Going Dutch: How England Plundered Holland's Glory

by Lisa Jardine

  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 2 January 1663 (old style). He apologised for having ‘forgotten’ to write, blaming this on the fact that he had nothing very positive to tell Huygens about the performance of ‘his’ (that is, Bruce’s) clocks. The sea trials of the two pendulum timekeepers during his journey to London had not been a success. As they left the harbour, the ‘packet-boat’ which Bruce had secured for the crossing was hit by a contrary wind, ‘and the boat was so small that even though it really was not a storm, the ship was shaken more strongly than one can shake a cradle, so that the suspending shaft [vis] that went into the ball and socket [boule] broke under the vibrations of the ship, and the older [clock] fell, while the newer [clock] stopped’.46

  A flurry of letters from Bruce and Sir Robert Moray to Huygens followed, detailing what had happened during the trials, and describing work the two Scots were now carrying out together in London to improve the clocks’ performance against the next trials. On 9/19 January Moray wrote to Huygens from London to tell him that he and Bruce were in discussions about ‘your clocks’, and ‘the design which would make them succeed at sea’. More modifications, then, were being undertaken, this time with the help of the English clockmaker Ahasuerus Fromanteel, whose son John had recently returned from several years’ training in The Hague, learning to manufacture the new pendulum clocks with Huygens’s original clockmaker Salomon Coster.47 The clock which had fallen during the journey was too badly damaged to be repaired, and was replaced by one entirely manufactured in London by Fromanteel.

  ‘I advised [Mr Bruce] to try the clocks two at a time,’ wrote Moray to Huygens, ‘and to adjust them well beforehand on land.’48 This must have irritated Huygens, who had made precisely these preparations before Bruce set sail.49 He replied immediately, assuring Moray that Bruce had already told him exactly what had happened to the clocks, and that he, Huygens, was undeterred and keen to conduct further, longer-distance trials. In a postscript he added that he was about to write to Bruce, as soon as he had finished some further modifications to ‘my clock’.50

  On 16 January 1663 (old style) Bruce wrote to tell Huygens that the damaged clocks were about to arrive (they had been held up at customs): ‘I expect them to morrow and then I shall show them to Sir Robert Moray & lett yow know their [his] opinions of them.’51 Huygens remained optimistic. ‘The lack of success you have had does not bother me,’ he responded, ‘nor does it diminish my good opinion of our undertaking’.52 He told Bruce that he had begun modifying his clock design in consultation with his Dutch clockmaker Severijn Oosterwijk, and would let him know how the improved mechanisms behaved.53

  At the beginning of March 1663, Moray wrote to Huygens letting him know that he and Bruce were going to conduct further trials ‘at sea, going as far as the Dunes, to try out Mr Bruce’s clocks, which he is trying to adjust to the best of his ability’.54 (Note that for Moray, ‘your clocks’ (Huygens’s) have now become ‘Mr Bruce’s clocks’, though essentially the same two timepieces are involved.) The usually conciliatory and tentative Moray continues, somewhat testily:

  You are right in saying that the movement of large boats is gentler than that of small ones, but in heavy swells, particularly when the wind is head on, or when the ship is at anchor, the shocks are stronger and more violent. But what I fear most is not the agitation the ship gives to the whole body of the clock (though I am worried that that may have its effect also) but rather that the sudden movements of the ship downwards, and in the contrary direction, which in the one case will make the pendulum slow down, in the other will accelerate it, sometimes making it heavier, sometimes lighter, and either way unequally, which it seems to me is bound to cause deregulation in the mouvement of the clock’s mechanism. But it still seems worth testing this experimentally.55

  This critical commentary on the whole Bruce–Huygens project suggests that Moray, usually genial and urbane, is drawing on broader Royal Society discussions which had taken place concerning the performance of the clocks. Indeed, I’m afraid this sounds awfully as if it was drafted by Hooke.56

  Sure enough, we learn that Lord Brouncker (President of the Royal Society) and Robert Hooke (Curator of Experiments) had both taken part in those trials ‘at sea, going as far as the Dunes’ on ‘one of his Majesties Pleasure-Boats’.57 And according to Hooke, they ‘experimentally found [the method of suspension] useless to that effect’, though Hooke claimed he could see ways to correct the deficiencies of Bruce’s ball-and-socket suspension arrangement.58 Both Hooke and Brouncker had experience working with precision timekeepers, and both had an interest in perfecting their use to determine longitude at sea.59 Both were now collaborating with Bruce (who, we recall, had impeccable connections on both sides of the Narrow Sea, in London and The Hague) in the hope of achieving a clock-based solution to the longitude problem.60

  So by early 1663, Robert Hooke has joined the team of Dutch, Scottish and English clock experts collaborating in the development of precision longitude timekeepers. As he later insisted, he had been conducting experiments with clock design for several years; now that experience is funnelled into the Bruce–Huygens project.

  As far as Huygens was concerned, Hooke was a background figure in the activities of the Royal Society, an experimentalist and instrument-maker, who was inclined to make exaggerated claims about his technical competence. Both Moray and Brouncker were well-informed amateurs, with a private and a professional interest in precision timekeepers (both owned state-of-the-art clocks and watches themselves, and knew how to look after them).61 For the purposes of the longitude-timekeeper developments and trials, Hooke was their expert technician, acting as adviser and consultant at the English end of design and testing, who fed his results into Moray and Brouncker’s dealings on this topic with the Royal Society (including Bruce and Huygens). Everything Hooke told Moray was directly communicated to Huygens; all Huygens’s comments were relayed back to the Royal Society. The fact that England and Holland were at war for much of this period was apparently irrelevant.62

  This two-way investigative traffic between London and The Hague provides a context for the collection of scattered papers belonging to Hooke which are now in the Wren Library at Trinity College, Cambridge. These are undated, but the first section seems to correspond to a period of ongoing discussions between Hooke, Brouncker and
Moray (with some interventions by Wilkins and Boyle), preparatory to Hooke’s lodging a patent claim for a longitude clock of his own design on behalf of the Royal Society, during the period 1663–65.63 After Hooke’s death, his friend and executor Richard Waller claims to have seen the draft patent document in Moray’s hand among Hooke’s papers.64 We are now in a position to note that Moray was also the person who had drafted a competing patent on behalf of Bruce and Huygens for their longitude timekeepers, which was being negotiated at exactly the same time.

  On 13 January 1664, ten months after Hooke had assisted at the trials of the Bruce–Huygens clocks and pronounced them unsatisfactory, Brouncker reported to the Royal Society that Hooke had ‘discovered’ to himself, Sir Robert Moray and Bishop John Wilkins (Hooke’s mentor, and a founder of the Society) in confidence ‘an invention which might prove very beneficial to England, and to the world’.65 The Society agreed to pay up to £10 for trials. Moray later described it as ‘an invention of his for measuring time at sea better than pendulum clocks can, and indeed as well as they do on land’, and told Huygens that Hooke had been working on it for some time. He had ‘given a proof [preuve] of it to the President, on a watch which I lent him’. However, Moray added that ‘having compared it to his own pendulum clock [the President] found that [Hooke’s] did not keep good time’.66 On 15 September Hooke wrote to his patron Robert Boyle that he hoped ‘shortly to make some observations … with an exact timekeeper, which, I have some reason to believe, shall not be much excelled by any whatever. But these are not yet completed.’

  On 18 January 1665, it was announced at the Royal Society meeting that Hooke was ready to apply for a patent for his longitude timekeeper.67 At the meeting in question doubts had been expressed as to how satisfactorily the Bruce–Huygens clocks had performed during lengthy trials to Guinea and back (I will return to these trials shortly). The Society had backed the Guinea trials heavily, and staked a lot on their success; now Hooke offered them an alternative timekeeper.

  Hooke’s first biographer, Richard Waller, has preserved a fragment of a memoir by Hooke himself, describing what happened next:

  I shew’d a Pocket-watch, accommodated by a Spring, apply’d to the Arbor of the Ballance to regulate the motion thereof; concealing the way I had for finding the Longitude; this was so well approv’d of, that Sir Robert Moray drew me up the form of a Patent, the principal part whereof, viz. the description of the Watch, so regulated, is his own hand Writing, which I have yet by me.68

  Waller goes on to confirm Hooke’s statement on the strength of original documents then in his possession, shortly after Hooke’s death:

  In confirmation of what is abovesaid, I met with a Draught of an Agreement between the Lord Brouncker, Mr. Boyle, and Sir Robert Moray, with Robert Hooke Master of Arts to this purpose, that Robert Hooke should discover to them the whole of his Invention to measure the parts of Time at Sea as exactly and truly as they are at Land by the Pendulum Clocks invented by Monsieur Huygens […] as also of a Warrant to be granted by the King to Robert Hooke, M.A. &c. for a Patent for the sole use of the said Invention for fourteen Years, and sign’d by his Majesty’s Command, William Morrice.69

  This last document surfaced briefly at auction some years ago, only to disappear again to a private buyer.70 It clearly confirms all the key points from Waller’s account: it describes (in Hooke’s hand, inserted into a document largely in Morrice’s) a spring-regulated longitude timekeeper, ‘different from all other watches or clockes by hauing instead of a Ballance a Spring of mettall/wood/quill/bone/glass or other fit matter so aplied to the Arbor of the Ballance that it makes it moue alwise equally’; it is signed by William Morrice in his capacity as Secretary of State, a position he held until September 1668; and it also invokes the names of Sir Geoffrey Palmer ‘Attorney Generall’ and Sir Heneage Finch ‘Solicitor Generall’ (both men left these posts before 1670). It allows us to say with reasonable confidence therefore, though sadly without the evidence before us, that Hooke had indeed come close to applying for such a patent, in direct response to the Bruce–Huygens pendulum-clock-based attempts at a longitude timekeeper, during the first half of 1665.

  There is no doubt that Hooke’s idea of using springs as isochronous regulators in place of pendulums was transmitted to Huygens by both Moray and Oldenburg. On 30 September 1665, for example, the very day on which Moray told Huygens in a letter that Hooke had demonstrated a spring-regulated clock or watch to himself and Lord Brouncker two years earlier, Moray wrote to Oldenburg, in a letter, now lost, that Waller saw:

  You will be the first that knows when his [Huygens’s] Watches will be ready, and I will therefore expect from you an account of them, and if he imparts to you what he does, let me know it; to that purpose you may ask him if he doth not apply a Spring to the Arbor of the Ballance, and that will give occasion to say somewhat to you; if it be that, you may tell him what Hooke has done in that matter, and what he intends more.71

  Hooke’s not-so-confidential negotiations with Brouncker, Moray and Wilkins to obtain a patent on behalf of the Royal Society for Hooke’s longitude timekeeper broke down in mid-1665. The senior officers of the Society were of the opinion that because Hooke insisted on stating that a spring regulator could be applied to a timekeeper in many different ways, no patent would be granted, since to do so would be to inhibit developments other than Hooke’s based on the same principle.

  At precisely the same time that they were dealing ‘in secret’ with Hooke’s proposed revolutionary designs for longitude timekeepers, Brouncker and Moray had taken it upon themselves to move the Bruce–Huygens clock trials onto a more systematic footing, with the Royal Society’s official backing. They arranged for Robert Holmes, captain of the Jersey, to carry the two pendulum clocks to and from Lisbon in 1663, and then on a longer voyage to Guinea and back in 1663–64.72

  For the history of development of longitude timekeepers these trials were a turning point. By contrast with Bruce’s trials, those conducted during Holmes’s voyages, particularly on the voyage to Guinea, were spectacularly successful. The clocks ran well throughout the journey, Holmes set them regularly and kept them running, and crucially, the clocks allowed Holmes to make a calculation of his position at a key moment in the Guinea voyage which revealed the inadequacy of traditional longitude-finding methods.

  On the return journey, Holmes had been obliged to sail several hundred nautical miles westwards in order to pick up a favourable wind. Having done so, the Jersey and the three ships accompanying her sailed several hundred more miles north-eastwards, at which point the four captains found that water was running worryingly low on board. Holmes’s three fellow captains produced three conflicting calculations of their current position based on traditional dead-reckoning, but all agreed that they were dangerously far from any potential source of water. Not so, declared Holmes. According to his calculations – based on the pendulum clocks – they were a mere ninety miles west of Fuego, one of the Cape Verde islands. He persuaded the party to set their course due east, and the very next day, around noon, they indeed made landfall on Fuego, exactly as predicted.73 Huygens’s clocks had saved the day.

  This was exactly the kind of publicity the pendulum timekeepers needed in order to capture the public imagination. Moray’s report of this dramatic success, in a letter to Huygens dated 23 January 1665, is clear as to its impact: ‘At last Captain Holmes has returned, and the account he has given us of the experiment with the pendulum clocks leaves us in absolutely no doubt as to their success.’74

  The following day Huygens replied. He was delighted to hear of Holmes’s triumph with the clocks; every line of the account gave him the greatest pleasure, and he thanked Moray for being the bearer of such good tidings.75 Holmes’s report was published verbatim in the Royal Society’s Philosophical Transactions and in French in the Journal des sçavans, and eventually featured as the unique account of a sea trial of pendulum clocks to be included in Huygens’s landmark book the Horologi
um Oscillatorium, published in 1673.76 Right down to the present day, the spectacular success of these trials is invoked as the crucial evidence on the basis of which Huygens’s pendulum-clock timekeepers take their place as a significant step in the progression from the theoretical aspiration to determine longitude at sea using a precision clock, to the realisation of that dream with John Harrison’s longitude timekeeper in the following century.

  The success of the Holmes trials probably led directly to Moray and Brouncker abandoning attempts to agree a patent document with Hooke. By this time too, ironically, Moray had given up hope of getting Bruce and Huygens to agree a fair distribution of financial reward, and abandoned their patent bid also.77

  So it might appear that there is some justice in the fact that Huygens has continued to receive most of the credit for early longitude clock trials, and developments culminating in the balance-spring-regulated pocket watch, ever since. But my own research has recently uncovered evidence to suggest that Hooke deserves more credit, and Huygens perhaps a little less.

  The problem with the story I have just recounted is that Sir Robert Holmes (as he later became) was not known as a person who could be relied upon. He is, in fact, infamous as the hot-tempered, violent and uncontrollable commander of the English fleet whose impetuous exploits were responsible for starting both the second and the third Anglo–Dutch wars. He had served under Prince Rupert and James, Duke of York, and eventually rose to the rank of Admiral. In 1664, on the very voyage on which he was supposed to be testing the Bruce–Huygens clocks, he sacked the Dutch trading stations along the coast of Guinea one by one, seizing goods and property and laying waste the settlements.78 On his return he was twice imprisoned in the Tower of London (on 9 January and 14 February 1665), either for having gone beyond orders or for failing to bring back adequate amounts of booty, it is not quite clear which. His actions led directly to the Dutch declaring war on 22 February 1665, by announcing that they would retaliate against any British shipping in the Guinea region, at which point Holmes was released and pardoned, in order to command his Majesty’s forces. In August 1666 he attacked and destroyed by fire 150 East Indiamen in the Vlie estuary and sacked the town of Westerschelling on adjacent Terschelling island.