The First Scientific American

by Joyce Chaplin

  The French and British, in contrast, had their greatest holdings in North America and none in the Pacific. As their empires expanded and vied in the eighteenth century, the French and British sought a Northwest Passage that would, by heading north, circumvent the Spanish empire. This passage was especially important for the British because they lacked access to the Mississippi and St. Lawrence Rivers, great advantages to the French and Spanish.

  In 1745, Parliament promised £20,000 to anyone who could sail from Hudson’s Bay to the “South Sea,” or Pacific Ocean. Franklin was motivated. He studied accounts of voyages into Hudson Bay. Both Christopher Middleton and Henry Ellis had sailed there between 1741 and 1742 and between 1746 and 1747, respectively. Franklin dismissed their doubts that a further passage flowed out of the bay and concluded that ships might “sail easily” through an “expected Passage.” Then, in 1752, Franklin joined venturers from Philadelphia, Maryland, New York, and Boston. Together, they bought a vessel, the optimistically named Argo, and sent it to Hudson Bay. The men sought geographic knowledge (and the prize) but also wanted to expand trade and fishing in the northern waters that Britain and France disputed. The Argo set out in March 1753, then turned back when ice blocked it as winter set in. A second attempt in 1754 was even less successful. The ship returned to Philadelphia with only some Inuit artifacts for the Library Company.70

  His investment in the Argo revived Franklin’s fascination with the sea and sailors. The Argo’s captain, Charles Swaine, had left his manuscript notes and charts with Franklin before he left on the second attempt. Franklin retained the two journals from the journeys, the relevant “Charts,” and “a Number of Letters and Papers” about the northern venture. All the documents were subsequently lost. But his interest in them showed that he was turning the nautical interests of his boyhood into ones suited to a mature natural philosopher.71

  Franklin also took another look at Atlantic storms, especially the winds within them. In a 1751 letter to Collinson, he remarked on “the more equal temper of sea-water, and the air over it” compared with their counterparts on land. Franklin suggested that the winds “agitated” large bodies of water, which thereby “continually change[d] surfaces,” blending cold and warm waters and creating a general moderation in temperature. To explain why wind blew westward from Africa to America, Franklin declared that the rotating earth was itself moving “West to East, and slipping under the air,” which created an apparent wind. And he concluded in 1753 that it was “a Mistake, that the Trade Winds blow only in the Afternoon.” Instead, they blew almost all the time, making the ocean a constant field of forces. He believed that system could, like magnetic variation, be charted, though perhaps not easily reduced to any single force, such as the rotation of the globe.72

  Franklin next considered something that wind caused, water-spouts. These whirlwinds over water were highly dangerous to wooden sailing vessels. He concluded that a spout formed when opposing currents of warm and cold air collided. The warm air rose and the cold sank, and together, they created a visible vortex. The consequent force sucked upward the surface water around it. Franklin maintained that spouts ascended rather than descended, violently raising water rather than smashing down into it. Others, including Colden, argued that the spouts descended. Franklin insisted on the logic of warm air ascending—“The Rising will begin precisely in that Column that happens to be the lightest or most rarified; and the warm Air will flow horizontally from all Points to this Column, where the several Currents meeting and joining to rise, a Whirl is naturally formed.” It would have been a tall order to Franklin or anyone else to plunge into a waterspout and look up into it in order to see its internal shape. Franklin instead visualized the dynamic by comparing it to the descending motion of a fluid draining out of a tub with a central hole in its base.73

  How did he know anything about waterspouts? It was not clear Franklin had ever seen one. Since he had returned from London in 1726, he had had no excuse to go to sea. (While in Annapolis on postal business in 1755, however, he spotted a whirlwind and remembered that mariners believed waterspouts could be dissipated by firing cannon through them. He tried to “break” the whirlwind by “striking my whip frequently through it, but without any effect.”) But he had a great treasure trove of information in his maritime family, the Bostonians and Nantucketers he had grown up with.74

  He had been quizzing New England mariners for some time. Pehr Kalm, a Swedish naturalist who visited North America from 1748 to 1751, reported that Franklin had, perhaps in boyhood, “heard from sea captains in Boston, who had sailed to the most northern parts of this hemisphere.” (These tales might have nudged Franklin toward the Argo venture.) And Franklin praised his maritime informants. During his work on meteorology in the 1740s and 1750s, for example, he credited “an old Sea Captain” with testimony that there was little thunder and lightning on the high seas and “an intelligent Whaleman of Nantucket” for information about whirlwinds’ occurring to the leeward.75

  Between 1754 and 1755, Franklin dived into written works about hydrography and nautical science. Characteristically, he blended learned and unlearned sources, as when, in 1754, he ordered for the Library Company the volumes of “the Philosophical Transactions” that it lacked as well as a copy of “Dampier’s Voyages.” Each source—the Philosophical Transactions and the Dampier work—is worth consideration.76

  Waterspout. Benjamin Franklin, Experiments and Observations on Electricity (1769). HOUGHTON LIBRARY, HARVARD UNIVERSITY.

  The Royal Society volume of 1753, for instance, included an account of a historic episode in hydrography. In a 1751 letter, Captain Henry Ellis described to the Reverend Stephen Hales the experiments he had done off the coast of West Africa. On the Earl of Halifax , Ellis had tested “ventilators” that Hales had designed to improve the circulation of shipboard air. This work was part of Hales’s effort to use experiments with fluid circulation to benefit humanity (as Franklin did with his Pennsylvanian fireplace). The ship’s ventilators worked: of the 130 people on board the Earl of Halifax, Ellis reported, all were “very healthy.” He then went on to recount his experiment with another Hales invention, a “bucket sea-gage.” This device was an ordinary wooden bucket sealed at top and bottom. Each end was fitted with a unidirectional valve activated by water velocity; the valves opened as the bucket descended and closed when it was drawn up. Weighted and lowered on a line marked at regular intervals, the bucket could take discrete samples of seawater from specific depths.77

  Ellis then analyzed the samples. He used a Fahrenheit thermometer to measure the water temperatures at various depths, ranging from 360 to 5,346 feet—over a mile deep. At the ship’s tropical location, the air temperature was 84 degrees, but the temperature of the water dropped, “in proportion to the depths,” to 53 degrees. It stayed at this temperature, even in samples from lower depths. Ellis also discovered that the water from the lowest depths weighed more and hence was “the saltest water.”78

  It was astonishing. Since the 1660s, natural philosophers had been trying to craft instruments to observe the sea at depths where humans dared not venture. But it was Ellis who, using the Hales sea gauge, recorded the first subsurface temperature measurements in the open ocean. Hales’s inventive instrumentation—very cheap, something a cooper could knock together on board a ship—made it possible to investigate the globe’s hidden reaches. The sea gauge is the electric kite’s watery cousin. Imagine a kite on a mile-long string—it could easily sample the upper atmosphere that fascinated Franklin. Ellis did the same under water. He admitted that he could think of no immediate use for his discovery, other than that it “supplied our cold bath, and cooled our wines or water at pleasure; which is vastly agreeable to us in this burning climate.”79

  The cold baths and wine were chilling in every sense. Ellis commanded a slave ship, and many of the people on the Earl of Halifax were African captives bound for the British West Indies. When he rejoiced that Hales’s ventilators made the passengers h
ealthy, his comparison was to slavers with appalling mortality rates. He was pleased that running the ventilator was “good exercise for our slaves, and a means of preserving our cargo and lives.” In this case, the lives were the cargo. Slave ships were sites for science and for empire.80

  What might Franklin have made of this? In the spring of 1754, he reported that he “perused the 47th Vol. of the Transactions.” It is not impossible that he turned first to the piece on him, one of the accounts of his electrical experiments. That letter ended on page 211, where Ellis’s letter then began. Franklin might have been flattered by his proximity to Hales, whose work on circulation he admired. He had read other Hales publications in the Philosophical Transactions (as in the preceding volume, number 46), knew Ellis from his attempts to find the Northwest Passage, and took an interest in shipboard health. Franklin lamented that many migrants (Germans, felons, and others) arrived in Philadelphia with “gaol fever,” the name for contagions associated with poverty and crowding. In 1755, he urged the Pennsylvania Assembly to outlaw the overcrowding that would “poison the Air those unhappy Passengers breathe on Shipboard, and spread it wherever they land, to infect the Country which receives them.”81

  We know Franklin made a mental note of Hales’s sea gauge—he would use one at sea in 1785. But he could only get so much hydrographic material out of the Philosophical Transactions. Franklin was wise to turn to other sources, such as “Dampier’s Voyages,” that focused on maritime phenomena exclusively.

  William Dampier, privateer, adventurer, and hydrographer, was one of the best-known mariners of Franklin’s day. He had done what Franklin had not, gone to sea as a boy. Dampier circumnavigated the globe three times and was a privateer who harassed enemy vessels on behalf of the Royal Navy. He is best remembered now as the captain who deposited Alexander Selkirk on Juan Fernández Island, giving Daniel Defoe an idea for a book called Robinson Crusoe.82

  But Dampier was also a maritime expert. In 1699, he published an influential Discourse of Winds, Breezes, Storms, Tides, and Currents, the book Franklin ordered in 1754. Like Halley, Dampier had tried to determine what regular patterns, if any, played over the world’s oceans. He postulated that some ocean winds and currents were stable (they “never shift at all”) and that even those that changed did so in regular patterns. He explained that Atlantic currents followed the trade winds, beginning off the coast of Africa and continuing over to the Americas. Yet these wind-driven currents paled in comparison to the one that emerged from “the Gulph of Florida which is the most remarkable Gulph in the World for its Currents.”83

  So the reading material Franklin selected in 1754 gave him two models for hydrographic work. On the one hand, gentleman Henry Ellis flourished his instruments and data; on the other, tarpaulin Dampier recounted his long experience at sea. Despite their different methods, these investigations sometimes yielded complementary results. Gentleman Edmond Halley included “Dampier’s Passage” on his chart of magnetic variation; Dampier returned the favor, using Halley’s thermal explanation of trade winds in his Discourse . But the land-bound Franklin would have to lean toward Dampier’s descriptive mode and to use sailors’ own descriptions to do so.84

  Franklin started to question mariners more pointedly in 1753. Indeed, he made time to do so. In his letter on waterspouts, later read before the Royal Society, he explained that he had postponed writing due to “Business partly, and partly a Desire of producing further Information by Inquiry among my Seafaring Acquaintance.” The seafarers confirmed that waterspouts, like whirlwinds, pulled things up into the air—boats at sea and animals on land. Franklin then credited his “intelligent Whaleman of Nantucket” as well as “some Accounts of Seamen” for this information. He also cited some printed sources. These latter included works by Dampier and Cotton Mather, who had published an essay on whirlwinds in the Philosophical Transactions . The intelligent mariners, who filled in Franklin’s knowledge while he was wrapped up in “Business,” were anonymous sources, certainly not the equals of the published experts.85

  Franklin’s father would have been pleased: his son now thought sailors were his inferiors. At the time he sought information on waterspouts, Franklin began to act as patron to individual seafarers. He was personally responsible for admitting Francis Buckley, “a poor Sailor . . . in a very bad Condition with sore Legs,” to the Pennsylvania Hospital in 1753; Franklin stood “Security” for all charges for Buckley’s treatment and maintenance. He would send a gift in 1761 to Charles Hargrave (or Hargrove), who was at the Royal Hospital for Seamen in Greenwich, England. Hargrave had rendered frequent service to Franklin, as when he carried to Philadelphia David Hall, Franklin’s business partner and relation by marriage.86

  Franklin was ambivalent, as befitted a former artisan who had become a philosopher. He concluded his letter on waterspouts by announcing that he had “not with some of our learned Moderns disguis’d my Nonsense in Greek, cloth’d it in Algebra, or adorn’d it with Fluxions.” He must have realized that this sentence might offend gentlemen who donned all three disguises, so he omitted it when he published the letter. Without this phrase, Franklin’s praise of ordinary and “intelligent” seafarers gave credit to the unlearned without digging too sharply at the learned. Indeed, sailors seemed to value his opinion. William Falconer, a scribbling mariner, cited “Dr. Franklin” as an expert on waterspouts in his Universal Dictionary of the Marine (1769); Falconer had also versified on waterspouts in his sea poem “The Shipwreck” (1762).87

  But Franklin also began to criticize mariners’ trade knowledge. He was dissatisfied with captains’ accounts of waterspouts and wanted them to give “more accurate Observations of those Phaenomena, and produce more particular Accounts, tending to a thorough Explanation.”88

  Inclusive and collaborative when he had done his electrical experiments, Franklin had acquired a hectoring tone and patronizing attitude. He sidled yet further from his plebian origins. He was now confident in his status as gentleman of letters. Franklin would get another boost when the war that everyone had been expecting finally blew up.

  OVER the protests of its Quaker leaders, Pennsylvania threw itself into the French and Indian War (1754–1763), the American phase of the Seven Years’ War. In 1753, Virginia sent a young George Washington, with a small militia unit, to persuade the French to withdraw from the Ohio Valley. The French easily repelled the Virginia band and the larger British threat behind it. That small incident then exploded outward through the colonies, over the Atlantic, and eventually into Africa and South Asia, exacting an unprecedented toll on places, populations, and governmental budgets.

  Many readers of Franklin’s Autobiography wonder why Franklin spent so much time describing his military activities during the French and Indian War, right down to the amounts of provisions he ordered for the troops. He was thorough because the conflict changed everything. Until the end of his life, he lived with the war’s consequences. The great struggle would divide and redivide the world and would incite the initial colonial protests against Great Britain that would culminate in the American War of Independence.

  The Seven Years’ War pitted Great Britain against France and Spain, the main rivals for North America. It also threatened British colonists’ delicate relations with Indians. By the 1750s, the most powerful Indian group was the Iroquois Six Nations. The Iroquois had a much-qualified alliance with the British colonies, represented as a Covenant Chain that bound the two peoples together. “Keep bright the chain” was the ritual exhortation of Anglo-Iroquois diplomacy.89

  Franklin wanted a stronger as well as a brighter chain, which gave him reason to soften, temporarily, his attitudes toward Indians. In 1754, he attended a congress of colonial and Iroquois delegates at Albany, New York. “In our Way thither,” Franklin remembered, “I projected and drew up a Plan for the Union of all the Colonies.” This Albany Plan offered a permanent intercolonial council, drawing representatives from each colony as well as from the Iroquois, and a royally appoin
ted governor over all. Colonists worried that this body would give too much power to the Crown; imperial administrators feared it gave colonists the upper hand. The plan was an interesting harbinger of Franklin’s role in planning pancolonial organizations and the first sign that he took Indians seriously as political actors, not just “Tawney” people who needed to be cleared out of North America. But it was never adopted.90

  Franklin, approaching his fiftieth year, still had vigor enough for the front lines. In 1755, he commanded the troops in Northampton County, located between Philadelphia and the New York-Pennsylvania border. There, he directed construction of three forts over the mountain range that was the hoped-for barrier to Franco-Indian invasion. He had few good things to say about the nearby enemy Indians, yet he admired the “Art in their Contrivance” at keeping warm with fires hidden in depressions in the ground, invisible to spies on the British side.91

  In 1756, Franklin was elected colonel of Philadelphia’s militia regiment, and his military title went to his head. (“The People happen to love me,” he confided to Collinson; “perhaps that’s my Fault.”) His political opponents sniped that his troops’ parading was an “infinite distraction” in the city. Franklin’s men felt differently. After their first muster, they marched him home and saluted him with “some Rounds fired before my Door, which shook down and broke several Glasses of my Electrical Apparatus.” Too much love, perhaps.92

  The republic of letters continued to adore Franklin, too. Of the more technical praise, appreciated by cognoscenti, he confessed to Jared Eliot that he felt quite like a girl with “a pair of new Silk Garters.” The specialized compliments, like silky undergarments, were acquisitions appreciated only by those in the know but were no less pleasing for that. (Franklin roguishly offered to “take the Freedom to show them” to Eliot.) In late 1755, he became a corresponding member of London’s Society (later Royal Society) of Arts, which gave premiums for new devices and useful discoveries. He received another honorary master’s degree, this from the College of William and Mary, which confirmed the spread of his fame up and down the colonial seaboard.93