Going Dutch_ How England Plundered Holland's Glory - Lisa Jardine [122]
In October 1662, Bruce arrived in The Hague on one of his regular round trips to and from his home in Culross, having used the journey in both directions to test pendulum clocks modified to his own design for their suitability as longitude timekeepers.40 According to Bruce, it was the success of these first trials which convinced Huygens that it was worth pursuing the possibility of adapting his new clocks to determine longitude at sea. He reminded Huygens later:
At my first arivall at the Hage, after the tryall I had made betwixt Scotland & [The Hague] of my watch, when you did me the favour to see me at my chamber, we fell upon the subject of the going of the pendule watches at sea; & you told me positively then that it was your opinione that it was impossible, that you hade been making experiments of it, and all the effects of them was, to be settled in that opinion by them: you did lykewise urge reasons of the impossibility of it.41
It is not clear whether Bruce’s marine clock had been built for him in Holland or England, by Dutch or English technicians, but it was certainly pendulum-regulated.42 He later told Huygens that this clock of his was the same one he had had in his possession in London eighteen months earlier when he and Huygens met there, and that it differed significantly from Huygens’s:
I came afterwards to see that watch by which you hade made your experiment; & I believe you will acknowledge that it was so farre different from mine in the whole way of it that it is not lyke they should ever have met. And the rather I thinke this, that I showed you at London 18 moneths before that tyme the same watch which receaved very small amendments thereafter; & if you hade thought that way able to bring it to passe, you might from that view have ordered one to be made for your tryell.43
Encouraged by their mutual interest and complementary expertise, Bruce and Huygens now began working collaboratively at The Hague, adapting pendulum clocks for sea travel. Bruce favoured clocks with short pendulums for portability; it was he who added a ‘double crutch’ to keep the pendulum swinging in a single plane, and designed the methods of support and suspension which it was hoped would protect the clocks from the most violent of motions arising from storms and high seas – Huygens had simply tried suspending them from ropes.44
It was the wealthy Bruce who paid for two state-of-the-art pendulum clocks, made by Huygens’s current preferred Dutch clockmaker, Severijn Oosterwyck, which they agreed Bruce would test on his next journey to Britain, this time to London. By December the clocks were almost ready, and the two men were spending a lot of time together. On 4/14 December 1662, Christiaan told his brother Lodewijk that he had been slow responding to a letter ‘because of several visits I have received, and principally by that of Mr Brus [Bruce], who did not leave me alone for a single moment all afternoon. And he has been doing that quite often, ever since we set about perfecting our invention for [measuring] Longitudes.’45
In other words, the earliest trials of pendulum-regulated longitude timekeepers – much discussed by historians of science – began as a robustly Anglo–Dutch venture. And once Bruce arrived in London, the correspondence with Huygens that followed demonstrates an extraordinary level of continuing Anglo–Dutch collaboration, with the English contributors now making the running.
For two weeks Huygens waited anxiously for news from London. He consulted the van Aerssens, but even they had not yet heard from their son-in-law. Eventually he received a letter from Bruce, written on