6. The Age of Wonder, by Richard Holmes, pp. 144-182

Balloonists in Heaven, 7-12; Herschel Among the Stars, 1

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Lunardi did little to advance ballooning as a serious scientific pursuit, but the man who made the second ascent in Britain, James Sadler, was more in earnest about it. He was by trade a baker and confectioner in Oxford, but he was also an amateur chemist and an inventor. He raised money for his balloon attempts from the Oxford undergraduates who patronized his confectionery business, and built both a fifty-foot-tall Montgolfier hot-air balloon and a smaller hydrogen balloon. In the first, he took a thirty-minute flight in October 1784 -- the second British flight -- and in November ascended in the hydrogen balloon, which was equipped with scientific instruments. Unfortunately, the wind was too brisk and Sadler had to jettison the instruments when the balloon tore apart after seventeen minutes. Sadler escaped with bruises, but still proclaimed the hydrogen balloon the better one.

Sadler then proclaimed his intent to fly across the English Channel. Samuel Johnson, visiting Oxford, had hoped to witness Sadler's flight but was too ill. He died less than a month later. Perhaps having heard of Sadler's loss of his instruments, Johnson "presented (or probably bequeathed) to Sadler an enormously expensive barometer" that the balloonist kept and used on later flights, even though he was tempted to sell it to raise funds. 

In France, Jean-Pierre Blanchard, who had hoped to be the first aeronaut, was experimenting with ways to steer a balloon, including his moulinet, a hand-cranked propeller. In 1784 he came to London in search of financing, and made several ascents in a hydrogen balloon. One of his backers, a member of the Royal Society named John Sheldon, equipped him with scientific instruments for a flight, but Blanchard through them overboard when he had trouble getting over the rooftops of London. Blanchard finally teamed up with John Jeffries, an American physician who had been a military surgeon for the British during the Revolutionary War.

Jeffries, who wanted to be elected to the Royal Society, saw ballooning as primarily a scientific endeavor, and proposed four points to be studied: the control of ascent and descent; the direction of the course of the balloon; the nature of the atmosphere at varying heights; and shedding "new light on the theory of winds in general." In November 1784, he and Blanchard made a flight across the Thames that was the first to accumulate significant amounts of data. It demonstrated that balloon flight was not a simple parabola but a series of ascents and descents as the balloon struggled for equilibrium. Jeffries then agreed to finance a flight from Dover to France.

Blanchard and Jeffries were not the only contenders for the first trans-Channel flight. Sadler had to give up when his balloon was destroyed by a rainstorm as it was being transported on a barge on the Thames from Oxford. Pilâtre de Rozier had the backing of the French court and the Académie des Sciences, but while he was waiting at Boulogne for favorable winds, rats ate at the balloon canopy. Blanchard and Jeffries had their own difficulties, partly caused by Blanchard's ego -- he wanted to to fly solo, and tried to trick Jeffries by wearing a lead-weighted belt which would enable him to claim that Jeffries was weighing down the balloon and that Blanchard would have to proceed alone. Jeffries caught on to the trick, however. Blanchard then insisted that Jeffries's scientific instruments were too heavy, and forced him to proceed with only a barometer and a compass.

On January 7, 1785, Blanchard and Jeffries made their ascent from Dover cliff for a two-hour flight across the Channel. When they began to lose altitude over the water, they jettisoned everything they could -- the ballast, their food, and everything except the barometer and a bottle of brandy. They were still too low for the cliffs of the Pas de Calais, so they began removing their clothes until they were in their underwear. The barometer went, too, but not the brandy. The striptease worked: As they reached the cliffs, they rose and caught the onshore wind, traveling twelve miles inland. But their course was taking them toward a forest, where a crash-landing in the trees could be fatal. So Blanchard suggested one last way of lightening the load: They urinated into the leather bladders that they had kept as potential flotation devices and threw them overboard. It was just enough to take them over the treetops. In his account of the flight, Jeffries apologized for telling the story of urinating into the bladders, but maintained it was of scientific import. Holmes, however, observes in a footnote that the volume of urine probably wouldn't have been sufficient, and suggests that they must have defecated as well. "No doubt Jeffries felt that this last detail was too much even for scientific candour."

Rescued by a crowd that had been following their descent on horseback, they were celebrated in Paris, where Jeffries in particular was honored by Benjamin Franklin, with whom he "spent several quiet evenings ... discussing the future of flight, and the beauty and intelligence of French women." He was also elected to the Royal Academy but received no other honors from the British government. He made no other flights, and in his diary he expressed relief that he had survived. Blanchard, on the other hand, made a total of sixty-three flights, none of them of scientific consequence.

The fatal Channel-crossing attempt of Pilâtre in 1785

Ballooning began to wane in popularity, especially after the disastrous attempt by Pilâtre de Rozier to cross the Channel the other way, from Boulogne to Dover, in June 1785. He attempted to combine in a single craft both a hot air balloon and a hydrogen balloon. There is some evidence that he had reservations about this potentially "lethal combination of highly inflammable gas and naked flame." The weather was not the best, and at the last moment he persuaded a third person not to attempt the flight with him and his co-pilot, Pierre Romain. As the balloon rose and drifted toward the cliffs, sparks ignited the hydrogen that Pilâtre was venting from the upper balloon. Both men were killed in the crash. Pilâtre's death, followed by the accident the next year when Ralph Heron became entangled in the ropes of Lunardi's balloon, "discredited ballooning with the British public for a generation," although the French continued to experiment, especially with the military potential of balloons. There were tales of French military balloonists taking their girlfriends up in balloons, "so the first Mile High Club was also formed." Napoleon took four balloons to Egypt in 1798, but they were destroyed the following year in the battle with Nelson at Aboukir Bay. "Military balloons were not used again in any conflict until the American Civil War.

In 1810, James Sadler returned to ballooning and an attempt to cross the Irish Sea, a more difficult flight than the English Channel. On a practice flight over the Bristol Channel, he encountered wind turbulence and in his efforts to lighten the basket was forced to throw overboard Dr. Johnson's barometer, to his great regret. In October 1812, he tried to cross from Dublin to Liverpool, but was caught in winds that swept him northward over the sea. He tried to ditch into the sea, but a passing boat refused to rescue him for fear of getting tangled in the balloon's rigging. So he dropped his emergency ballast and relaunched -- a unique maneuver -- until he finally located a second boat that was willing to attempt a rescue. Sadler's feats attracted the attention of Shelley, who in the winter of 1812 launched several small balloons, each of which carried his pamphlet "A Declaration of Rights," and wrote a sonnet about the experience. Finally, in 1817, Sadler's son, Windham, made the crossing from Dublin to Wales, a five-hour, sixty-mile journey. Like his father, Windham was a firm believer in the scientific value of ballooning, but he was killed in a balloon accident in 1824, when he was twenty-seven. His father, James, never flew again.

Although the enthusiasm for balloons waned, some scientific benefit was attained. The French chemist Joseph Gay-Lussac experimented with high ascents, and his trip to 23,000 feet above Paris in 1804 helped establish the limit at which humans can breathe. Exploration of the sky also awakened interest in meteorology, leading to Luke Howard's study and classification of clouds in 1804, which established the basic types of clouds: cumulus, stratus, cirrus, and nimbus and their various combinations. Howard was elected to the Royal Society in 1821. The interest in clouds was reflected in the art of Turner and Constable, and the poetry of Coleridge and Shelley. "It could be argued that the Romantics actually invented the idea of 'the weather' itself, as it now preoccupies us; as well, of course, as 'inner weather.'" Ballooning also led to advances in mapping, and the creation of the British Ordnance Society, the first state mapping program. 

The Royal Society under Joseph Banks was, on the whole, more interested in astronomy than in ballooning. And in 1785 Herschel began his project to create most powerful telescope ever. The octagonal tube would be 40 feet long and five feet in diameter, and have two or even three mirrors, ranging in diameter from 36 to 50 inches. Because of it its size -- higher than a house -- it would have to be specially constructed to resist the wind, as well as the extremities of weather. The viewing platform for the astronomer (Herschel) would be dangerously high, and the assistant (Caroline) would have to be housed in a special booth with a communications tube to the astronomer. And it would be very, very expensive.

"It was one of Sir Joseph Banks's most dramatic diplomatic coups that he had convinced the King to announce a grant by September 1785." The sum was £2,000 for construction and four years' expenses. In 1786, Herschel, Caroline, and Alexander moved to The Grove, a country house in the village of Slough owned by the Baldwin family, where they began construction on the observatory. Sometime that summer they were visited by an American, the fifty-year-old John Adams, who discussed the possibility of extraterrestrial life with Herschel. Adams was fascinated by the idea, and by its implications for traditional Christianity, believing that if life existed elsewhere, then the Christian ideas of the fall and redemption became absurd. Years later, he would write to Thomas Jefferson urging him not to hire British scientists to teach at the University of Virginia because too many of them -- unlike Herschel -- were orthodox Christians: "They all believe that great Principle which has produced this boundless universe, Newton's universe and Herschel's universe, came down to this little ball, to be spit upon by the Jews. And until this awful blasphemy is got rid of, there never will be any liberal science in the world." (I wonder how many of the current right-wing fundamentalists who idolize the Founding Fathers would react to this?) 

Adams was only one of the flood of visitors who distracted Herschel from the construction of the telescope. In July 1786, he was sent by the king to personally install one of his telescopes at the University of Göttingen, a gift of the king. Caroline was left to supervise the construction, attend to the household, and try to get her own astronomical observations done. She soon decided that she couldn't do all of it. "She would be an astronomer, not a housekeeper." William had built her a small telescope of her own, which "was not suitable for deep space, but it was perfectly designed to spot any strange or unknown object moving through the familiar field of 'fixed stars.'" And with it, on August 1, she discovered a comet. Only about thirty comets had been identified by that time, half of them by the French astronomer Charles Messier, so this was a significant discovery.

On August 6, a delegation consisting of Banks, Secretary to the Royal Society Charles Blagden, and Lord Palmerston came to Slough to see Caroline's comet. The result was celebrity for Caroline independent of her brother's. "The idea of a female astronomer intrigued people." Fanny Burney came to visit, and wrote, "The comet was very small, and had nothing grand or striking in its appearance; but it is the first lady's comet, and I was very desirous to see it." Caroline was, however, rather distant with Fanny. She hit it off better with, of all people, Nevil Maskelyne, who took her work seriously. As did others, after she discovered a second comet in December 1788. "Her reputation continued to grow, especially in France and Germany."

Work on the telescope continued, but in 1787 Caroline, who kept track of the finances, realized that they were facing a financial crisis that could doom the whole project. Joseph Banks came to their rescue again, suggesting that they give a Royal Telescope Garden Party for publicity and fund-raising. On August 17, George III and Queen Charlotte, and a host of royals and other dignitaries came to The Grove to witness what had been accomplished. The event "had the subtle effect, just as Banks would have foreseen, of further publicly committing the King to the scheme for which he was the acknowledged benefactor."

The publicity stunt put Herschel in a good position to request the additional funds, but he also dared to suggest that Caroline might also receive a royal stipend as his assistant. "No British monarch had ever granted a woman a salary, or even a pension, for scientific work before." The suggestion was made, perhaps by Banks, that the stipend might come from Queen Charlotte. On August 23, Banks was summoned to the palace and informed that he would renew Herschel's grant for a total of £2,000 plus an additional £50 per annum for Caroline:  "the first professional salary ever paid to a woman scientist in Britain." But the king also made it clear that he was annoyed at the request for additional funds, and at the garden party that had put him in the position of having to grant the request. He made it clear that this was the last penny he was going to spend on the telescope.

Banks was shaken by the vehemence with which the king expressed himself -- it was only a year before the madness of George III would begin to became apparent. But he was forced to communicate the king's severity to Herschel, who was upset and considered scrapping the project. Caroline was indignant, especially at the penny-pinching accounting rules that Banks said needed to be put in place. The relationship with Banks recovered, but not that with the king. Not until the Prince Regent took over for his incapacitated father did Herschel receive further honors, and although he was knighted in 1816, his £200 stipend remained the same, though its value was cut in half by inflation. 

5. The Age of Wonder, by Richard Holmes, pp. 114-143

Herschel on the Moon, 8; Balloonists in Heaven, 1-6

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Herschel and his brother Alexander became telescope manufacturers, starting with the five seven-foot reflectors they made for George III as royal gifts. Mirror-making remained hand-crafted, but in the course of a decade they turned out 200 mirrors for the seven-foot telescopes, 150 for the ten-foot, and eighty for the twenty-five-foot telescopes. Their customers were wealthy, and included German princes as well as Napoleon Bonaparte's brother Lucien, the Emperor of Austria, and the King of Spain, who commissioned one for the Madrid Observatory in 1806 that cost £3,500.

Herschel's celebrity attracted visitors to the observatory at Datchet. Samuel Johnson urged Susannah Thrale to visit: "What he has to show is indeed a long way off, and perhaps concerns us little, but all truth is valuable and all knowledge pleasing in its first effects, and may subsequently be useful."

Despite visitors and manufacturing orders, he continued his observations, developing a technique of "sweeping" the sky that consisted of moving "slowly up and down, while the constellations turned through the field of observation as the stars moved steadily across the night sky." It was a highly accurate technique that was also very slow: "A complete sweep could take several years to complete." Herschel's familiarity with the sky, which he could read "like a skilled musician sight-reading a musical score," helped him spot any anomalies in his observations. He also began to write about the process of observation itself, including comments on the nature of the eye.

Caroline compiled his remarks on practical observation. After the move to Datchet in 1782, he began to train her even more into an "assistant-astronomer," responding to William's "imperious shout" whenever he wanted her to write down a new observation. She was expected to respond with military precision to his instructions, and her work was essential: "at no point would William have to compromise his night vision by looking at a lit page and taking his own notes." It was cold and demanding work. "They began at eleven at night, and often did not go to bed before dawn, in a mixed state of exhaustion and euphoria.... Herschel took to rubbing his face and hands with raw onions to keep out the cold.... Caroline layered herself in woollen petticoats."

There were also risks: In the harsh winter of 1783, William was almost blown off of the scaffolding that held his twenty-foot reflector, and the frame collapsed on him so that he had to be rescued from underneath it. In December of that year, Caroline was running to record one of William's observations, tripped on one of the stakes that held the guy ropes for the scaffolding, and impaled herself on the iron hook on top of the stake. It "entered my right leg about six inches above the knee," she wrote later, and the workmen couldn't remove her from the hook "without leaving near 2 oz. of my flesh behind." But they didn't call the doctor: She bandaged the wound herself and was back at work two weeks later. "It seems that the extreme cold had an antiseptic effect on the large, open wound, and prevented fatal gangrene." A week after the accident, Dr. James Lind inspected the wound and prescribed an ointment for it. (Lind was one of Shelley's favorite teachers at Eton.) Though the wound finally healed by summer, Caroline suffered pains from it in old age.

In 1784 and 1785, Herschel "drew together his most radical ideas about the cosmos, and published two revolutionary papers in the Royal Society's Philosophical Transactions." He challenged the idea of a firmly fixed cosmos, and from his study of nebulae "for the first time suggested that many, if not all, of these must be huge independent star clusters or galaxies outside our own Milky Way." As for the Milky Way, "his later calculations produced the now-familiar discus shape ... with its characteristic arms spinning out into space, and the slight bulge of stars at its centre." In "On the Construction of the Heavens," he made the radical observation that "The heavenly 'construction' was not something architecturally fixed by the Creator, but appeared to be constantly changing and even evolving, more like some enormous living organism." His assertions had the effect of "hugely increasing the sense of the actual size of the cosmos."

He began to plan the construction of a forty-foot telescope with a four-foot mirror. And in his 1785 paper for the first time credited Caroline in print as the discoverer of "a small 'associate nebula' in Andromeda."

Meanwhile, as the British were surging ahead in astronomy, the French were making their own advances -- in ballooning. Banks heard about what they were up to in 1783 from Benjamin Franklin, who was a member of the Royal Society as well as the American ambassador to France. The French, he reported, were experimenting with lofting giant paper bags made by a paper manufacturer, Joseph Montgolfier. And then a member of the Académie des Sciences, Alexandre Charles, took things a step further by inflating a silk bag, six feet in diameter, that floated from the Champs de Mars across the Seine and drifted fifteen miles away from Paris before it burst. "This was a distance which a horseman could barely a horseman could barely cover in an hour." Charles's balloon had been filled with a newly discovered gas known as "inflammable air."

Montgolfier recovered from Charles's triumph by sending up a hot-air balloon with a wicker basket that contained a sheep, a duck, and a cockerel. It stayed in the air for seven minutes and the animals returned to earth safely. The logical next step was to send up a human being. Banks was skeptical about the experiments but recognized that they could lead to something useful, such as a "flotation device" that would make carriages and wagons lighter so that horses could pull them faster. "This aptly suggests how difficult it was, even for a trained scientific mind like Banks's, to imagine the true possibilities of flight in those early days."

The "inflammable air" that Charles had used to fill his balloon had been discovered by the English chemists Henry Cavendish and Joseph Priestley. But it was the French chemist Anton Lavoisier who repeated and refined their experiments, producing the gas from iron filings combined with sulfuric acid. He named the product "hydrogen." The Montgolfier brothers, Joseph and Étienne, followed developments in chemistry because of their paper-making business, so when they heard about this lighter-than-air gas, they speculated about using it to fly paper bags. "As early as 1782, Joseph had humorously suggested the theoretical possibility of flying an entire French army into Gibraltar, and seizing it from the English."

The Montgolfiers' first manned flight

The trouble with hydrogen is that "it was slow and dangerous to produce, potentially explosive, and easily escaped from containers made of silk or animal bladders." Hot air was easy to produce and could be contained within silk and paper -- Joseph Montgolfier said he "discovered the principle of hot air by watching his wife's chemise inflating when she hung it over the hearth to dry." The Montgolfiers first large hot air balloon, launched on June 5, 1783, was thirty feet high and 110 feet in circumference. It contained 22,000 cubic feet of hot air, rose to 60,000 feet and stayed up for ten minutes.

A twenty-nine-year-old doctor named Jean-François Pilâtre de Rozier persuaded the Montgolfiers to let him be the "test pilot" in their first manned flight on November 21, 1783. The balloon was seventy feet tall, powered by a brazier burning straw, and had a circular gallery instead of a basket for the passengers. There had to be two of them, one on either side, to balance the balloon. Pilâtre de Rozier's "co-pilot" was the Marquis d'Arlandes, an infantry major. The flight lasted twenty-seven minutes and took them across the Seine.

The launch of Alexandre Charles's hydrogen balloon

But although this was the first manned flight for the record books, the one made ten days later by Alexandre Charles is more significant for its technical breakthroughs. It was a hydrogen balloon whose silk skin had been treated with rubber. It had a valve at the top of the balloon through which the gas could be vented, and ballast bags filled with sand that could be jettisoned to control the balloon's ascent. He and an assistant, M. Robert, went up from the Tuileries Gardens on December 1, 1783.  Benjamin Franklin watched the ascent through a telescope. The flight lasted two hours and traveled twenty-seven miles. When they landed, Charles asked Robert to get out of the basket first, but the release of his weight sent the balloon aloft again, traveling to 10,000 feet in just ten minutes. Charles kept his head, however, and made notes until it grew too cold for him to hold a pen. He slowly released the hydrogen and landed again in thirty-five minutes, only three miles from the original landing spot. "It was the first solo flight in history."

Back in Britain, George III expressed his interest in getting his country into ballooning. Banks was still unconvinced that the French achievements had any practical applications, but he was definitely intrigued. William Watson Jr. had seen one of the unmanned test flights before the Montgolfiers' first manned launch, and excitedly wrote to Herschel about it. Herschel immediately thought about the possibility of using balloons to carry telescopes high into the upper air. Others began to think of the sinister side of ballooning. The novelist Horace Walpole feared the conversion of balloons into "new engines of destruction to the human race."  Benjamin Franklin recognized the military potential of aircraft and calculated that five thousand balloons, each carrying two men, could result in an airborne invasion from France.

But by the summer of 1784, the balloon craze had spread to England. "Unmanned and then manned ascents took place in almost every large city in the kingdom -- London, Oxford, Cambridge, Bristol, Edinburgh." And a twenty-five-year-old Italian, Vincent Lunardi, began to capitalize on the British enthusiasm for balloons. He made his first ascent in London on September 15, 1784, with a crowd of 150,000 as witnesses. "Lunardi drifted north-westwards across London and into Hertfordshire, eating legs of chicken and drinking champagne, and occasionally trying to 'row' his balloon with a pair of aerial oars." But his balloon had no release valve, so he had to try to snag something on the ground with a grappling anchor to end his flight, which he did in a field just outside of Ware.

When he returned to London, "a curiously modern publicity machine began to roll. He sold exclusive rights to his story, and an in-depth interview, to the Morning Post." He was introduced to the king and given a watch by the Prince of Wales, souvenirs of his flight were marketed, and he became the toast of fashionable London. Banks, on the other hand, was unimpressed, and privately referred to Lunardi as "a charlatan." Samuel Johnson was also critical of the hype that surrounded Lunardi, even before the flight, pointing out that buying a ticket to the launch was foolish because "in less than a minute they who gaze at a mile's distance will see all that can be seen." He also expressed skepticism about Lunardi's claim that he would be able to steer the balloon with his oars -- and he was correct. As for ballooning in general, he pointed out that since it couldn't be steered effectively, a balloon failed to "serve any purpose of communication; and it can give no new intelligence of the state of the air at different heights, till they have ascended above the height of mountains, which they seem never likely to do."

Another sensation was caused by Lunardi in June 1785 when he proposed to take the actress Mrs. Sage, who was a rather large woman, and a young man named George Biggin aloft with him. Mrs. Sage was to be the "First Aerial female." But the weight of the three passengers and the elaborate and showy trappings that had been attached to the gondola proved too much for the balloon, so Lunardi jumped out, leaving the two passengers to conduct the flight themselves.

Unfortunately, in his haste to depart, Lunardi failed to do up the lacings of the gondola's door. As the balloon sailed away over Piccadilly, the crowd were treated to the provoking sight of the beautiful Mrs Sage on all fours in the open entrance of the gondola. The crowd assumed that she had fainted, and was perhaps receiving some kind of intimate first-aid from Mr Biggin. 

After Mrs. Sage's flight, cartoonists indulged in ribald speculation

In fact, Mrs. Sage was trying to lace up the door, but when she regained her feet, she stepped on the barometer and broke it, so there was no way to measure how high they flew. So they drifted on, eating cold chicken and drinking Italian sparkling wine, until they landed in a field near Harrow, where they were threatened by an angry farmer and had to be rescued from him by the schoolboys from Harrow School. Afterward, there was ribald speculation about what may have happened between Biggin and Mrs. Sage during the flight. "Gallantly, Mr Biggin refused to comment."

The lack of scientific value of Lunardi's flights became the subject of criticism, and his reputation suffered in 1785 when a young man, Ralph Heron, became entangled in the ropes during a launch at Newcastle, was carried a hundred feet into the air, and fell to his death.

23. Mason & Dixon, by Thomas Pynchon, pp. 733-773

Three: Last Transit, 75-78

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Mason writes Dixon to tell him, "I am coming North a Mountain of suitable Gravity to seek, whose presum'd Influence might deflect a Plumb-line clearly enough to be measur'd without Ambiguity," adding a little dig about Maskelyne's "difficult History with Plumb-lines." He asks Dixon to recommend an inn, but Dixon insists that Mason stay with him.

"Mason finds Dixon still gloomy about the death of his Mother back in January," but they begin to reminisce. Mason tells him about how Maskelyne kept him on in Ulster longer than necessary and then brought him home on "a meat-ship" -- a vessel loaded with sheep carcasses. Eventually there comes a moment of unaccustomed tenderness between the old companions:

"Gave thee a rough time, didn't I, Friend." Reaching to rest his hand for a moment upon Dixon's Shoulder, before removing it again.
"Oh," Dixon nodding away at an Angle from any direct view of his Partner's Face, "as rough times go, ... the French were worse ...? The five Years of Mosquitoes, of course ..." The old Astronomers sit for a while in what might be called an Embrace, but that they forbear to touch. 

Dixon launches into an account of his stay at the North Cape of Norway, where he caught only glimpses of the transit. And then proceeds into a tall tale about his travels even further north, but to the inside of the world, where one of the inhabitants observes that people on the outside of the globe, "wherever you may stand, given the Convextity, each of you is slightly pointed away from everybody else, all the time, out into that Void that most of you seldom notice. Here in the Earth Concave, everyone is pointed at everyone else, -- ev'rybody's axes converge, -- forc'd at least thus to acknowledge one another, -- an entirely different set of rules for how to behave." Mason has his usual bemused reaction to Dixon's fabulations.

As they part, Mason asks, "If they don't kill and eat me up there, shall we do this again." Dixon replies, "We must count upon becoming old Geezers together." "They are looking directly at each other for the first time since either can remember."

In Scotland, in August 1773, Mason meets up with Samuel Johnson and James Boswell, who are "upon their famous Trip to the Hebrides," or so Cherrycoke claims, though Ives doubts that they passed within a hundred miles of each other. "'I had my Boswell, once,' Mason tells Boswell, 'Dixon and I. We had a joint Boswell. Preacher nam'd Cherrycoke. Scribbling ev'rything down, just like you, Sir.'" On his expedition, Mason locates the mountain called Schiehallion, but he declines to return to the mountain to make the measurements needed, so Maskelyne gets the credit for determining the mass of the Earth.

When Mason and Dixon meet again, Dixon is crippled by gout and Mason has rediscovered his old melancholy. They spend their time together fishing. Mason meets Dixon's mistress, Margaret Bland, whom he has always planned to marry "just before we go to America." They have two daughters, but "America now would never be more real than his Remembrance, which he must now take possession of, in whatever broken incompleteness, or lose forever." Mason tells Dixon that he has remarried and they have had a child, Charles Jr., and are expecting another.

While they are fishing one night, they're approached by a dog, a Norfolk terrier, who looks like the Learnèd Dog, though that was many years ago and this dog is "scarcely a year old." The dog follows them home, but never speaks. Margaret Bland asks what his name is. "'Fang,' says Mason. 'Learnèd,' says Dixon." Then one night, both of them have the same dream: The dog whispers to them, "I am a British Dog, and belong to no one, if not to the two of you. The next time you are together, so shall I be, with you." They take it as a sign that they'll see the dog when they get together next year.

But it is Mason, not Dixon, who emigrates to America, where Benjamin Franklin visits him on his deathbed. "His illness at the end was never stipulated. Yet 'tis possible, after all, down here, to die of Melancholy." Though he had five more boys and a girl, "he never put Rebekah to Earth." And he never really reconciled with his father, who claimed that Mason's son Doctor Isaac "was named after the Doctor who lost" Rebekah. Willy Mason tells his brother, "You are nam'd for Newton, whom Dad admires greatly," but Doctor Isaac remains unsure.

"When news reach'd Mason that Dixon had died, he went about for the rest of the Day as if himself stricken." He tells his sons stories about Dixon, and when he mentions Dixon's two daughters, Willy and Doc suspect him of matchmaking: "'Two Sons.... Two Daughters. And a Father wishing, as Fathers do, to be a Grand-Father." With Doc, Mason visits Dixon's grave, where "Mason beseech'd what dismally little he knew of God, to help Dixon through." When he is suddenly overcome, "'It's your Mate,' Doctor Isaac assur'd him, 'It's what happens when your Mate dies.'"

On his deathbed, Mason says to Franklin, "Sir, you have encounter'd Deists before, and know that our Bible is Nature, wherein the Pentateuch, is the Sky. I have found there, written ev'ry Night, in Astral Gematria, Messages of Great Urgency to ourTime, and to your Continent, Sir."

After Mason's death, "Mary would return to England with the younger Children, -- William and Dr. Isaac, Rebekah's Sons, would stay, and be Americans."