Absolute Zero and the Conquest of Cold Read online

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  The most formidable barrier to comprehending cold was established belief, and Bacon's intellectual leadership was crucial to piercing this barrier. His lifelong aim was to be "like a bell-ringer, which is first up to call others to church." Whether exampled by the parish of law or the parish of natural philosophy, for Bacon the goal was "the study of Truth," pursued through the "desire to seek, patience to doubt, fondness to meditate, slowness to assert, readiness to reconsider, carefulness to dispose and set in order." He applied these virtues in the service of the inductive method, the making of proper observations and experiments as a basis for drawing conclusions about the workings of the natural world. His Instauratio Magna announced a "trial" of the "commerce" or correspondence between what humankind believed it knew about the natural world and the true "nature of things," because the goal of bringing the two into congruence was "more precious than anything on earth." To properly contemplate the natural world, he contended, required the rejection of error-riddled previous natural philosophies, particularly that of Aristotle, whose natural philosophy Bacon thought overly based on deductive logic. "I seem to have my conversation among the ancients more than among those with whom I live," Bacon explained in a letter to a friend in Paris, the chemist Isaac Casaubon.

  In Aristotle's view, if one knew the significant "facts" about nature—such as that all things were combinations of the four elements, air, fire, earth, and water—one could deduce whatever humanity needed to know about the world. Aristotle's seventeenth-century followers refused to consider as valid the contemporary experiments investigating or manipulating nature to determine previously hidden properties and causes. Bacon supported such experiments, arguing that "nature exhibits herself more clearly under the trials and vexations of art [forced experimentation] than when left to herself," since nature was like Proteus, the mythical creature who could conceal his identity in myriad shapes until bound in chains, whereupon his true identity was revealed. While Bacon's main target was Aristotle, he also sought to refute artificers such as Drebbel, whose dabblings were based on inconsistent observations and on an absence of rigorous, documented experimentation. "My great desire is to draw the sciences out of their hiding-places into the light," Bacon also told Casaubon. The public considered things to be "marvelous" only so long as their causes remained unknown, he wrote, but "an explanation of the causes removes the marvel," and the business of science must be to identify and explain those causes.

  For the mind to pursue a better understanding of nature, Bacon believed that it must first be purged of preconceptions. Identifying four "idols" of preconception, he railed against them as though he were Jehovah warning his chosen people against the worship of false gods. These were the Idols of the Theatre, a reliance on received philosophical systems, which had perverted the rule of demonstration—that was Aristotle's failing; the Idols of the Tribe, which distorted truth by stressing the correctness of one's own tribe's ideas over those of others; the Idols of the Cave, which prevented individuals from seeing their own defects (principally produced by poor education), so that they looked for sciences "in their own lesser worlds, and not in the greater or common world"; and the Idols of the Marketplace, which used words to deceive the mind, to trick it into thinking that night was day. All these stood in the way of proper research on the cold.

  As antidote to the Idols, a year before his death, Bacon put aside other writings to inscribe, almost in one sitting, a fable of the scientific ivory tower of the future. The New Atlantis was Bensalem, a city on a tropical island that was an unmistakable contrast to Augustine's faith-based "city on a hill." The "lanthorn" (lantern) of this civilization was Salomon's House, run by an "Order ... dedicated to the study of the Works and Creatures of God," an institution alternatively known as the College of the Six Days' Work. The college was organized along the lines of houses of higher learning that Bacon had wished to establish in England, but its laboratories and the attempts of the Bensalemites to command nature bore a distinct resemblance to the facilities and constructions of Cornelis Drebbel and to those of Salomon de Caus, who had designed fantastic gardens for King James.

  In the tale, mariners sailing from Peru became lost in a storm and sought shelter and medical assistance on the island; there the group learned about the work of Salomon's House from one of its elders, a majestic figure whose gaze "pities men." There were vaults, furnaces, laboratory workhouses, and 3-mile-deep caves used for "all coagulations, induracions, refrigerations, and conservations of all natural bodies." Half-mile-tall towers with telescopes allowed observations of "diverse meteors ... winds, rain, snow, hail" and had "engines" for multiplying these natural forces. There were gardens for grafting, and mechanical shops and engineering facilities to build faster means of locomotion and better instruments of war, and to scientifically investigate the motion of birds, so flying machines could be made. The experimenters investigated and imitated all natural phenomena—and then, having understood how nature works, they made flowers bloom out of season and forced water to become ice. The aim of such experiments was to gather data for theorists who would draw "axioms" from it and construct a coherent natural philosophy. The relative weight Bacon gave research and theorizing was displayed by the division of labor at Salomon's House: thirty-three experimenters performed their duties, and just three elders of the community analyzed the experimental results. Beyond distilling the "knowledge of Causes, and the secret motion of things," Salomon's House aimed at "the enlarging of the bounds of Human Empire, to the effecting of all things possible."

  After King James's death in 1625, Bacon was permitted to reside occasionally at Gray's Inn in London, rather than having to remain a dozen miles from the city; and there were further indications that the change in monarchs might completely end his banishment and once again bring him to counsel the crown. In March 1626, while riding in a coach with the physician to the new king, Charles I, Bacon looked at the snow covering the ground and decided to try an experiment to see whether it would preserve the flesh of an animal as well as salt did. That he would even consider such a test is added evidence that at this time natural refrigeration was not generally used for animal flesh. To conduct an experiment was an unusual act for Bacon, whose books mainly featured his analysis of others' work; perhaps writing The New Atlantis spurred him to take a more active role in the investigative process. In any event, he and the physician stopped the carriage near Highgate to go into a poor woman's house and buy a chicken from her, which she quickly dispatched and cleaned at their request. Then the two men returned outside, bent down to the ground, gathered snow, and stuffed and wrapped the carcass with it.

  The snow so chilled Bacon, his onetime secretary Thomas Hobbes later recalled to John Aubrey, who recounts his story in his well-known Brief Lives, that Bacon became too ill to travel and was rushed to the nearby home of the earl of Arundel—the earl then being absent, imprisoned in the Tower of London. Bacon was put into a bed warmed by a pan, but it was a damp bed that had not been used for a year, and his condition worsened. He wrote Arundel, explaining what had happened and citing the ancient story of Pliny the Elder, the Roman historian whose inquisitive sense had drawn him too close to Vesuvius, where the volcanic eruption killed him. Bacon knew he was dying, but in this letter he commented that his experiment into the ability of snow to preserve the flesh of the chicken "succeeded excellently well." Hours after writing this wry note to his host, on Easter Day 1626, Sir Francis Bacon died of pneumonia.

  "In the generation after Bacon's death, many men called themselves Baconians who grasped only the details of his work," writes historian Hugh Trevor-Roper, concluding that "it is the fate of all great men to be quickly vulgarized." The Puritans seized upon Bacon's notion that knowledge must be used for the improvement of human welfare, but they refused to equally honor his other point, that experimentation is required to advance humankind's store of knowledge. During the two civil wars and the dominance of Oliver Cromwell in England, in the 1640s and 1650s, little that chall
enged orthodox views in any arena was tolerated. Only near the end of the Cromwell era, in the late 1650s, did true Baconianism in science resurface, in the formation of a loose cohort of scientific experimenters pledged to Baconian ideals, some of whom met first at Gresham College in London and later at Oxford.

  United in their emphasis on the need to experiment and to push aside the Aristotelian-Augustinian-Aquinan way of apprehending and explaining the world, they took their philosophic cues from Bacon, and from Copernicus as interpreted by Galileo. Aristotle had watched the sun rise in the east and set in the west and deduced the logical conclusion that the sun revolved around the earth; Copernicus and Galileo observed and measured the movements of a greater number of astronomical bodies, applied the tenets of mathematics, and inductively concluded that it was highly probable that the earth revolved on its axis daily and around the sun annually.

  The new "invisible college" group agreed with and admired this startling Galilean conclusion about nature and adopted the mostly inductive method by which it had been reached. Robert Boyle, Robert Hooke, Christopher Wren, and others began to evolve ways of separating valid from spurious experimentation, in the process accelerating the dissolution of magic's thousand-year spell over the realm of explanations of natural phenomena. "Mountebanks desire to have their discoveries rather admired than understood," Boyle charged, but "I had much rather deserve the thanks of the ingenious, than enjoy the applause of the ignorant."

  To deserve the thanks of well-informed people, a scientist's experiments had to be performed in a public though restricted space, before an audience composed of people whose level of knowledge was high enough to properly assess the scientific method and results, but who would not too quickly assert causal explanations of what they saw. And furthermore, for experimental results to be deemed conclusive, the experimenter first had to write his procedures in precise and understandable terms, so that others could replicate the experiment and its results. These Baconian precepts became the basis for establishing in the 1660s the ideal audiences, witnesses, and venues for scientific experimentation: the Royal Society in England and the Académie Royale des Sciences in France, arenas in which scientific work on cold would be judged.

  Though the French institution was modeled on the British one, it was more Baconian, because it was more rigorous in selecting its members, and those members, once elected, were given stipends by the government to devote their energies solely to science. The Royal Society's Fellows had to make their own livings, and had to tax themselves to buy scientific equipment.

  Boyle and other leading Fellows of the Royal Society were able in their various studies to accomplish much more, scientifically, than Bacon himself, in large measure because Bacon had smoothed their path by erasing belief as a barrier to discovery. "The works of God are not like the tricks of jugglers or the pageants that entertain princes, where concealment is requisite to wonder; but the knowledge of the works of God proportions our admiration of them," Boyle could contend. Hooke could express a similar rationale in his ecstasy at finding in his microscope's view natural forms "so small, and so curious, and their design'd business so far remov'd beyond the reach of our sight, that the more we magnify the object, the more excellencies and mysteries do appear. And the more we discover the imperfections of our senses, and the Omnipotency and Infinite perfections of the great Creator."

  The seventeenth-century experimenter who did the most extensive work in the arena of the cold was Robert Boyle. Born a year after Bacon's death, Boyle was the youngest son of an extremely wealthy man, the earl of Cork. In an autobiographical note, Boyle guessed he was the thirteenth or fourteenth child of a mother who died of consumption soon after she gave birth to him, and of a father who died by the time "Robin" was seventeen. He never attended a university, but he studied with private tutors at home and on the Continent. Sickly as a youth, badly injured by what he described as a fall "from an Unruly horse into a deep Place," he was troubled in his adulthood by kidney stones, weak eyesight, and "paralytic distemper."

  Though he was one of the first experimental scientists, Boyle was by modern standards still in thrall to magic and irrational disciplines. He lobbied for repeal of an old law against alchemy because such prohibitions restricted legitimate chemical research, but he was not beyond experimenting with and extolling the healing properties of human and horse manure, was convinced of the medicinal value of ground-up millipedes, and believed astrologically based notions such as that grape juice stains could be washed out of garments most readily at the season when grapes ripened on the vine.

  Boyle initially began his research in the areas of agriculture and medicine but then gravitated to physics and chemistry. Oxford colleagues ribbed him for pursuing chemistry, which "professed to cure no disease but that of ignorance." His chemical research also incensed the Dutch rationalist philosopher Benedict Spinoza, who castigated Boyle in letters to the Royal Society for subordinating reason to experiment and for believing that a chemical combination of particles could act differently than a physical mixture.

  Boyle's large private fortune enabled him to spend liberally to support his studies. No other natural philosopher in England, it was said, could afford the expense of constructing and testing the first—and for some time, the only—vacuum apparatus in existence on the island, fabricated for him by Hooke. Boyle's work on "the spring of the air," published in 1660, secured his scientific reputation. Vacuums led him to conduct research on air pressure, from which he deduced Boyle's law, that the volume of a given amount of a gas at a given temperature is inversely proportional to the pressure to which it is subjected; the greater the pressure, the smaller the volume. At the time he formulated this law, he did not understand all its implications. Nearly two hundred years would pass before the relationship between pressure and volume that Boyle described became the cutting edge of cold research.

  Most later appraisals of Boyle's life ignore his research on cold, though his contemporaries deemed it important, and it remains the first extensive scientific examination of the subject. Sensing that people might wonder why he had spent several years working on the cold, Boyle cited as his guiding rationale Bacon's identification of heat and cold as the right and left hands of nature. Expressing regret that cold had been "almost totally neglected" by classic authors, he also exulted because that neglect provided him with an "invitation [to] repair the omissions of mankind's curiosity toward a subject so considerable." He did so, splendidly, in his 1665 book New Experiments and Observations Touching Cold, Or, An Experimental History of Cold Begun, To Which Are Added, An Examen of Antiperistasis, and An Examen of Mr. Hobs's Doctrine About Cold. Many of Boyle's experiments had been conducted during the extremely frigid winter of 1662, but—the publisher John Crook wrote in a note to readers—the transcriber absconded to Africa and part of the original manuscript had been lost, forcing Boyle to redo some of the experiments and delaying publication. Crook noted he was rushing the book into print for the winter of 1665, so others would have the proper climate in which to repeat Boyle's experiments, should they choose to do so. In Boyle's own introduction, he likened exploring the cold to a physician attempting to do his work in a remote country where there was little help from implements or drugs. Reaching for another analogy, he wrote that the conditions in the far country of the cold might seem "incredible" to readers, as they had for him before he recalled that no one in such a very warm location as the African Congo was able to believe in the existence of ice. Boyle asserted he had "never handled any part of natural philosophy that was so troublesome and full of hardships" as the study of cold. He confessed to having suffered while conducting the experiments, but he reminded readers that sea divers "suffer as much wet and cold, and dive as deep, to fetch up Sponges, as to fetch up Pearls."

  Boyle took as his task the establishment of basic information about the causes and effects of cold. Today it is difficult to imagine just how ignorant people were, as late as the latter part of the seventeenth century, of
how ordinary cold operates. But the refusal of even some of the best minds of that century to accept Galileo's evidence about the earth revolving around the sun meant there was good reason for Boyle to attack what he called myths and misconceptions about the cold.

  To dispel wrong-headed beliefs, Boyle researched every aspect of cold that any reader might wonder about: how one material might transmit cold to another; how atmospheric pressure related to cold; how cold condensed liquids such as oil; how salt, nitre, alum, vitriol (iron sulfate), and sal ammoniac (salt of ammonia) could intensify the cold; how cold could separate chemical solutions into crystals or salts. He made hundreds of experiments to eradicate confusion about the sources of cold, confusion he traced back to two of Aristotle's notions: that observation by the senses of unadorned nature was enough to apprehend the world, and that the source of all cooling in the world was a primum frigidum.

  Had he believed Aristotle's contention that nature abhorred a vacuum, Boyle wrote, he would never have bothered trying to make one; thereafter, he refused to accept any ancient teachings without skepticism. To lead readers to distrust the Aristotelian adage about the evidence of the senses, in his book on cold Boyle reminded readers that tepid water flowing over a heated hand feels cool but actually is not very cold. He also took measurements in all seasons of a certain lake that many Englishmen swore was cooler in summer than in winter—because it certainly seemed refreshingly cool when one swam in it on a hot day—and showed that the lake's temperature was definitely lower in winter than in summer. Where Bacon had tried to refute Aristotle by philosophic opposition to his theories, Boyle added the evidence of experiment to reach the conclusion that the "testimony of our senses easily and much delude [s] us."