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  Having found and named Botany Bay, where Banks and the other “scientific gentlemen” were delighted by the discovery of hundreds of new plant and animal species, Cook sailed north into the dangerous waters that lie between the Great Barrier Reef and the mainland. No European ship had been there before, and the Endeavour was alone: she had no consort on which to rely in case of difficulty. This was a mistake that Cook would not repeat on his two subsequent voyages.

  On the night of June 10–11, 1770, when the ship was just north of Cape Tribulation (aptly named by Cook himself “because here begun all our troubles”) in what is now Queensland, Cook cautiously shortened sail and stood out from the mainland. His aim was to avoid dangers visible ahead and to confirm whether there were any islands in the offing, but he was as yet unaware of the existence of the Great Barrier Reef, which now hemmed him in ever more tightly. There was a good sailing breeze and it was a “clear moonlight night”; soundings were taken continuously with the lead-line. The water began to shoal, and the crew were anxiously standing by to drop anchor when it suddenly became deeper again. Cook decided he could risk carrying on, but just before 11 P.M., moments after a sounding had shown they were in 17 fathoms (102 feet), “and before the Man at the lead could heave another cast the Ship Struck and stuck fast.”17

  The Endeavour had grounded on an isolated coral reef at the top of the tide—the worst possible moment, as it meant the sea level would soon be falling—and she was badly holed. It was an extremely perilous position, so desperate in fact that Cook ordered the guns, ballast, stores, and even freshwater to be thrown overboard to lighten the ship. The crew carried anchors out in the boats and tried to haul her off, but she could not be moved. Luckily the wind was light, so the Endeavour was not pounded to destruction, as she well might have been, and after twenty-three hours of exhausting work they at last succeeded in getting her afloat again at the top of the next high tide but one. However, the damage to the hull was so extensive that it was far from clear they would be able to reach the shore (about twenty miles away). By “fothering” the ship—passing a sail coated with a mixture of wool, rope yarn, and dung underneath the damaged part—they managed to get the massive leak under control, and eventually on June 16 succeeded in beaching the Endeavour in a river mouth on the mainland. Cook had chosen his ship well: as a collier, she was designed to take the ground for the discharge of her cargo without suffering damage.* A sizable chunk of coral was found jammed in the hull; if it had been dislodged while they were still at sea the ship would almost certainly have been lost. Banks was deeply impressed by the “cool and steady conduct” of the officers, “who during the whole time never gave an order which did not show them to be perfectly composed and unmov’d by the circumstances however dreadful.”18

  While the ship was being repaired, Cook and Green (the professional astronomer who accompanied him) managed on June 29 to obtain a very accurate longitude by observing the first moon of Jupiter: 214°42'30'' West (or 145°17'30'' East).19 Having set sail again on August 4 it proved extremely difficult to find a safe passage through the “labyrinth” of reefs that extended far beyond the river mouth. When at last they reached the open sea, Cook—though sorry to lose the chance to survey the mainland shore—was relieved at being outside the shoals in which he had been “intangled” since the end of May:

  in which time we have saild 360 Leagues without ever having a Man out of the cheans* heaving the Lead when the ship was under way, a circumstance I dare say never happen’d to any ship before and yet here it was absolutely necessary.20

  But Cook and his crew were far from safe. On August 16, while sailing northward just outside the Great Barrier Reef, the Endeavour was becalmed during the night in a heavy swell that began to drive her slowly but irresistibly toward it:

  A little after 4 oClock the roaring of the Surf was plainly heard, and at day break the vast foaming breakers were too plainly to be seen not a Mile from us, towards which we found the Ship was carried by the waves surprisingly fast. We had at this time not an air of wind, and the depth of water was unfathomable so that there was not a possibility of Anchoring. . . . The same Sea that washed the side of the Ship rose in a breaker prodigiously high the very next time it did rise, so that between us and destruction was only a dismal Valley the breadth of one wave, and even now no ground could be felt with 120 fathoms.21

  They were at least thirty miles from the nearest land, and there were not enough boats to carry the whole crew, yet in this “Truly Terrible Situation not one man ceased to do his utmost, and that with as much Calmness as if no danger had been near.”

  All the dangers we had escaped were little in comparison of being thrown upon this Reef where the Ship must be dashed to peices in a Moment. A Reef such as is here spoke of is scarcely known in Europe, it is a wall of Coral Rock rising all most perpendicular out of the unfathomable Ocean . . . the large waves of the vast Ocean meeting with so sudden a resistance make a most terrible surf breaking mountains high especially as in our case, when the general trade wind* blowes directly upon it.22

  According to Banks, the situation was so desperate that “a speedy death was all we had to hope for.”23 At this critical moment, however, a breath of wind, so small that it would have passed unnoticed in normal circumstances, enabled them to edge away from the reef—with additional help from the oarsmen sweating in the ship’s boats. Soon, however, the “Friendly breeze” failed them and they were once again in danger.

  A small opening was now seen in the Reef about a quarter of a Mile from us which I sent one of the Mates to examine, its breadth was not more than the length of the Ship but within was smooth water, into this place it was resolv’d to push her if possible, haveing no other probable Views to save her, for we were still in the very jaws of distruction, and it was a doubt whether or no we could reach this opening, however we soon got off it when to our surprise we found the Tide of Ebb gushing out like a Mill Stream so that it was impossible to get in; we however took all the advantage possible of it, and it carried us out about a ¼ of a Mile from the breakers.24

  By noon they were a mile or two off the reef but were certainly not out of danger. Cook therefore sent Lieutenant Hicks in a small boat to explore another opening in the reef that they could see a mile or so to the west.

  At 2 oClock Mr Hicks returnd with a favourable account of the opening, it was immediately resolved to try to secure the Ship in it, narrow and dangerous as it was it seem’d to be the only means we had of saving her as well as our selves. A light breeze soon after sprung up at ENE which with the help of our boats and a flood tide we soon enter’d the opening and was hurried through in a short time by a rappid tide like a Mill race which kept us from driving against either side, though the C[h]annell was not more than a quarter of a Mile broad, we had however two boats a head to direct us through. . . .25

  The Endeavour was now out of danger, and Cook—in an uncharacteristic departure from his normal tight-lipped stoicism—took the opportunity to comment on the extraordinary stresses that accompanied the work in which he was engaged. Coming from perhaps the most revered navigator in the history of exploration, the anxieties—and the note even of bitterness—that emerge from this powerful testimony are particularly telling:

  It is but a few days ago that I rejoiced at having got without the Reef; but that joy was nothing when Compared to what I now felt at being safe at an Anchor within it. Such are the Visissitudes attending this kind of Service, and must always attend an unknown Navigation where one steers wholy in the dark without any manner of Guide whatever. Was it not from the pleasure which Naturly results to a man from his being the first discoverer, even was it nothing more than Land or Shoals, this kind of Service would be insupportable, especially in far distant parts like this, Short of Provisions and almost every other necessary. People will hardly admit of an excuse for a Man leaving a Coast unexplored he has once discovered. If dangers are his excuse, he is then charged with Timerousness and want of Perseverance, and at
once pronounced to be the most unfit man in the world to be employ’d as a discoverer; if, on the other hand, he boldly encounters all the dangers and Obstacles he meets with, and is unfortunate enough not to succeed, he is then Charged with Temerity, and, perhaps, want of Conduct.26

  Cook plainly did not expect to incur these criticisms, but he acknowledged that he had perhaps been less than prudent in penetrating so deeply among the islands and shoals on this stretch of coast “with a single Ship, and every other thing considered.” On the other hand, if he had not taken these risks he would have fallen short of his own high standards:

  . . . I should not have been able to give any better account of the one half of it than if I had never seen it; at best, I should not have been able to say wether it was Mainland or Islands; and as to its produce, that we should have been totally ignorant of as being inseparable with the other; and in this case it would have been far more satisfaction to me never to have discover’d it, but it is time I should have done with this Subject wch at best is but disagreeable & which I was lead into on reflecting on our late Danger.27

  Cook does not mention—perhaps he did not even notice—that in the middle of this crisis Charles Green, the professional astronomer who accompanied him, was hard at work making lunar observations to help fix their position. Green’s personal log records in neat copperplate script:

  These obs[ervations] were very good, the Limbs of sun and moon very distinct, and a good Horizon. We were about 100 Yards from the Reef, where we expected the Ship to strike every minute, it being Calm & no soundings, and the swell heaving us right on.28

  Green was not a sailor by training (though as Maskelyne’s assistant he had sailed with him to Barbados for the trials of H4 and held the naval rank of purser), but he was a cool, determined hand, and Cook described him as an “indefatigable” observer. In fact he seems to have taught Cook how to make lunar-distance observations while on the outward passage from England.29 That anyone would attend to lunars at such a time is a clear demonstration of their vital importance, and of Green’s devotion to duty. His log reveals that he was responsible for the majority of the lunar observations made on the voyage, though Cook’s name quite often appears, too. It was a heavy responsibility, and the “young gentlemen” frequently maddened him by failing to provide the assistance he expected. Like a disappointed teacher, Green plainly found it difficult to understand why they did not share his enthusiasm for the higher flights of celestial navigation (Green’s own emphasis):

  22 September 1768— . . . might have made more and better [observations], if Proper Assistance could have been had from the young Gentlemen on board, with pleasure to themselves . . .30

  24 February 1769—[The sea] broke over the Quarter Deck several times while we were observing. . . . The Moon’s altitude I took myself . . . because I could get no one to assist in taking it for me.31

  Green was never to return home. After picking his way through the hazardous and hitherto uncharted Torres Straits, Cook was obliged to call at the appallingly unhealthy Dutch settlement of Batavia (modern Jakarta) to make essential repairs to the ship. Malarial fever and dysentery ran through the Endeavour’s crew, and Green was among the many victims, dying at sea shortly after they set sail for home in January 1771. By the time they reached Cape Town the death toll had reached thirty-four, and five more were to succumb before they reached home—more than a third of the ship’s original complement.32 They had survived shipwreck on the Great Barrier Reef and had reached Batavia in remarkably good health, so it was a cruel irony that this detour to an outpost of European civilization should have cost so many lives.

  LUNARS WERE ALL the more vital on Cook’s first voyage because he was not equipped with a timekeeper, though by that time—as both he and Green would have known—H4 had proven its worth. They did, however, have the benefit of the new Nautical Almanac, though its predictions expired before the long voyage was over. (With such extended voyages in mind, Maskelyne was to ensure that future editions of the Almanac were produced at least four or five years in advance.)

  When Cook set sail again in 1772 aboard the Resolution, this time accompanied for safety by the Adventure, four timekeepers were carried, though only one of them performed reliably enough to be of outstanding navigational value. This device was a copy of Harrison’s H4, specially commissioned by the Admiralty from Larcum Kendall, which was now known as “K1.” Cook had high praise for K1, which he described as “our trusty friend the Watch,”33 but he certainly did not rely on it exclusively. Accompanied on this voyage by the astronomer William Wales (who was Charles Green’s brother-in-law and later taught Samuel Taylor Coleridge, the future author of The Rime of the Ancient Mariner), he took every opportunity to determine the longitude by lunars. Much of the value of K1 lay in accurately carrying forward the time from one set of lunar observations to the next, and in “reducing” the longitude of one place to that observed at another. This important process involved comparing the local time observed at a new location with the Greenwich time carried forward by the “watch” from the last place where a good set of lunars had been obtained. By this means the longitude of different locations could be established without the need to take further lunar observations.

  When exploring the New Hebrides archipelago in the South Pacific on this second voyage, Cook listed the extensive lunar observations made by Wales (amounting to several hundred) to fix the longitudes of two ports on separate islands. These, he explains,

  have been reduced by means of the Watch to all the islands, so that the Longitude of each is as well assertained as the two ports above mentioned, as a proof of this I shall only observe that the difference of Longitude between the two Ports pointed out by the Watch, and by the observations did not differ from each other two miles. This also shews to what degree of accuracy these observations are capable of, when multiplyed to a considerable number, made with different Instruments and with the Sun and Stars on both sides of the Moon. . . . If we consider the number of observations that may be obtained in the course of a Month (if the weather is favourable) we shall, perhaps, find this method of finding the Longitude of place as accurate as most others, at least it is the most easiest to put into practice and attended with the least expence to the observer.34

  After discussing the importance of investing in a sufficient number of good “quadrants”—a term that, in his usage, embraced the sextant—Cook offers the following opinion on watches:

  The most expensive article, and what is in some measure necessary in order to come at the utmost accuracy, is a good watch; but for common use, and where the utmost accuracy is not required, one may do without.35

  Cook had no time for the widely held view that lunars were too demanding for the ordinary naval officer:

  this method of finding the Longitude is not so difficult, but that any man with proper applycation and a little practice may soon learn to make these observations as well as the astronomers themselves. I have seldom found any material difference between the observations made by Mr Wales and those made by the officers at the same time.36

  The naturalist Johann Forster may not have been a sailor, but he was a highly intelligent and erudite man, and his comments when the Resolution arrived in New Zealand are of interest in this context:

  . . . I must do justice to our Navigators, who, when we first made the Land, coincided within a few Miles with their accounts, since the last Observation of Longitude: some were not above 3 miles out. This proves more & more the Excellence of this Method of Observing the Longitude by Distances of the Moon from the Sun or some fixed Stars, which has been encouraged by the Board of Longitude & is now so well understood & practised by the Gentlemen of the British Navy.37

  On the return leg of this voyage, Cook measured the difference in longitude between St. Helena (accurately determined by Maskelyne in 1761) and Cape Town (established in the same year with equal care by Mason and Dixon, the British surveyors who later made history by drawing the line dividing Penn
sylvania from Maryland) using both lunars and the watch. Comparing the results with the accepted figure, he found that K1 was in error by 2 miles, while the lunar observations made by Wales were out by just 5—effectively a tie. Given that the longitudinal displacement between the two sites is roughly 24 degrees, and the great circle distance is some 1,800 nautical miles, such tiny discrepancies were insignificant. Cook’s enthusiasm for lunars remained undiminished: “I mention this to shew how near the longitude of places may be found by the lunar method, even at sea, with the assistance of a good watch.”38

  The most important characteristic in a chronometer is that its rate be regular, and therefore predictable: absolute accuracy is neither expected nor required. In this respect K1 was outstanding, constantly gaining between nine and thirteen seconds a day from the Resolution’s arrival in New Zealand in April 1773 until she reached home again in July 1775. In a letter to the Admiralty sent from the Cape of Good Hope on the return voyage, Cook reported that Kendall’s watch had “exceeded the expectations of its most Zealous advocate and by being now and then corrected by Lunar observations has been our faithful guide through all the vicissitudes of climates.”39 K1 accompanied Cook on his third voyage and again performed very well, though two months after Cook’s death it stopped and did not again run reliably until Kendall himself had overhauled it.