The First Scientific American

by Joyce Chaplin

  It is worth noting a political difference. Wilson identified with his aristocratic patrons and had no record, as Franklin did, of complaining about the British government. In contrast, Franklin’s loyalties lay with the middling sort and with the Whigs, indeed, the Club of Honest Whigs; his steady if moderate criticism of British authorities had become the hallmark of his political career. There was no politically inflected difference in the two men’s theories of electricity. And the two behaved themselves for the most part, never stooping to insults, as Franklin had done with Hillsborough. But their political antipathy would certainly add verbal sparks to their exchange over lightning rods. It also belied Franklin’s assertion, when members of the APS had misbehaved, that the Fellows of the Royal Society never took partisan positions against each other.81

  In August 1772, the Royal Society committee inspected the magazine yet again and then met four times. Neither Wilson nor Franklin budged, but the doctor carried the day, probably because he, unlike Wilson, offered experimental evidence, which convinced the committee members. They advised the Board of Ordnance to attach two lightning rods to each building within the Purfleet magazine. Each was grounded by a lead pipe buried in the ground and then fastened to an iron rod—with “a sharp point” terminating in copper. Outvoted, Wilson asked Franklin to reconsider his position. “I will never give it up,” Franklin replied. (The former friends never reconciled.) Wilson filed a minority report, which accompanied the advice to use pointed conductors to the Council of the Royal Society and then to the Board of Ordnance.82

  After this thunderous affair, Franklin calmed himself by investigating how oil had a calming effect on water. As usual, this was a problem he had been considering, on and off, for more than a decade. He had first noted the phenomenon on shipboard in 1762 when, needing some light, he rigged up an “Italian” lamp, a glass tumbler “slung in wire” and containing water topped with a layer of oil and a wick. Franklin hung the lamp from his cabin’s ceiling and watched it sway. He related to John Pringle in December 1762 that, even as “the water under the oil was in great commotion, rising and falling in irregular waves,” the oil followed an unexpectedly different pattern: “The surface of the oil was perfectly tranquil, and duly preserved its position and distance with regard to the brim of the glass.” “We are all agog,” Pringle responded, “about this new property of fluids.” The 1769 edition of Experiments and Observations included the letter on the new property.83

  What was the new property? Franklin marshaled his trademark blend of sources: books, artisanal knowledge, and direct observation. He remembered reading, in his youth, Pliny’s description of the smoothing effects of oil and “wondered to find no mention of them in our Books of Experimental Philosophy.” Where the philosophers failed, mariners excelled. Franklin had received reports of oil’s calming effect on water from “an old Sea Captain” as well as a witness in Newport, where spilled whale oil kept the harbor’s water smooth as glass.84

  But sea folk were not always helpful. Franklin recalled his transatlantic voyage in 1757. He had observed the smoothness in the wake of two ships in the fleet bound for Louisbourg and queried Captain Walter Lutwidge, who had just used him as ballast in his experiments relading the ship. Ludwidge responded impatiently: “‘The Cooks, says he, have I suppose, been just emptying their greasy Water thro’ the Scuppers, which has greased the Sides of those Ships a little.’” Franklin had felt humiliated: “This Answer he gave me with an Air of some little Contempt, as to a Person ignorant of what every Body else knew.”85

  His own demonstrations were more satisfying. He started with the rather placid pond on Clapham Common, London. On the windward side, just where the air began to make the water shudder, Franklin poured oil and saw it instantly erase the ripples. From this observation, he drew yet more proof of matter’s particulate nature; when they touched water, a “mutual Repulsion” among the particles of oil sent them skidding over its surface, ready to rebuff the breeze in a way water could not do. He explained that “the Wind blowing over Water thus covered with a Film of Oil, cannot easily catch upon it so as to raise the first Wrinkles” that led to waves. Franklin was entranced by his discovery and commemorated it with a clever invention. He transformed the top of his walking stick into a receptacle for oil, handy whenever he and the right kind of breeze arrived together at a body of water.86

  He decided that oil should be effective on large bodies of water as well. He knew from Captain Cook that violent surf could prevent boats from reaching shore. But perhaps a ship could sail back and forth off the “Lee Shore, continually pouring Oil into the Sea” until it subsided. There was only one way to find out. On a “blustring unpleasant Day” in October 1773, he tested his theory near Portsmouth, accompanied by Banks and Solander, Cook’s naturalists—three men in a boat. In a near storm, they made several “Trips of about half a Mile each, pouring Oil continually out of a large Stone Bottle.” The test was inconclusive (not enough oil, perhaps), though Franklin congratulated his companions for their “Patience and Activity that could only be inspired by a Zeal for the Improvement of Knowledge.” Then, he wrote up his findings in a long, much-delayed letter to William Brownrigg, who would present it to the Royal Society.87

  But in December 1773, soon after Franklin had poured oil over the water near Portsmouth, irate Bostonians poured tea over Boston harbor. The exotic goods flowing out of India had become a problem. The recent Tea Act, the one surviving part of the Townshend Duties, had lowered the cost of East India Company tea. This step, it was hoped, would guarantee sales for the troubled company. Only the restive North Americans could see the lowering of prices as reason for revolt. Cheaper tea be damned—the colonists hated the Tea Act’s monopoly, which undercut colonial profits from smuggled Dutch tea. Massachusetts residents had for some time been leading the most truculent protests against any and all British commercial policies. Now, they made tea with muddy, salty water. They had destroyed private property, and British officials lost patience with them.

  Things seemed to be at an impasse, but Franklin was determined, still, to reach a compromise. He worked on a peace commission, whose members included Fothergill, to broker a repeal of certain taxes in exchange for colonists’ cooperation with commercial regulation. In March 1773, he repeated his claims about the value of the colonies—their growing populations, their ability to consume, produce, and transport valuable goods—to make sense of the Boston affair. Cooperation between colonists and British officials was a necessity, he said, and British force was ill advised. “A Coast, 1500 Miles in Length,” he warned, “could not in all Parts be guarded, even by the whole Navy of England.” Franklin even offered to pay for the destroyed tea, which would have cost him a ruinous £9,000. The gesture made clear that, however unruffled he appeared on the surface, he boiled within and was desperate for resolution.88

  Franklin finally saw why colonists might feel driven to unlawful defiance. He himself began to fear persecution. He worried that his enemies might manipulate the postal system to block the colonists’ access to information and even feared that officials would divert his letters to British ministers and put copies about to prove him treasonous. In 1772, he and William Franklin had wondered whether their private letters were being opened. (William even suspected Anthony Todd of snooping, though his father defended the man.)89

  And then, Franklin suffered the worst humiliation of his life. It was his own fault—he had himself interfered with the circulation of the mail. Londoner Thomas Whately had, years earlier, received several letters from Massachusetts friends, including Thomas Hutchinson and Andrew Oliver. (Hutchinson was chief justice and lieutenant governor; Oliver was secretary.) The two men wrote how they wished to use more forceful action against the intransigent Bostonians, perhaps by removing government from popular control.

  Someone (still unidentified) sent the letters to Franklin, and he forwarded them to Thomas Cushing, speaker of the Massachusetts Assembly. They considered the letters to be evidenc
e of a British plan to destroy colonial autonomy. Franklin advised Cushing, probably ingenuously, against printing the letters, but they were published in Boston in 1773. The publication angered both those who feared what the correspondence said and those who deplored that a private correspondence had become public. On Christmas Day in 1773, Franklin identified himself as the source of the miscirculated letters in order to prevent suspicion from falling on others.90

  Franklin’s confession came only nine days after the Boston Tea Party—bad timing. Even British moderates were turning against colonists. Were none of them dutiful? That a deputy postmaster for North America would read and circulate private letters was a serious matter. Called to account for his actions, Franklin prepared carefully for a hearing in late January 1774, where he would face questioning in the “Cockpit,” where the Privy Council held public meetings.

  Circulation, one of the great themes of his life, had turned toxic. As the crisis surrounding the circulation of the mail drew to a climax, Franklin was obsessed with the common cold and how it circulated. In one 1773 letter, he fretted about both colds and the Hutchinson letters, running from one topic to the next in a revealing train of thought.91

  To a series of correspondents, Franklin wrote letters in which he rejected most of the conventional wisdom on colds. He insisted that they had “no Relation to Wet or Cold,” the proverbial causes that encouraged people to stay indoors, sweltering in wraps or bedclothes. Even doctors recommended these tactics, but Franklin thought they prevented a healthy flow of air and moisture through the body. “No one ever catches the Disorder we call a Cold, from cold Air”; sailors were healthy despite their damp surroundings. Conversely, going out into fresh air caused vigor, as did exercise proportioned to diet. Franklin assumed that the body perspired even if it was cold, which did not entirely close the pores and cause illness. He argued that a different kind of circulation explained colds—people circulated them. “People often catch Cold from one another when shut up together in small close Rooms, Coaches, &c. and when sitting near and conversing so as to breathe in each others Transpiration.”92

  Franklin thus revisited several of his earlier concerns about circulation, including the metabolic cycles of the human body, the movement of air in enclosed atmospheres, perspiration and respiration, and the effects of hot and cold. His interest in the circulation of air was partly rekindled by Joseph Priestley’s chemical work. As Priestley investigated air, he explored its contribution to life, the question Boyle and Hales had investigated earlier. Tormenting yet more small animals, Priestley watched a lone mouse in a bell jar die in tortured gasps as it depleted its air supply. But he gave one lucky mouse a mint plant for company, and it lived. When Priestley related that plants could thus “repurify” foul air, Franklin marveled that “the vegetable creation should restore the air which is spoiled by the animal part of it.” He hoped the discovery would “give some check to the rage of destroying trees that grow near houses.” Instead of being unhealthy, trees might impart health.93

  But Franklin’s long manuscript notes on the common cold, circa 1773, drew no clear conclusion. He did define a cold as “a Siziness [viscosity] and thickness of the Blood, whereby the smaller Vessels are obstructed, and the Perspirable Matter retained.” That matter then “offends [the body] both by its Quantity and Quality.” It is not surprising that Franklin thought impeded circulation caused ill health. But what caused or prevented this thickness and slowness of the blood?94

  Franklin guessed himself into circles. Warm rooms were healthy unless they overheated a body; fresh air helped except when it did not. Colds resulted from exposure to cold air “without Exercise,” yet exercising in a “close Room” could increase the chances of a cold because the exertion might “fill the Air with putrid Particles.” Nor was going outside any safer, as colds resulted from “cooling suddenly in the Air after Exercise.” Other culprits might include wet newspapers, putrid fish, damp books, failing to relieve the bladder frequently, intemperance in eating and drinking, and exposure to rotten glue. Franklin looked everywhere for clues: the high mortality in the Black Hole of Calcutta, the rate at which Pennsylvania reapers drank water, and the fact that American Indians slept with their feet to the fire (retaining health), and that “Hottentots” greased themselves (courting illness).95

  These principles—gathered from Franklin’s long inquiry into circulation and from the expanding geography of the British empire—defy synopsis, let alone analysis. They exist almost as diary entries. In one, Franklin first read Tryon on temperance; in another, he saw Indian spies keeping warm on American frontiers; and then, he pondered questions about labor and perspiration in Pennsylvania’s wheat fields. Franklin may have given the best summary of the issue when he concluded, with Poor Richard’s epigrammatic, if mocking, common sense, that “People often don’t get Cold where they think they do, but do where they think they do not.” He had asked a question about nature he could not answer. Given his history of near-fatal colds and pleurisies, he surely would have welcomed an answer. Having thus undermined his confidence in himself, mind and body, Franklin entered the Cockpit for the hearing on the Hutchinson affair. 96

  It was a denunciation. If Franklin had hoped to reprise his brilliant performance in the question-and-answer interview in Parliament eight years earlier, he had deceived himself. In fact, he had little opportunity to defend his conduct at all—it was, he said later, like a “bull baiting.” Before a packed audience, Solicitor General Alexander Wedderburn lambasted him at length, leaving no opportunity for rebuttal or counterattack. Wearing his best suit, Franklin, who had just turned sixty-eight, managed to remain standing with an impassive expression for the hour that it took Wedderburn to wreck his reputation as a servant of the British empire.

  Devastatingly, the solicitor general attacked each of the accomplishments that had elevated Franklin to the status of philosopher and genius. Poor Richard’s astronomy took a hit when Wedderburn sneered that “the rank in which Dr. Franklin appears, is not even that of a Province Agent: he moves in a very inferior orbit.” Twice, Wedderburn mocked the master electrician with his own terminology by calling him the “prime conductor” in the affair. (As Franklin left, he grasped hands with fellow electrician Priestley, who knew the nerve Wedderburn had struck.) Worst of all was a vicious pun—Franklin’s nefarious work in the postal service had so compromised him, Wedderburn claimed, that “he will henceforth esteem it a libel to be called a man of letters.”97

  Franklin’s status as a member of British officialdom was destroyed. Two days later, Anthony Todd dismissed him from the Post Office. It was a humiliating end to twenty years of service and no thanks for his having helped make American postal delivery turn a profit rather than suffer continual losses. Postal service had been Franklin’s first imperial role, his first significant political function. It had become second nature to him; at least once after his termination, he automatically dropped an unfranked letter into the post, forgetting he had lost his franking privileges.98

  Friends rallied and tried to console him. Some Philadelphians used electricity to burn effigies of Hutchinson and Wedderburn. But Franklin had entered a state of controlled rage against the British government. He never emerged from it. In a “Letter from London” printed in the Boston Gazette in April 1774, Franklin dismissed the service that had dismissed him, warning that “the post officers will in a little time become as formidable as the Commissioners of the Customs and their numerous levee.” The former postmaster was no longer conciliatory: “Behold Americans where matters are driving! ”99

  MAYBE it comforted Franklin that, over at the Royal Society, it was as if nothing had happened. In June 1774, five months after the Cockpit hearing, William Brownrigg presented the society with Franklin’s experiments on pouring oil over turbulent water. During a peaceful moment in the British empire, Franklin had introduced himself to the Royal Society of London with a bang—with a paper on thunder and lightning. Now, as the empire collapsed, he woul
d take his leave of London with a farewell paper on how to calm troubled waters.

  Franklin’s demonstration of oil on water, like his electrical experiments, was dramatic and easily done and hence widely imitated. In early 1775, Thomas Percival reported that the experiment was successfully repeated in Manchester; in Birmingham, Matthew Boulton “astonished our rural philosophers exceedingly by calming the waves a la Franklin.” The quick popularization of Franklin’s new experiment—and its association with him—meant that the world now had two dramatic images of Benjamin Franklin: he was the modern Prometheus who drew fire from the skies in the “Philadelphia experiment,” and he was a wise old man who could calm the raging seas “a la Franklin.”100

  But even Franklin could not calm the political storm rising over the British Atlantic. So far had Anglo-American relations deteriorated that, beginning in 1774, everyone assumed letters and packages carried on British packets were being opened. In a showily sentimental letter to his sister Jane (meant to reproach anyone else who read it), Franklin complained that “the Letters between us, tho’ very innocent ones, are intercepted. They might restore me yours at least, after reading them.” Even the republic of letters suffered. When John Winthrop wrote Franklin to acknowledge a letter and new volume of the Royal Society’s Philosophical Transactions, he related that the once-sealed package was now “only tied up loosely . . . without any seal.”101