The Day the World Discovered the Sun

by Mark Anderson

  Endeavour made it to the mouth of a river—a waterway Cook named Endeavour—where at high tide the bark was beached so the blacksmith and carpenters could begin repairing the wounded vessel. The reef itself, an inspection soon revealed, had saved the entire ship from sinking. The fothering had only closed up part of the hull’s hole. Part of the hull-cutting reef had broken off, and the fothering had inadvertently wedged the coral into place to fill the gap.

  By June 22, all crew members were camped onshore and recuperating from the nearly fatal disaster. Banks, of course, seized the opportunity to collect more specimens. Along with the usual catch of birds and satchels full of plants, Banks and Cook caught glimpses of a beast that was nothing like they’d ever seen before.

  “It was of a light mouse color and the full size of a greyhound,” Cook recorded. “I should have taken it for a wild dog but for its walking or running in which it jump’d like a hare or a deer.”9 According to Tupaia their Tahitian interpreter, whose interpretive skills were weakening as the ship ventured farther and farther away from his native island, the locals called this animal “kangooroo.”

  Banks now turned his sights on hunting the strange animal. The newly discovered marsupial, Banks wrote, “hop[s] upon only its hinder legs, carrying its fore close bent to its breast. In this manner, however, it hops so fast that in the rocky bad ground where it is commonly found it easily beat my greyhound, who, though he was fairly started at several, killed only one and that quite a young one.”10

  Cook concluded, simply, that the kangaroo “proved most excellent meat.”11

  BATAVIA (JAKARTA, INDONESIA)

  October 1770–January 1771

  The repaired Endeavour continued to leak and ultimately required the attention of professional shipwrights in a bona fide naval yard. Cook knew his best chance of surviving passage through the Indian Ocean and beyond the Cape of Good Hope was to refit Endeavour at the Dutch East India Company’s headquarters in Batavia. A ship that probably couldn’t have made the return voyage thus docked at the company shipyards. In Banks’s words, crew members were “rosy and plump” when the ailing ship pulled into port.

  The Dutch had built Batavia in the early 1600s and, naturally, filled the city with canals. Over the ensuing century and a half, however, the stagnant water, sewage, and animal carcasses in the canal made the East India Company capital city a festering swamp of malaria and dysentery.

  During the twelve weeks the shipwrights required to repair Endeavour, all but one of the ship’s crew fell sick at least once. Endeavour’s healthiest shipmate turned out to be John Ravenhill, a sail maker characterized by Cook as a drunk. By Cook’s estimate Ravenhill was “an old man about 70 or 80 years.” Actually Ravenhill was forty-nine.12

  On December 26, when Cook finally weighed anchor and set sail for Cape Town, the captain wrote that Endeavour left Batavia “in the condition of a hospital ship. [We lost] seven men, and yet all the Dutch captains I had an opportunity to converse with said that we had been very lucky and wondered that we had not lost half our people in that time.”13

  Cook would continue losing men on his “hospital ship” as they set sail across the Indian Ocean. (The unhealthy “fresh” drinking water that Endeavour took aboard at Batavia was the likely culprit.)14 During the first two weeks out of Batavia, another seventeen died. Banks’s young artist, Parkinson, died on January 27, 1771. Two days later, Cook recorded in his journal the final passage of his chief astronomer.

  “In the night died Mr. Charles Green who was sent out by the Royal Society to observe the transit of Venus,” Cook wrote on January 29. “He had long been in a bad state of health, which he took no care to repair—but on the contrary lived in such a manner as greatly promoted the disorders he had had long upon him. This brought on the flux which put a period to his life.”15

  Chapter 14

  ECLIPSE

  MISIÓN ESTERO, SAN JOSÉ DEL CABO

  Summer 1769

  The mildly good news, as some of those suffering from the Baja fever began to see, is that ultimately the plague was survivable. “The patient talks somewhat incoherently, yet knows his friends and will answer questions with tolerable distinctness,” the jail fever chronicler said about the third phase of the illness. “In this situation he continues six, seven, eight, nine, ten or eleven days and from which, if the symptoms do not increase, he gradually recovers.”1

  By June 5, Chappe had become both chief astronomer and chief doctor to the mission. “Mr. Chappe had brought with him from France a little chest of medicines and some physic [medical] books,” Pauly wrote. “In this emergency he was an occasional physician. He examined the symptoms of the disease, then consulting his books, he endeavored to find out the proper remedies. But he soon found himself as much at a loss as those who formerly consulted the oracles, whose ambiguous answers frequently admitted of two opposite meanings, and left them as much in the dark as before.”2

  Chappe remained busy in his observatory, too. On the night of June 6, he trained his telescope on Jupiter to mark the time its moon Io crossed behind the planet.3 Chappe notes in his logbook that his observation of Io’s eclipse behind Jupiter was something close to ideal. “Perfect observation,” he wrote.4 The next four nights Chappe was up late observing the “culmination” of the stars Arcturus and Kornephoros (the second-brightest star in the constellation Hercules). An astronomical culmination is the equivalent of solar noon for any given star. It’s the highest point in the sky that a star’s east-west journey carries it on any given night. And just like regular noon, when a star is at its culmination, it’s almost exactly halfway between where it rose in the east and where it’ll be setting in the west. This makes two different, nearly perpendicular angles on the sky.5 So it provides an opportunity to test slight errors in one’s astronomical quadrants. On the night of June 7, Chappe measured both the distance toward the eastern horizon from Arcturus and Kornephoros at culmination. On June 8, he took the same measurement but this time toward the western horizon. Later analysis proved that the quadrant he used to take transit data carried, over wide angles, an intrinsic error of 1 arc minute and 25 arc seconds.6

  During the 9:00 AM and 2:00 PM hours on June 8, Chappe busied himself with careful measurements of the sun to test any slight or subtle drift rates in his pendulum clock. And then on the nights of Friday, June 9, and Saturday, June 10, he went back to using his quadrant to take culmination measurements on Arcturus and Kornephoros again.

  For Chappe, Sundays at the mission were hardly days of rest. Sunday, June 4, the day after the Venus transit, Chappe had been busy both day and night measuring the sun’s motion and Jupiter’s moons to continue collecting data that would pin down both his clock’s exact error rate and his observatory’s longitude. But the following Sunday, June 11, was a different story. This time, as Pauly noted, Chappe “had a violent pain in his side and was delirious at times.”7 Typhus had struck the group’s leader.

  Bouts of fever and delirium came in twenty-six to twenty-eight-hour stretches. “He was forced to prepare his own medicines,” Pauly noted. When he was still well, Chappe had relied on another healthy member of the mission to mix the tonics. But one vial was mistaken for another, and as a result the group’s feverish artist Noël had nearly been poisoned. Chappe wasn’t going to make that mistake again.

  Chappe’s astronomical measurements, of course, stopped. But Chappe also knew that on June 18, one week into his illness, there would be a lunar eclipse. Astronomers all across Europe would be timing the exact moment of the eclipse’s beginning and end. This was the ultimate cure-all for his longitude problem. Chappe had resolved, regardless of his health, to measure the June 18 eclipse with the same precision that had defined his transit data. “It is inconceivable how Mr. Chappe, low as he was, laboring under his malady, weakened by the fever fits he had gone through, could lend as close an attention to this phenomenon as the ablest observer could have done in full health,” Pauly wrote. “Indeed he had much ado to hold ou
t to the end of the observation. He was taken with a fainting fit, and a pain in his head. . . . He desired to be let blood; his interpreter, a surgeon who had never practiced much, and who was himself sick, tried to bleed him but missed. However, encouraged by Mr. Chappe, he tried again and succeeded.”8

  As Pauly observed, “It will be a matter of admiration to look over the account of this observation.” The moon entered the earth’s penumbra (half shadow), Chappe, recorded, at 10:45 PM. At 11:08, Chappe recorded, “the eclipse started, I think, within the minute. The shadow is so clear and the moon is so brilliant, I think I estimated that start time too late.”9 So Chappe picked up the pace. Starting at 11:11 PM and 41 seconds, he began to record the entry of the earth’s complete shadow across every lunar crater he could find. He recorded a stunning thirty-two observations, revealing not only expert offhand knowledge of lunar geography but also a phenomenal stamina in the face of a severe malady. As the eclipse passed its halfway point, and the end of the earth’s shadow was sweeping its way past the same lunar craters, starting at 12:40 AM, Chappe recorded another thirty-four time-stamped observations as the “lighted segment” of the eclipse swept past the Harpalus, Aristarchus, Galileus, Menelaus, and Tycho craters. No doubt shivering and gripped by extraordinary pain, Chappe recorded his final entry for the night at 2:48 AM. “The edge of the moon is perfectly [out of eclipse],” Chappe wrote. “But it still seems smeared.”10

  Ultimately Chappe’s lunar eclipse data was not deemed as useful as his other longitude-determining observations, including both observations of Jupiter’s moons and observations during the Venus transit. But Chappe’s data in aggregate yielded a longitude determination for Misión Estero of 112 degrees, 2 arc minutes, and 30 arc seconds west of the royal Paris observatory—or 109 degrees, 42 arc minutes, and 19 arc seconds west of the Greenwich prime meridian.11 By any measure, this was an impressive result.

  Misión Estero was shuttered the following century, and during its 110 years it had multiple locations within and near San José, so the exact placement of Chappe’s observatory is unknown. But the latitude and longitude that Chappe’s data produced places the crosshairs squarely on the small city itself—as close to spot-on as present evidence can determine.

  After the lunar eclipse, however, Chappe’s condition worsened. In desperation he tried to ride out of the mission on horseback but had to return. “He lay in a most deplorable condition, suffering the sharpest pains, and destitute of all assistance,” wrote Pauly, who was fighting his own case of the fever. “The village . . . was by this time a mere desert. Three-fourths of the inhabitants were dead, and the rest had fled to seek a less infectious air. But the contagion had already spread far and wide.”

  Still, Chappe managed to record nine more days of solar observations to continue refining the accuracy of his timekeeper. In his logbook for June 29, Chappe recorded the brief but revealing confession, “I observed, fatigued by lack of sleep and illness.”12 He stayed up another nine June and July nights, dutifully recording culmination measurements of the stars Arcturus and Kornephoros and immersion and emersion of Jupiter’s moons.

  The smell of death would have been inescapable, as well as the groans of sick and dying explorers and natives. Food remained available during this plentiful season, but picking and preparing, with no healthy servants to call on, was another matter. Chappe didn’t have to venture far to get to his telescope, clock, and quadrant. But finding date palms near the mission whose fruit bunches hadn’t already been completely picked apart was no small challenge for the rare healthy person in this pitiful realm of the dying. Climbing the trees—braving the knife-sharp basal leaves that guard the dates—was difficult enough. Now an unsteady hand, a weak body, and sometimes delirious mind made simple subsistence its own cruel daily punishment.

  The jail fever chronicler described the last phase of the sickness. “Often either from neglect or an improper treatment in the beginning . . . [typhus] puts on a more fatal and alarming form. The pain of the head continues . . . the tongue as well as base of the teeth are covered with a thick black crust and the patient is unable to thrust it out of his mouth and loses the power of speech and of swallowing. . . . The pulse becomes weaker and quicker. . . . The patient is now altogether insensible. . . . He knows not the by-standers. . . . His muscles become flaccid. . . . He is affected with . . . convulsive startings and twitchings of the muscles. . . . His extremities become cold. A final quantity of blood sometimes distills from his nostrils. His face has a livid and cadaverous appearance, and death which soon follows these symptoms puts a period to his sufferings.”13

  On August 1, 1769, the forty-two-year-old Jean-Baptiste Chappe d’Auteroche drew his final breath. On his deathbed Chappe had said, “I feel I have little time to live. But I have fulfilled my purpose, and I die happy.”14

  When he died, Chappe was surrounded by Pauly and Noël, whose own severe illnesses no doubt made them wonder how many days hence they might accompany their superior to the grave. “Doz and Medina did their best to pay last respects to Chappe for the priest was long since dead,” Pauly said. “The Spanish, French and every one of the survivors then collected what little strength they had left and performed the most melancholy of all offices.”

  Chappe had asked Pauly to bury him in a Franciscan habit, a request that the morbidly bedraggled expedition honored. Crucially, Chappe had also charged Pauly with collecting his papers and ensuring their safe passage back to Paris. Fighting his own pain, delirium, and fever, Pauly gathered what journals and logbooks he could find and packed them in a casket, addressing it to the viceroy of New Spain. Pauly instructed one of the local chiefs to ensure the casket make it onto the ship that would be sailing for the mainland in September—should Pauly himself not survive the ensuing month and a half.

  When word of Chappe’s death reached Mexico City, Alzate—the polymath who had so delighted in the visiting Frenchman’s presence five months before—was “greatly affected,” Alzate wrote to the president of the French Royal Academy of Sciences. “New Spain has lost in him a man whose talents would have been of great service, to make known a thousand natural curiosities which here lie buried in oblivion.”15

  Chappe’s colleagues at the Academy of Sciences in Paris could only concur. In the words of Chappe’s eulogist, the academy’s permanent secretary, the deceased “had an open and candid, unpretentious soul, and a noble, straightforward and honest heart; he was naturally lively, gregarious and amiable. He was known in the highest circles; the King himself deigned to converse with him and honored his death with expressions of regret. Never was there one more unselfish than he. He liked fame; he wished to earn its favors, not to steal them. . . . One could only have wished that the last proof he gave, so worthy of praise, had not been fatal to him.”16

  PARIS

  1769–1770

  Pauly and expedition artist Noël survived the cursed voyage, making them two of just nine (out of 28) who returned home. They made their way back to Paris via Mexico City—where the magnanimous viceroy had given them three expense-paid months to fully recover—and on to Vera Cruz and Cadiz. The voyage’s scientific instruments, still property of the Royal Academy of Sciences, were returned to their rightful owners. Chappe’s bereaved brother returned Ferdinand Berthoud’s marine watch to the clockmaker. And Pauly put the contents of that casket full of papers and logbooks into the hands of France’s Astronomer Royal, César-François Cassini de Thury.

  Cassini, as he was known, edited Chappe’s papers and published them three years later in Voyage en Californie pour l’observation du passage de Vénus sur le disque du soleil, a comprehensive volume commemorating the abbot’s journey, reproducing his diaries and logbooks, and publishing the whole of Chappe’s transit-related data. In the same 1772 volume, Cassini also wrote up his own history of the Venus transit and his summary of the data gathered worldwide on June 3, 1769, and its subsequent analysis.

  The Venus transit expeditions of 1761, Cassini said, left
a frustratingly vague answer to the ultimate question of the sun’s distance. (Astronomers used a different number, the solar parallax, as a proxy for distance to the sun. See this book’s Technical Appendix for more details.) “The result of the 1761 transit . . . enlarged the range of [possible parallaxes] from 8 1/2 arc seconds up to 10 1/2 arc seconds,” Cassini wrote. “Thus the speculations of theory are found only too often belied by practice. One finds it very far indeed from the precision forecasted by Mr. Halley.”17

  Fortunately, Cassini noted, 1769 provided the world with a second chance. In fact, he calculated, the magnitude of the 1769 parallax—the difference in transit time at the North Pole compared to the equator—and the favorable locations available to observe it would not be duplicated again for a long time. The next three Venus transits—in 1874, 1882, and 2004—wouldn’t offer nearly as propitious an opportunity to those distant future generations as did the most recent alignment of sun and planets. “It won’t be until 2012 that the transit of Venus will be nearly as advantageous as it was in 1769,” he said.

  However, Cassini said, the many observers sent across the planet to witness the transit left behind an ocean of data. Some of it was good; some was not so good. Cassini argued, though, for concentrating on the most successful expeditions. “Three major voyages which, by their importance and usefulness, should be distinguished here: That of Father Hell to Vardø island, that of M. Chappe to California, and that of the English to the South Seas.”

  Because of his arrival at Vardø seven months before the transit, Cassini noted, Father Hell “had ample time to prepare and make a bountiful harvest of observations of different kinds that we hope to see in interesting detail in the considerable book this scholar promises us.” Still smarting from the war of words between Hell and Lalande, Cassini laced his description of Hell’s expedition with sarcasm—but conceded that Hell had at least provided all the detailed Venus transit data that the academy might require.