2. Cold
In the early summer months of 1834, a three-masted bark vessel named the Madagascar sailed into the port of Rio de Janeiro, its hull filled with the most implausible of cargo: a frozen New England lake. The Madagascar and her crew were in the service of an enterprising and dogged Boston businessman named Frederic Tudor. History now knows him as “the Ice King,” but for most of his early adulthood he was an abject failure, albeit one with remarkable tenacity.
“Ice is an interesting subject for contemplation,” Thoreau wrote in Walden, gazing out at the “beautifully blue” frozen expanse of his Massachusetts pond. Tudor had grown up contemplating the same scenery. As a well-to-do young Bostonian, his family had long enjoyed the frozen water from the pond on their country estate, Rockwood—not just for its aesthetics, but also for its enduring capacity to keep things cold. Like many wealthy families in northern climes, the Tudors stored blocks of frozen lake water in icehouses, two-hundred-pound ice cubes that would remain marvelously unmelted until the hot summer months arrived, and a new ritual began: chipping off slices from the blocks to freshen drinks, make ice cream, cool down a bath during a heat wave.
The idea of a block of ice surviving intact for months without the benefit of artificial refrigeration sounds unlikely to the modern ear. We are used to ice preserved indefinitely thanks to the many deep-freeze technologies of today’s world. But ice in the wild is another matter—other than the occasional glacier, we assume that a block of ice can’t survive longer than an hour in summer heat, much less months.
But Tudor knew from personal experience that a large block of ice could last well into the depths of summer if it was kept out of the sun—or at least it would last through the late spring of New England. And that knowledge would plant the seed of an idea in his mind, an idea that would ultimately cost him his sanity, his fortune, and his freedom—before it made him an immensely wealthy man.
At the age of seventeen, Tudor’s father sent him on a voyage to the Caribbean, accompanying his older brother John, who suffered from a knee ailment that had effectively rendered him an invalid. The idea was that the warm climates would improve John’s health, but in fact they had the opposite effect: arriving in Havana, the Tudor brothers were quickly overwhelmed by the muggy weather. They soon sailed north back to the mainland, stopping in Savannah and Charleston, but the early summer heat followed them, and John fell ill with what may have been tuberculosis. Six months later, he was dead at the age of twenty.
Frederic Tudor
As a medical intervention, the Tudor brothers’ Caribbean adventure was a complete disaster. But suffering through the inescapable humidity of the tropics in the full regalia of a nineteenth-century gentleman suggested a radical—some would say preposterous—idea to young Frederic Tudor: if he could somehow transport ice from the frozen north to the West Indies, there would be an immense market for it. The history of global trade had clearly demonstrated that vast fortunes could be made by transporting a commodity that was ubiquitous in one environment to a place where it was scarce. To the young Tudor, ice seemed to fit the equation perfectly: nearly worthless in Boston, ice would be priceless in Havana.
The ice trade was nothing more than a hunch, but for some reason Tudor kept it alive in his mind, through the grieving after his brother’s demise, through the aimless years of a young man of means in Boston society. Sometime during this period, two years after his brother’s death, he shared his implausible scheme with his brother William, and his future brother-in-law, the even wealthier Robert Gardiner. A few months after his sister’s wedding, Tudor began taking notes in a journal. As a frontispiece, he drew a sketch of the Rockwood building that had long enabled his family to escape the warmth of the summer sun. He called it the “Ice House Diary.” The first entry read: “Plan etc for transporting Ice to Tropical Climates. Boston Augst 1st 1805 William and myself have this day determined to get together what property we have and embark in the undertaking of carrying ice to the West Indies the ensuing winter.”
The entry was typical of Tudor’s whole demeanor: brisk, confident, almost comically ambitious. (Brother William was apparently less convinced of the scheme’s promise.) Tudor’s confidence in his scheme derived from the ultimate value of the ice once it made its way to the tropics: “In a country where at some seasons of the year the heat is almost unsupportable,” he wrote in a subsequent entry, “where at times the common necessary of life, water, cannot be had but in a tepid state—Ice must be considered as out doing most other luxuries.” The ice trade was destined to endow the Tudor brothers with “fortunes larger than we shall know what to do with.” He seems to have given less thought to the challenges of transporting the ice. In correspondence from the period, Tudor relays thirdhand stories—almost certainly apocryphal—of ice cream being shipped intact from England to Trinidad as prima facie evidence that his plan would work. Reading the “Ice House Diary” now, you can hear the voice of a young man in the full fever of conviction, closing the cognitive blinds against doubt and counterargument.
However deluded Frederic might have seemed, he had one thing in his favor: he had the means to put the broad strokes of his plan in motion. He had enough money to hire a ship, and an endless supply of ice, manufactured by Mother Nature each winter. And so, in November 1805, Tudor dispatched his brother and cousin off to Martinique as an advance guard, with instructions to negotiate exclusive rights to the ice that would follow several months later. While waiting for word from his envoys, Tudor bought a brig called the Favorite for $4,750 and began harvesting ice in preparation for the journey. In February, Tudor set sail from Boston Harbor, the Favorite loaded with a full cargo of Rockwood ice, bound for the West Indies. Tudor’s scheme was bold enough to attract the attentions of the press, though the tone left something to be desired. “No joke,” the Boston Gazette reported. “A vessel with a cargo of 80 tons of Ice has cleared out from this port for Martinique. We hope this will not prove to be a slippery speculation.”
The Gazette’s derision would turn out to be well founded, though not for the reasons one might expect. Despite a number of weather-related delays, the ice survived the journey in remarkably good shape. The problem proved to be one that Tudor had never contemplated. The residents of Martinique had no interest in his exotic frozen bounty. They simply had no idea what to do with it.
We take it for granted in the modern world that an ordinary day will involve exposure to a wide range of temperatures. We enjoy piping hot coffee in the morning and ice cream for dessert at the end of the day. Those of us who live in climates with hot summers expect to bounce back and forth between air-conditioned offices and brutal humidity; where winter rules, we bundle up and venture out into the frigid streets, and turn up the thermostat when we return home. But the overwhelming majority of humans living in equatorial climes in 1800 would have literally never once experienced anything cold. The idea of frozen water would have been as fanciful to the residents of Martinique as an iPhone.
The mysterious, almost magical, properties of ice would eventually appear in one of the great opening lines of twentieth-century literature, in Gabriel García Márquez’s One Hundred Years of Solitude: “Many years later, as he faced the firing squad, Colonel Aureliano Buendía was to remember that distant afternoon when his father took him to discover ice.” Buendía recalls a series of fairs put on by roving gypsies during his childhood, each showcasing some extraordinary new technology. The gypsies display magnetic ingots, telescopes, and microscopes; but none of these engineering achievements impress the residents of the imaginary South American town of Macondo as much as a simple block of ice.
But sometimes the sheer novelty of an object can make its utility hard to discern. This was Tudor’s first mistake. He assumed the absolute novelty of ice would be a point in his favor. He figured his blocks of ice would “out-do” all the other luxuries. Instead, they just received blank stares.
The indifference to ice’s magical powers had prevented Tudor’s brother William from lining up an exclusive buyer for the cargo. Even worse, William had failed to establish a suitable location to store the ice. Tudor had made it all the way to Martinique but found himself with no demand for a product that was melting in the tropical heat at an alarming rate. He posted handbills around town that included specific instructions on how to carry and preserve the ice, but found few takers. He did manage to make some ice cream, thereby impressing a few locals who believed the delicacy couldn’t be created so close to the equator. But the trip was ultimately a complete failure. In his diary, he estimated that he had lost nearly $4,000 with his tropical misadventure.
—
THE BLEAK PATTERN of the Martinique voyage would repeat itself in the years to come, with ever more catastrophic results. Tudor sent a series of ice ships to the Caribbean, with only a modest increase in demand for his product. In the meantime, his family fortunes collapsed, and the Tudors retreated to their Rockwood farm, which like most New England land had very poor agricultural prospects. Harvesting the ice was the family’s last best hope. But it was a hope that most of Boston openly ridiculed, and a series of shipwrecks and embargoes made that ridicule seem increasingly appropriate. In 1813, Tudor was thrown in debtor’s prison. He penned the following entry in his diary several days later:
On Monday the 9th instant I was arrested . . . and locked up as a debtor in Boston jail. . . . On this memorable day in my little annals I am 28 years 6 months and 5 days old. It is an event which I think I could not have avoided: but it is a climax which I did hope to have escaped as my affairs are looking well at last after a fearful struggle with adverse circumstances for seven years—but it has taken place and I have endeavoured to meet it as I would the tempest of heaven which should serve to strengthen rather than reduce the spirit of a true man.
Tudor’s fledgling business suffered from two primary liabilities. He had a demand problem, in that most of his potential customers didn’t understand why his product might be useful. And he had a storage problem: he was losing too much of his product to the heat, particularly once it arrived in the tropics. But his New England base gave him one crucial advantage, beyond the ice itself. Unlike the U.S. South, with its sugar plantations and cotton fields, the northeastern states were largely devoid of natural resources that could be sold elsewhere. This meant that ships tended to leave Boston harbor empty, heading off for the West Indies to fill their hulls with valuable cargo before returning to the wealthy markets of the eastern seaboard. Paying a crew to sail a ship with no cargo was effectively burning money. Any cargo was better than nothing, which meant that Tudor could negotiate cheaper rates for himself by loading his ice onto what would have otherwise been an empty ship, and thereby avoiding the need to buy and maintain his own vessels.
Part of the beauty of ice, of course, was that it was basically free: Tudor needed only to pay workers to carve blocks of it out of the frozen lakes. New England’s economy generated another product that was equally worthless: sawdust—the primary waste product of lumber mills. After years of experimenting with different solutions, Tudor discovered that sawdust made a brilliant insulator for his ice. Blocks layered on top of each other with sawdust separating them would last almost twice as long as unprotected ice. This was Tudor’s frugal genius: he took three things that the market had effectively priced at zero—ice, sawdust, and an empty vessel—and turned them into a flourishing business.
Tudor’s initial catastrophic trip to Martinique had made it clear that he needed on-site storage in the tropics that he could control; it was too dangerous to keep his rapidly melting product in buildings that weren’t specifically engineered to insulate ice from the summer heat. He tinkered with multiple icehouse designs, finally settling on a double-shelled structure that used the air between two stone walls to keep the interior cool.
Tudor didn’t understand the molecular chemistry of it, but both the sawdust and the double-shelled architecture revolved around the same principle. For ice to melt, it needs to pull heat from the surrounding environment to break the tetrahedral bonding of hydrogen atoms that gives ice its crystalline structure. (The extraction of heat from the surrounding atmosphere is what grants ice its miraculous capacity to cool us down.) The only place that heat exchange can happen is at the surface of the ice, which is why large blocks of ice survive for so long—all the interior hydrogen bonds are perfectly insulated from the exterior temperature. If you try to protect ice from external warmth with some kind of substance that conducts heat efficiently—metal for instance—the hydrogen bonds will break down quickly into water. But if you create a buffer between the external heat and the ice that conducts heat poorly, the ice will preserve its crystalline state for much longer. As a thermal conductor, air is about two thousand times less efficient than metal, and more than twenty times less efficient than glass. In his icehouses, Tudor’s double-shelled structure created a buffer of air that kept the summer heat away from the ice; his sawdust packaging on the ships ensured that there were countless pockets of air between the wood shavings to keep the ice insulated. Modern insulators such as Styrofoam rely on the same technique: the cooler you take on a picnic keeps your watermelon chilled because it is made of polystyrene chains interspersed with tiny pockets of gas.
By 1815, Tudor had finally assembled the key pieces of the ice puzzle: harvesting, insulation, transport, and storage. Still pursued by his creditors, he began making regular shipments to a state-of-the-art icehouse he had built in Havana, where an appetite for ice cream had been slowly maturing. Fifteen years after his original hunch, Tudor’s ice trade had finally turned a profit. By the 1820s, he had icehouses packed with frozen New England water all over the American South. By the 1830s, his ships were sailing to Rio and Bombay. (India would ultimately prove to be his most lucrative market.) By his death in 1864, Tudor had amassed a fortune worth more than $200 million in today’s dollars.
Three decades after his first failed voyage, Tudor wrote these lines in his journal:
This day I sailed from Boston thirty years ago in the Brig Favorite Capt Pearson for Martinique: with the first cargo of ice. Last year I shipped upwards of 30 cargoes of Ice and as much as 40 more were shipped by other persons. . . . The business is established. It cannot be given up now and does not depend upon a single life. Mankind will have the blessing for ever whether I die soon or live long.
Tudor’s triumphant (if long-delayed) success selling ice around the world seems implausible to us today not just because it’s hard to imagine blocks of ice surviving the passage from Boston to Bombay. There’s an additional, almost philosophical, curiosity to the ice business. Most of the trade in natural goods involves material that thrives in high-energy environments. Sugarcane, coffee, tea, cotton—all these staples of eighteenth- and nineteenth-century commerce were dependent on the blistering heat of tropical and subtropical climates; the fossil fuels that now circle the planet in tankers and pipelines are simply solar energy that was captured and stored by plants millions of years ago. You could make a fortune in 1800 by taking things that grew only in high-energy environments and shipping them off to low-energy climates. But the ice trade—arguably for the only time in the history of global commerce—reversed that pattern. What made ice valuable was precisely the low-energy state of a New England winter, and the peculiar capacity of ice to store that lack of energy for long periods of time. The cash crops of the tropics caused populations to swell in climates that could be unforgivingly hot, which in turn created a market for a product that allowed you to escape the heat. In the long history of human commerce, energy had always correlated with value: the more heat, the more solar energy, the more you could grow. But in a world that was tilting toward the productive heat of sugarcane and cotton plantations, cold could be an asset as well. That was Tudor’s great insight.
—
IN THE WINTER OF 1846, Henry Thoreau watched ice cutters employed by Frederic Tudor carve blocks out of Walden Pond with a horse-drawn plow. It might have been a scene out of Brueghel, men working in a wintry landscape with simple tools, far from the industrial age that thundered elsewhere. But Thoreau knew their labor was attached to a wider network. In his diaries, he wrote a lilting reverie on the global reach of the ice trade:
Thus it appears that the sweltering inhabitants of Charleston and New Orleans, of Madras and Bombay and Calcutta, drink at my well. . . . The pure Walden water is mingled with the sacred water of the Ganges. With favoring winds it is wafted past the site of the fabulous islands of Atlantis and the Hesperides, makes the periplus of Hanno, and, floating by Ternate and Tidore and the mouth of the Persian Gulf, melts in the tropic gales of the Indian seas, and is landed in ports of which Alexander only heard the names.
If anything, Thoreau was underestimating the scope of that global network—because the ice trade that Tudor created was about much more than frozen water. The blank stares that had confronted Tudor’s first shipment of ice to Martinique slowly but steadily gave way to an ever widening dependence on ice. Ice-chilled drinks became a staple of life in southern states. (Even today, Americans are far more likely to enjoy ice with their beverages than Europeans, a distant legacy of Tudor’s ambition.) By 1850, Tudor’s success had inspired countless imitators, and more than a hundred thousand tons of Boston ice were shipped around the world in a single year. By 1860, two out of three New York homes had daily deliveries of ice. One contemporary account describes how tightly bound ice had become to the rituals of daily life:
In workshops, composing rooms, counting houses, workmen, printers, clerks club to have their daily supply of ice. Every office, nook or cranny, illuminated by a human face, is also cooled by the presence of his crystal friend. . . . It is as good as oil to the wheel. It sets the whole human machinery in pleasant action, turns the wheels of commerce, and propels the energetic business engine.
The dependence on natural ice became so severe that every decade or so an unusually warm winter would send the newspapers into a frenzy with speculation about an “ice famine.” As late as 1906, the New York Times was running alarming headlines: “Ice Up To 40 Cents And A Famine In Sight.” The paper went on to provide some historical context: “Not in sixteen years has New York faced such an iceless prospect as this year. In 1890 there was a great deal of trouble and the whole country had to be scoured for ice. Since then, however, the needs for ice have grown vastly, and a famine is a much more serious matter now than it was then.” In less than a century, ice had gone from a curiosity to a luxury to a necessity.
Ice-powered refrigeration changed the map of America, nowhere more so than in the transformation of Chicago. Chicago’s initial burst of growth had come after the nexus of canals and rail lines connected the city to both the Gulf of Mexico and the cities of the eastern seaboard. Its fortuitous location as a transportation hub—created both by nature and some of the most ambitious engineering of the century—enabled wheat to flow from the bountiful plains to the Northeast population centers. But meat couldn’t make the journey without spoiling. Chicago developed a large trade in preserved pork starting in the middle of the century, with the first stockyards slaughtering the hogs on the outskirts of the city before sending the goods east in barrels. But fresh beef remained largely a local delicacy.
But as the century progressed, a supply/demand imbalance developed between the hungry cities of the Northeast and the cattle of the Midwest. As immigration fueled the population of New York and Philadelphia and other urban centers in the 1840s and 1850s, the supply of local beef failed to keep up with the surging demand in the growing cities. Meanwhile, the conquest of the Great Plains had enabled ranchers to breed massive herds of cattle, without a corresponding population base of humans to feed. You could ship live cattle by train to the eastern states to be slaughtered locally, but transporting entire cows was expensive, and the animals were often malnourished or even injured en route. Almost half would be inedible by the time they arrived in New York or in Boston.
It was ice that ultimately provided a way around this impasse. In 1868, the pork magnate Benjamin Hutchinson built a new packing plant, featuring “cooling rooms packed with natural ice that allowed them to pack pork year-round, one of the principal innovations in the industry,” according to Donald Miller, in his history of nineteenth-century Chicago, City of the Century. It was the beginning of a revolution that would transform not only Chicago but the entire natural landscape of middle America. In the years after the fire of 1871, Hutchinson’s cooling rooms would inspire other entrepreneurs to integrate ice-cooled facilities to the meatpacking trade. A few began transporting beef back east in open-air railcars during winter, relying on the ambient temperature to keep the steaks cold. In 1878, Gustavus Franklin Swift hired an engineer to build an advanced refrigerator car, designed from the ground up to transport beef to the eastern seaboard year round. Ice was placed in bins above the meat; at stops along the route, workers could swap in new blocks of ice from above, without disturbing the meat below. “It was this application of elementary physics,” Miller writes, “that transformed the ancient trade of beef slaughtering from a local to an international business, for refrigerator cars led naturally to refrigerator ships, which carried Chicago beef to four continents.” The success of that global trade transformed the natural landscape of the American plains in ways that are still visible today: the vast, shimmering grasslands replaced by industrial feedlots, creating, in Miller’s words, “a city-country [food] system that was the most powerful environmental force in transforming the American landscape since the Ice Age glaciers began their final retreat.”
The Chicago stockyards that emerged in the last two decades of the nineteenth century were, as Upton Sinclair wrote, “the greatest aggregation of labor and capital ever gathered in one place.” Fourteen million animals were slaughtered in an average year. In many ways, the industrial food complex held in such disdain by modern-day “slow food” advocates begins with the Chicago stockyards and the web of ice-cooled transport that extended out from those grim feedlots and slaughterhouses. Progressives like Upton Sinclair painted Chicago as a kind of Dante’s Inferno of industrialization, but in reality, most of the technology employed in the stockyards would have been recognizable to a medieval butcher. The most advanced form of technology in the whole chain was the refrigerated railcar. Theodore Dreiser got it right when he described the stockyard assembly line as “a direct sloping path to death, dissection, and the refrigerator.”
The conventional story about Chicago is that it was made possible thanks to the invention of the railroad and the building of the Erie Canal. But those accounts tell only part of the story. The runaway growth of Chicago would have never been possible without the peculiar chemical properties of water: its capacity for storing and slowly releasing cold with only the slightest of human interventions. If the chemical properties of liquid water had somehow turned out to be different, life on earth would have taken a radically different shape (or more likely, would not have evolved at all). But if water hadn’t also possessed its peculiar aptitude for freezing, the trajectory of nineteenth-century America would have almost certainly been different as well. You could send spices around the globe without the advantages of refrigeration, but you couldn’t send beef. Ice made a new kind of food network imaginable. We think of Chicago as a city of broad shoulders, of railroad empires and slaughterhouses. But it is just as true to say that it was built on the tetrahedral bonds of hydrogen.
—
IF YOU WIDEN YOUR FRAME of reference, and look at the ice trade in the context of technological history, there is something puzzling, almost anachronistic, about Tudor’s innovation. This was the middle of the nineteenth century, after all, an era of coal-powered factories, with railroads and telegraph wires connecting massive cities. And yet the state of the art in cold technology was still entirely based on cutting chunks of frozen water out of a lake. Humans had been experimenting with the technology of heat for at least a hundred thousand years, since the mastery of fire—arguably Homo sapiens’ first innovation. But the opposite end of the thermal spectrum was much more challenging. A century into the industrial revolution, artificial cold was still a fantasy.
But the commercial demand for ice—all those millions of dollars flowing upstream from the tropics to the ice barons of New England—sent a signal out across the world that there was money to be made from cold, which inevitably sent some inventive minds off in search of the next logical step of artificial cold. You might assume Tudor’s success would inspire a new generation of equally mercenary entrepreneur-inventors to create the revolution in man-made refrigeration. Yet, however much we may celebrate the start-up culture of today’s tech world, essential innovations don’t always come out of private-sector exploration. New ideas are not always motivated, like Tudor’s, by dreams of “fortunes larger than we shall know what to do with.” The art of human invention has more than one muse. While the ice trade began with a young man’s dream of untold riches, the story of artificial cold began with a more urgent and humanitarian need: a doctor trying to keep his patients alive.
It’s a story that begins at the scale of insects: in Apalachicola, Florida, a town of ten thousand people living alongside a swamp in a subtropical climate—the perfect environment for breeding mosquitoes. In 1842, abundant mosquitoes meant, inevitably, the risk of malaria. At the modest local hospital, a doctor named John Gorrie sat helpless as dozens of his patients burned up with fever.
Desperate for a way to reduce his patients’ fevers, Gorrie tried suspending blocks of ice from the hospital ceiling. It turned out to be an effective solution: the ice blocks cooled the air; the air cooled the patients. With fevers reduced, some of his patients survived their illnesses. But Gorrie’s clever hack, designed to combat the dangerous effects of subtropical climates, was ultimately undermined by another by-product of the environment. The tropical humidity that made Florida such a hospitable climate for mosquitoes also helped breed another threat: hurricanes. A string of shipwrecks delayed ice shipments from Tudor’s New England, which left Gorrie without his usual supply.
Dr. John Gorrie
And so the young doctor began mulling over a more radical solution for his hospital: making his own ice. Luckily for Gorrie, it happened to be the perfect time to have this idea. For thousands of years, the idea of making artificial cold had been almost unthinkable to human civilization. We invented agriculture and cities and aqueducts and the printing press, but cold was outside the boundaries of possibility for all those years. And yet somehow artificial cold became imaginable in the middle of the nineteenth century. To use the wonderful phrase of the complexity theorist Stuart Kauffman, cold became part of the “adjacent possible” of that period.
How do we explain this breakthrough? It’s not just a matter of a solitary genius coming up with a brilliant invention because he or she is smarter than everyone else. And that’s because ideas are fundamentally networks of other ideas. We take the tools and metaphors and concepts and scientific understanding of our time, and we remix them into something new. But if you don’t have the right building blocks, you can’t make the breakthrough, however brilliant you might be. The smartest mind in the world couldn’t invent a refrigerator in the middle of the seventeenth century. It simply wasn’t part of the adjacent possible at that moment. But by 1850, the pieces had come together.
The first thing that had to happen seems almost comical to us today: we had to discover that air was actually made of something, that it wasn’t just empty space between objects. In the 1600s, amateur scientists discovered a bizarre phenomenon: the vacuum, air that seemed actually to be composed of nothing and that behaved differently from normal air. Flames would be extinguished in a vacuum; a vacuum seal was so strong that two teams of horses could not pull it apart. In 1659, the English scientist Robert Boyle had placed a bird in a jar and sucked out the air with a vacuum pump. The bird died, as Boyle suspected it might, but curiously enough, it also froze. If a vacuum was so different from normal air that it could extinguish life, that meant there must be some invisible substance that normal air was made of. And it suggested that changing the volume or pressure of gases could change their temperature. Our knowledge expanded in the eighteenth century, as the steam engine forced engineers to figure out exactly how heat and energy are converted, inventing a whole science of thermodynamics. Tools for measuring heat and weight with increased precision were developed, along with standardized scales such as Celsius and Fahrenheit, and as is so often the case in the history of science and innovation, when you have a leap forward in the accuracy of measuring something, new possibilities emerge.
All of these building blocks were circulating through Gorrie’s mind, like molecules in a gas, bouncing off each other, forming new connections. In his spare time, he started to build a refrigeration machine. It would use energy from a pump to compress air. The compression heated the air. The machine then cooled down the compressed air by running it through pipes cooled with water. When the air expanded, it pulled heat from its environment, and just like the tetrahedral bonds of hydrogen dissolving into liquid water, that heat extraction cooled the surrounding air. It could even be used to create ice.
Amazingly, Gorrie’s machine worked. No longer dependent on ice shipped from a thousand miles away, Gorrie reduced his patients’ fevers with home-grown cold. He applied for a patent—correctly predicting a future where artificial cold, as he wrote, “might better serve mankind. . . . Fruits, vegetables, and meats will be preserved in transit by my refrigeration system and thereby enjoyed by all!”
And yet, despite his success as an inventor, Gorrie went nowhere as a businessman. Thanks to Tudor’s success, natural ice was abundant and cheap when the storms didn’t disrupt trade. To make things worse, Tudor himself launched a smear campaign about Gorrie’s invention—claiming the ice produced by his machine was infected with bacteria. It was a classic case of a dominant industry disparaging a much more powerful new technology, the way the first computers with graphic interfaces were dismissed by their rivals as “toys” and not “serious business machines.” John Gorrie died penniless, having failed to sell a single machine.
But the idea of artificial cold didn’t die with Gorrie. After thousands of years of neglect, suddenly the globe lit up with patents filed for some variation of artificial refrigeration. The idea was suddenly everywhere, not because people had stolen Gorrie’s idea, but because they’d independently hit upon the same basic architecture. The conceptual building blocks were finally in place, and so the idea of creating artificially cold air was suddenly “in the air.”
Those patents rippling across the planet are an example of one of the great curiosities in the history of innovation: what scholars now call “multiple invention.” Inventions and scientific discoveries tend to come in clusters, where a handful of geographically dispersed investigators stumble independently onto the very same discovery. The isolated genius coming up with an idea that no one else could even dream of is actually the exception, not the rule. Most discoveries become imaginable at a very specific moment in history, after which point multiple people start to imagine them. The electric battery, the telegraph, the steam engine, and the digital music library were all independently invented by multiple individuals in the space of a few years. In the early 1920s, two Columbia University scholars surveyed the history of invention in a wonderful paper called “Are Inventions Inevitable?” They found 148 instances of simultaneous invention, most of them occurring within the same decade. Hundreds more have since been discovered.
Refrigeration was no different: the knowledge of thermodynamics and the basic chemistry of air, combined with the economic fortunes being made in the ice trade, made artificial cold ripe for invention. One of those simultaneous inventors was the French engineer Ferdinand Carré, who independently designed a refrigeration machine that followed the same basic principles as Gorrie’s. He built prototypes for his refrigeration machine in Paris, but his idea would ultimately triumph because of events unfolding across the Atlantic: a different kind of ice famine in the American South. After the Civil War broke out in 1861, the Union blockaded the southern states to cripple the Confederate economy. The Union navy stopped the flow of ice more effectively than did the storms that churned up along the Gulf Stream. Having built up an economic and cultural dependence on the ice trade, the sweltering southern states suddenly found themselves in desperate need of artificial cold.
As the war raged, shipments of smuggled goods could sometimes make it through the blockade at night to land at beaches along the Atlantic and Gulf coasts. But the smugglers weren’t just carrying cargoes of gunpowder or weapons. Sometimes they carried goods that were far more novel: ice-making machines, based on Carré’s design. These new devices used ammonia as a refrigerant and could churn out four hundred pounds of ice per hour. Carré’s machines were smuggled all the way from France to Georgia, Louisiana, and Texas. A network of innovators tinkered with Carré’s machines, improving their efficiency. A handful of commercial ice plants opened, marking the debut on the main stage of industrialization. By 1870, the southern states made more artificial ice than anywhere else in the world.
In the decades after the Civil War, artificial refrigeration exploded, and the natural-ice trade began its slow decline into obsolescence. Refrigeration became a huge industry, measured not just by the cash that changed hands but also in the sheer size of the machines: steam-powered monster machines weighing hundreds of tons, maintained by a full-time army of engineers. At the turn of the twentieth century, New York’s Tribeca neighborhood—now home to some of the most expensive loft apartments in the world—was essentially a giant refrigerator, entire blocks of windowless buildings designed to chill the endless flood of produce from the nearby Washington food market.
Almost everything in the nineteenth-century story of cold was about making it bigger, more ambitious. But the next revolution in artificial cold would proceed in the exact opposite direction. Cold was about to get small: those block-long Tribeca refrigerators would soon shrink down to fit in every kitchen in America. But the smaller footprint of artificial cold would, ironically, end up triggering changes in human society that were so massive you could see them from space.
—
IN THE WINTER OF 1916, an eccentric naturalist and entrepreneur moved his young family up to the remote tundra of Labrador. He had spent several winters there on his own, starting a fur company breeding foxes and occasionally shipping animals and reports back to the U.S. Biological Survey. Five weeks after the birth of his son, his wife and child joined him. Labrador was, to say the least, not an ideal place for a newborn. The climate was unforgiving, with temperatures regularly hitting 30 degrees below Fahrenheit, and the region was entirely bereft of modern medical facilities. The food, too, left a great deal to be desired. The bleak climate in Labrador meant that everything you ate during the winter was either frozen or preserved: other than the fish, there were no sources of fresh food. A typical meal would be what locals called “brewis”: salted cod and hard tack, which is rock solid bread, boiled up and garnished with “scrunchions,” which were small, fried chunks of salted pork fat. Any meat or produce that had been frozen would be mushy and tasteless when thawed out.
But the naturalist was an adventurous eater, fascinated with the cuisines of different cultures. (In his journals, he recorded eating everything from rattlesnake to skunk.) And so he took up ice fishing with some of the local Inuits, carving holes in frozen lakes and casting a line for trout. With air temperatures so far below zero, a fish pulled out of the lake would freeze solid in a matter of seconds.
Advertisement for General Electric fridge and freezer, 1949
Unwittingly, the young naturalist had stumbled across a powerful scientific experiment as he sat down to eat with his family in Labrador. When they thawed out the frozen trout from the ice-fishing expeditions, they discovered it tasted far fresher than the usual grub. The difference was so striking that he became obsessed with trying to figure out why the frozen trout retained its flavor so much more effectively. And so Clarence Birdseye began an investigation that would ultimately put his name on packages of frozen peas and fish sticks in supermarkets around the world.
At first, Birdseye had assumed the trout had preserved its freshness simply because it had been caught more recently, but the more he studied the phenomenon, he began to think there was some other factor at work. For starters, ice-fished trout would retain its flavor for months, unlike other frozen fish. He began experimenting with frozen vegetables and discovered that produce frozen in the depths of winter somehow tasted better than produce frozen in late fall or early spring. He analyzed the food under a microscope and noticed a striking difference in the ice crystals that formed during the freezing process: the frozen produce that had lost its flavor had significantly larger crystals that seemed to be breaking down the molecular structure of the food itself.
Eventually, Birdseye hit upon a coherent explanation for the dramatic difference in taste: It was all about the speed of the freezing process. A slow freeze allowed the hydrogen bonds of ice to form larger crystalline shapes. But a freeze that happened in seconds—“flash freezing,” as we now call it—generated much smaller crystals that did less damage to the food itself. The Inuit fishermen hadn’t thought about it in terms of crystals and molecules, but they had been savoring the benefits of flash freezing for centuries by pulling live fish out of the water into shockingly cold air.
Clarence Birdseye in Labrador, Canada, 1912
As his experiments continued, an idea began to form in Birdseye’s mind: with artificial refrigeration becoming increasingly commonplace, the market for frozen food could be immense, assuming you could solve the quality problem. Like Tudor before him, Birdseye began taking notes on his experiments with cold. And like Tudor, the idea would linger in his mind for a decade before it turned into something commercially viable. It was not a sudden epiphany or lightbulb moment, but something much more leisurely, an idea taking shape piece by piece over time. It was what I like to call a “slow hunch”—the anti-“lightbulb moment,” the idea that comes into focus over decades, not seconds.
The first inspiration for Birdseye had been the very pinnacle of freshness: a trout pulled out of a frozen lake. But the second would be the exact opposite: a commercial fishing ship’s hull filled with rotting cod. After his Labrador adventure, Birdseye returned to his original home in New York and took a job with the Fisheries Association, where he saw firsthand the appalling conditions that characterized the commercial fishing business. “The inefficiency and lack of sanitation in the distribution of whole fresh fish so disgusted me,” Birdseye would later write, “that I set out to develop a method that would permit the removal of inedible waste from perishable foods at production points, packaging them in compact and convenient containers, and distributing them to the housewife with their intrinsic freshness intact.”
In the first decades of the twentieth century, the frozen-food business was considered to be the very bottom of the barrel. You could buy frozen fish or produce, but it was widely assumed to be inedible. (In fact, frozen food was so appalling that it was banned at New York State prisons for being below the culinary standards of the convicts.) One key problem was that the food was being frozen at relatively high temperatures, often just a few degrees below freezing. Yet scientific advances over the preceding decades had made it possible to artificially produce temperatures that were positively Labradorian. By the early 1920s, Birdseye had developed a flash-freezing process using stacked cartons of fish frozen at minus 40 degrees Fahrenheit. Inspired by the new industrial model of Henry Ford’s Model T factory, he created a “double-belt freezer” that ran the freezing process along a more efficient production line. He formed a company called General Seafood using these new production techniques. Birdseye found that just about anything he froze with this method—fruit, meat, vegetables—would be remarkably fresh after thawing.
Frozen food was still more than a decade away from becoming a staple of the American diet. (It required a critical mass of freezers—in supermarkets and home kitchens—that wouldn’t fully come into being until the postwar years.) But Birdseye’s experiments were so promising that in 1929, just months before the Black Friday crash, General Seafood was acquired by the Postum Cereal Company, which promptly changed its name to General Foods. Birdseye’s adventures in ice fishing had made him a multimillionaire. His name endures on packages of frozen fish filets to this day.
Birdseye’s frozen-food breakthrough took shape as a slow hunch, but it also emerged as a kind of collision between several very different geographic and intellectual spaces. To imagine a world of flash-frozen food, Birdseye needed to experience the challenges of feeding a family in an arctic climate surrounded by brutal cold; he needed to spend time with the Inuit fishermen; he needed to inspect the foul containers of cod-fishing trawlers in New York harbors; he needed the scientific knowledge of how to produce temperatures well below freezing; he needed the industrial knowledge of how to build a production line. Like every big idea, Birdseye’s breakthrough was not a single insight, but a network of other ideas, packaged together in a new configuration. What made Birdseye’s idea so powerful was not simply his individual genius, but the diversity of places and forms of expertise that he brought together.
Worker clad in overalls surveys boxes of Birds Eye frozen foods as they move along a conveyor. Undated photograph, circa 1922–1950.
In our age of locally sourced, artisanal food production, the frozen “TV dinners” that arose in the decades after Birdseye’s discovery have fallen out of favor. But in its original incarnation, frozen food had a positive impact on health, introducing more nutrition into the diets of Americans. Flash-frozen food extended the reach of the food network in both time and space: produce harvested in summer could be consumed months later; fish caught in the North Atlantic could be eaten in Denver or Dallas. It was better to eat frozen peas in January than it was to wait five months for fresh ones.
—
BY THE 1950S, Americans had adopted a lifestyle that was profoundly shaped by artificial cold, buying frozen dinners purchased in the refrigerated aisles of the local supermarket, and stacking them up in the deep freeze of their new Frigidaires, featuring the latest in ice-making technology. Behind the scenes, the entire economy of cold was supported by a vast fleet of refrigerated trucks, transporting Birds Eye frozen peas (and their many imitations) around the country.
In that iconic 1950s American household, the most novel cold-producing device was not storing fish filets for dinner or making ice for the martinis. It was cooling down (and dehumidifying) the entire house. The first “apparatus for treating air” had been dreamed up by a young engineer named Willis Carrier in 1902. The story of Carrier’s invention is a classic in the annals of accidental discovery. As a twenty-five-year-old engineer, Carrier had been hired by a printing company in Brooklyn to devise a scheme that would help them keep the ink from smearing in the humid summer months. Carrier’s invention not only removed the humidity from the printing room; it also chilled the air. Carrier noticed that everyone suddenly wanted to have lunch next to the printing presses, and he began to design contraptions that would be deliberately built to regulate the humidity and temperature in an interior space. Within a few years, Carrier had formed a company—still one of the largest air-conditioning manufacturers in the world—that focused on industrial uses for the technology. But Carrier was convinced that air-conditioning should also belong to the masses.
A Carrier Corporation experimental lab test of their new $700, six-room capacity, central air-conditioning unit that diffuses cool air at floor level; smoke making cool air visible has risen to the three-foot-high level in this living room, 1945.
His first great test came over Memorial Day weekend of 1925, when Carrier debuted an experimental AC system in Paramount Pictures’ new flagship Manhattan movie theater, the Rivoli. Theaters had long been oppressive places to visit during the summer months. (In fact, a number of Manhattan playhouses had experimented with ice-based cooling during the nineteenth century, with predictably moist results.) Before AC, the whole idea of a summer blockbuster would have seemed preposterous: the last place you’d want to be on a warm day was a room filled with a thousand other perspiring bodies. And so Carrier had persuaded Adolph Zukor, the legendary chief of Paramount, that there was money to be made by investing in central air for his theaters.
Sackett & Wilhelms printing company air-conditioning system
Zukor himself showed up for the Memorial Day weekend test, sitting inconspicuously in the balcony seats. Carrier and his team had some technical difficulties getting the AC up and running; the room was filled with hand fans waving furiously before the picture started. Carrier later recalled the scene in his memoirs:
It takes time to pull down the temperature in a quickly filled theater on a hot day, and a still longer time for a packed house. Gradually, almost imperceptibly, the fans dropped into laps as the effects of the air conditioning system became evident. Only a few chronic fanners persisted, but soon they, too, ceased fanning. . . . We then went into the lobby and waited for Mr. Zukor to come downstairs. When he saw us, he did not wait for us to ask his opinion. He said tersely, “Yes, the people are going to like it.”
—
BETWEEN 1925 AND 1950, most Americans experienced air-conditioning only in large commercial spaces such as movie theaters, department stores, hotels, or office buildings. Carrier knew that AC was headed for the domestic sphere, but the machines were simply too large and expensive for a middle-class home. The Carrier Corporation did offer a glimpse of this future in its 1939 World’s Fair attraction, “The Igloo of Tomorrow.” In a bizarre structure that looked something like a five-story helping of soft-serve vanilla ice cream, Carrier showcased the wonders of domestic air-conditioning, accompanied by a squadron of Rockettes-style “snow bunnies.”
But Carrier’s vision of domestic cool would be postponed by the outbreak of World War II. It wasn’t until the late 1940s, after almost fifty years of experimentation, that air-conditioning finally made its way to the home front, with the first in-window portable units appearing on the market. Within half a decade, Americans were installing more than a million units a year. When we think about twentieth-century miniaturization, our minds naturally gravitate to the transistor or the microchip, but the shrinking footprint of air-conditioning deserves its place in the annals of innovation as well: a machine that had once been larger than a flatbed truck reduced in size so that it could fit in a window.
That shrinking would quickly set off an extraordinary chain of events, in many ways rivaling the impact of the automobile on settlement patterns in the United States. Places that had been intolerably hot and humid—including some of the cities where Frederic Tudor had sweated out the summer as a young man—were suddenly tolerable to a much larger slice of the general public. By 1964, the historic flow of people from South to North that had characterized the post–Civil War era had been reversed. The Sun Belt expanded with new immigrants from colder states, who could put up with the tropical humidity or blazing desert climates thanks to domestic air-conditioning. Tucson rocketed from 45,000 people to 210,000 in just ten years; Houston expanded from 600,000 to 940,000 in the same decade. In the 1920s, when Willis Carrier was first demonstrating air-conditioning to Adolph Zukor at the Rivoli Theatre, Florida’s population stood at less than one million. Half a century later, the state was well on the way to becoming one of the four most populous in the country, with ten million people escaping the humid summer months in air-conditioned homes. Carrier’s invention circulated more than just molecules of oxygen and water. It ended up circulating people as well.
Broad changes in demography invariably have political effects. The migration to the Sun Belt changed the political map of America. Once a Democratic stronghold, the South was besieged by a massive influx of retirees who were more conservative in their political outlook. As the historian Nelson W. Polsby demonstrates in his book How Congress Evolves, Northern Republicans moving south in the post-AC era did as much to undo the “Dixiecrat” base as the rebellion against the civil rights movement. In Congress, this had the paradoxical effect of unleashing a wave of liberal reforms, as the congressional Democrats were no longer divided between conservative Southerners and progressives in the North. But air-conditioning arguably had the most significant impact on Presidential politics. Swelling populations in Florida, Texas, and Southern California shifted the electoral college toward the Sun Belt, with warm-climate states gaining twenty-nine electoral college votes between 1940 and 1980, while the colder states of the Northeast and Rust Belt lost thirty-one. In the first half of the twentieth century, only two presidents or vice presidents hailed from Sun Belt states. Starting in 1952, however, every single winning presidential ticket contained a Sun Belt candidate, until Barack Obama and Joe Biden broke the streak in 2008.
This is long-zoom history: almost a century after Willis Carrier began thinking about keeping the ink from smearing in Brooklyn, our ability to manipulate tiny molecules of air and moisture helped transform the geography of American politics. But the rise of the Sun Belt in the United States was just a dress rehearsal for what is now happening on a planetary scale. All around the world, the fastest growing megacities are predominantly in tropical climates: Chennai, Bangkok, Manila, Jakarta, Karachi, Lagos, Dubai, Rio de Janeiro. Demographers predict that these hot cities will have more than a billion new residents by 2025.
It goes without saying that many of these new immigrants don’t have air-conditioning in their homes, at least not yet, and it is an open question whether these cities are sustainable in the long run, particularly those based in desert climates. But the ability to control temperature and humidity in office buildings, stores, and wealthier homes allowed these urban centers to attract an economic base that has catapulted them to megacity status. It’s no accident that the world’s largest cities—London, Paris, New York, Tokyo—were almost exclusively in temperate climates until the second half of the twentieth century. What we are seeing now is arguably the largest mass migration in human history, and the first to be triggered by a home appliance.
—
THE DREAMERS AND INVENTORS who ushered in the cold revolution didn’t have eureka moments, and their brilliant ideas rarely transformed the world immediately. Mostly they had hunches, but they were tenacious enough to keep those hunches alive for years, even decades, until the pieces came together. Some of those innovations can seem trivial to us today. All that collective ingenuity, focused over decades and decades—all to make the world safe for the TV dinner? But the frozen world that Tudor and Birdseye helped conjure into being would do more than just populate the world with fish sticks. It would also populate the world with people, thanks to the flash freezing and cryopreservation of human semen, eggs, and embryos. Millions of human beings around the world owe their existence to the technologies of artificial cold. Today, new techniques in oocyte cryopreservation are allowing women to store healthy eggs in their younger years, extending their fertility well into their forties and fifties in many cases. So much of the new freedom in the way we have children now—from lesbian couples or single mothers using sperm banks to conceive, to women giving themselves two decades in the workforce before thinking about kids—would have been impossible without the invention of flash freezing.
When we think about breakthrough ideas, we tend to be constrained by the scale of the original invention. We figure out a way to make artificial cold, and we assume that will just mean that our rooms will be cooler, we’ll sleep better on hot nights, or there will be a reliable supply of ice cubes for our sodas. That much is easy to understand. But if you tell the story of cold only in that way, you miss the epic scope of it. Just two centuries after Frederic Tudor started thinking about shipping ice to Savannah, our mastery of cold is helping to reorganize settlement patterns all over the planet and bring millions of new babies into the world. Ice seems at first glance like a trivial advance: a luxury item, not a necessity. Yet over the past two centuries its impact has been staggering, when you look at it from the long-zoom perspective: from the transformed landscape of the Great Plains; to the new lives and lifestyles brought into being via frozen embryos; all the way to vast cities blooming in the desert.