.
The “business” of instrument invention was serious enough for father Huygens to
invest some extra time in it – round about the time that he was sent out for the negotiations to
357 Ibid., Vol. IV, 1166 – Christiaan to Constantijn Jr. (Nov. 16, 1663): “Chez le Sieur Pascal il y a 2
horologes a pendule que Monsieur Chieze a fait faire pour la Signora Anna et un autre Italien de nos
amis. Ils sont desia achevez et le frere Louis s’estoit chargè d’avoir soin de les envoier. Mais estant
absent je voudrois bien que vous les addressassiez a L’unicus, et par luy a Mademoiselle vander Elst, qui
les envoyera a Paris par les Rouliers”. Vol. IV, No. 1175 – Christiaan to Constantijn Jr. (Nov 30, 1663):
“Talks about horloges for Milord Brouncker (80 livres) – 110. 2 pendules for Pascal. Other has to be
given to Don Diego. “Cela vous sera tout aussi facile ou au frere Louis que de les adresser a Rotterdam,
et nos amis ont grande impatience de les tenir, en seront trois fois plustost servis. Il Signor Padre le
desire aussi ainsi et m’a commandè de vous l’escrire.” Vol. IV, No. 1177 – Constantijn Jr. to Christiaan
(Dec 6, 1663): “Les deux pendules seront envoyées selon que vous desirez la sepmaine prochaine par
Anuers auec les plumes et les cordes que mande mon Pere.” “Les rapports du pendule me rejouissent
fort et Seuryn aussi. Il dit qu’il croid auoir trouvé quelque chose pour les suspendre encore mieux que
ces autres ne l’ont esté.” Vol. IV, No. 1178 (Dec. 1663) Christiaan Jr.: “J’ay escrit a mon frere qui est a
la Haye qu’il fist le marchè avec l’horologer pour la monstre de Milord Brounker au plus juste prix qui
est a ce qu’il me mande de 110 livres monnoye d’Hollande.”
358 Ibid., Vol. VI, No. 1576 – Christiaan to Lodewijk (Feb. 11, 1667): “Mon Pere m’escrit par vostre
suggestion ou celle du frere de Zeelhem touchant le payement de Severyn l’horologer de la pendule que
je luy ay fait faire pour Monsieur Morray. Il y a un peu de ma faute, je l’avoue, de ce que je n’ay pas
insistè assez pour ledit paiement.mais j’auray soin qu’il n’y perde rien et vous pouvez luy dire que je luy
seray avoir son argent ou que je luy paieray moy mesme.”
359 SHAPIN, S. & SCHAFFER, S. (1985) Leviathan and the air-pump : Hobbes, Boyle, and the experimental
life : including a translation of Thomas Hobbes, Dialogus physicus de natura aeris by Simon Schaffer, Princeton,
N.J., Princeton University Press., p237, STROUP, A. (1981) Christiaan Huygens & the Development
of the Air Pump. Janus: Revue Internationale de l'Histoire des Sciences, de la Médecine et de la Technique, 68, 129-
58., p130
360 SHAPIN, S. & SCHAFFER, S. (1985) Leviathan and the air-pump : Hobbes, Boyle, and the experimental
life : including a translation of Thomas Hobbes, Dialogus physicus de natura aeris by Simon Schaffer, Princeton,
N.J., Princeton University Press., p244, 265
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