This was way sillier than I expected it to be, even having been primed by several of his other books.

I think I'm most impressed by Pynchon's ability to adopt the 18th century vernacular and wield it to articulate the disgusts felt by Englishmen for the barbarity of the United States. It seems like fully half of the novel takes place in taverns and meanders far into territories wholly unrelated to surveying.

The story is told as a sort of bedtime story by the Philadelphian Reverend Cherrycoke appeasing his nephews and niece. It begins with his account of how Charles Mason and Jeremiah Dixon became entangled with each other. Two decades before the 1786 wintery eve from which Cherrycoke speaks, Mason and Dixon meet ahead of their commission about the HMS Seahorse to astronomically observe the transit of venus. Retiring to an ale house after discussing their respective backgrounds, we are immediately met with FENDER-BELLY BODINE HE'S BACK BABY and a talking dog.

Cherrycoke recounts the Seahorse's travel through the English channel, down the coast of France (during which they are attacked by a French warship), and then back up to Plymouth, England to address the numerous casualties sustained by the crew (but sparing Mason, Dixon, and ofc Cherrycoke who lived to tell the tale).

After conspiratorial paranoia about themselves perhaps being french targets, the Seahorse ventures out again, this time accompanied by a second defending frigate. During this trip, Mason holds rememberance for the second anniversary of his wife's death (he gets scary quiet).

The Seahorse arrives in Cape Town, SA where M&D are told not to stoke any political activism in the colony's slave population. At their B&B, Mason becomes the target of the mother's attempts to coerce him into sleeping with a slave to produce a fairskinned offspring to be sold. M&D wind up stranded in Cape Town during the transit of Venus, and Mason must continually rebuff the mother and her horny ass daughters.

Eventually, they find passage on HMS Mercury which takes them to St. Helena where they run into one of Mason's exes (Florinda). They also encounter Nevil Maskelyne (real guy) who they both find insufferable and a little bit insane. They do some astronomy and muse about clocks. Dixon departs for Cape Town, and Mason is stuck with Maskelyne. By the time Dixon returns, Mason is rumored to have became involved with all of the daughters, the mother, and a slave during his stay on the Cape, much to Mr. Vroom's (the husband/father/owner) chagrin. Dixon saves Mason from getting blasted away and takes good ol cornelius out to get good and drunk.

Mason tells Dixon how he first met his wife Rebekah at a cheese-rolling festival which is hilarious in its earnest presentation. He continues to be haunted by her visitations. They eventually make their way to Jamestown, where Mason meets Florinda's ex-fiance who gives him a tour. He convinces Mournival to arrange Dixon's arrival from Cape Town. Supernatural voice of Mason travels across the Atlantic to Dixon.

They eventually both return to England until Mason's mentor dies, effectively resulting in his immediate promotion. His death is discussed at a pub where everyone is in a tizzy about the 1752 English conversion to the Gregorian calendar which caused them to skip from 9/2 -> 9/14 and just miss the interstitial 11 days. Mason visits his fathers house and is reacquainted with his two sons and a lady who tries to convince him to give up stargazing and remarry her, stay home and father his sons. This just reminds him of how nice it was that Rebekah appreciated his profession.

Dixon, too, visits his own mentor William Emerson who apparently has gotten mixed up with the Jesuits (there is no worse fate for an 18th C Englishman). At Emerson's local pub, they digress into discussions of China.

After a year and a half apart, Mason and Dixon meet again in London in 1763. Over ale, Dixon conveys his sympathy for the loss of Bradley and Mason reveals that Bradley had been en route to Plymouth to see them off on their ill-fated first journey aboard the Seahorse. They head to America.

Visiting an apothecary in Philadelphia, the two men meet Benjamin Franklin, who invites them to a coffee-house, a veritable hot-bed of insurrection and revolutionary talk and proceeds to quiz Mason on Dixon's association with the Jesuits and Dixon on Mason's association with Bradley and the East India Company. The episode concludes with Franklin ushering the two men into a carriage that will convey them to Virginia and a meeting with one Colonel Washington.

At Mt. Vernon, the two men enjoy a late afternoon drink, snacks, and some marijuana with George Washington. The discussion ranges between Judaism, Chief Pontiac, the demarcation of western lines by the French and British, and the telluric plates left by one Celeron de Bienville in his efforts to claim territory. Upon their return to Philadelphia, they engage Dr. Franklin anew and he speculates on their shared goals and the Sino-Jesuit connection that Franklin and others believe is intent on creating a communications network across the continent.

In late December 1763, the astronomers complete the first of their tasks as assigned by the Commissioners: establish the southernmost limit of the city of Philadelphia.

The duo awake one morning and find the city abuzz with news of the Paxton Boys' massacre of Native Americans at Lancaster, not far from Philadelphia. Reminded of the violence on the Cape, and spooked by the militant attitude of the local citizenry, the two men wonder aloud how they might avoid both Paxtons and Indians during their journey west.

A subsequent episode covers a full year of work by the astronomers, opening in January 1764 with the reverberations of the massacre and the attack on Fort Pitt still being felt. Mason and Dixon make their base of operations south of the city near the house of John Harland. There, they erect a new base of observation and proceed to mark off the Tangent Line. The work occasions a discussion of the history of the boundary dispute and various mathematical and political attempts to set the line.

Mason and Dixon make separate journeys to the site of the Lancaster massacre and endure the specter of racial violence and the suspicion of the locals.

The Reverend's audience once more raises objections to his story based on historical facts, while the Rev'd himself maintains that history is preserved not in universal acceptance of one story but in the propagation of different interpretations by novelists, playwrights, and poets.

They have many more adventures in America:

The Reverend's brother-in-law, LeSpark, reveals that he briefly encountered the astronomers in the private ridotto of the iron-monger, slave-holder, and inveterate gambler Lord Lepton. Lepton, who fled England to escape his gambling debts, entertains the surveyors at his private castle in the Pennsylvania country side. With concubines purchased from the Canadian convent the Widows of Christ, Lepton's debauched party takes on a hellish air that unnerves the surveyors and makes them anxious to flee.

Dixon proposes to steal one of Lepton's iron bath tubs as compensation for the twenty pounds he believes were unfairly taken from him during a night of gambling. Using magnetic principles taught to him by Emerson, he and Mason attempt to steal the tub but are distracted first by one of Lepton's servants who reminds them of a previous acquaintance and then by the appearance of a pentacle that unpleasantly connects Lepton to the massacre at Lancaster. They make a hasty departure, having taken on new party members, including an electric eel they presently begin to use as a compass.

There's also a mechanical duck insistent on tracking the French chef Allegre. Allegre proposes that the Duck's obsession with him is tied to its paradoxical evolution, in which it both ascends beyond the realm of limited physical ability and is simultaneously bound to more earthly motivations. Mason inevitably and perhaps subconsciously links the Duck's passage from one world to the next, and Vaucanson's efforts to understand the resulting change, to his own feelings on Rebekah's passing. The Duck, its powers augmented by the negative energy of the line and obsessed with a decoy the party have created and placed upon it, becomes a permanent resident of it.

On the continued journeys westward through Pennsylvania, perpendicular to Delware, Mason tells Dixon how he visited the missing eleven days that were canceled when England adopted the Gregorian calendar in 1752. He found himself "alone in the material World".

Upon conclusion of their commission, they return to England, decline further assignments with one another, observe the return transit of Venus, and mostly drink.

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