Absolute Zero and the Conquest of Cold (10 page)

A real chameleon of a gas, a pungent compound of nitrogen and hydrogen, at one moment ammonia could exist in the liquid compound "ammonia water," and at the next—when the ammonia water was heated—ammonia would separate from the water and become a gas; and that gas could also be subjected to pressure and turned into a different liquid, a liquefied gas. In 1823 Faraday examined all of these states, and in the process, he demonstrated that liquefied ammonia could be used to generate cold.

To understand why, and how, it is necessary to repeat, in print, an ice experiment that many scientists were performing for themselves and their students in laboratories all over Europe in the first quarter of the nineteenth century. Its point was to show how ice cools things—not, as most people believed, by conduction alone, by conveying its own coldness to neighboring materials—but mostly by melting, during which ice absorbs heat from its surroundings. Scientists first mixed a pound of water at the boiling point, 212°F, with a pound of water at 34°F; the result was 2 pounds of water at 123°F, a midpoint that could be mathematically expected. But then they mixed a pound of water at 212°F with a pound of
ice
at 32°F and obtained a startlingly different result—2 pounds of water at 51°F. An amount of heat that would have been sufficient to raise 2 pounds of water another 72°F had been absorbed by the change from solid ice to liquid water. Faraday recognized that what made ammonia change rapidly from its liquefied to its gaseous state was a similar absorption of heat from the surroundings—and that this was what lowered temperature and produced cold.

Faraday noted that "there is great reason to believe that [this technique] may be successfully employed for the preservation of animal and vegetable substances for the purposes of food," but he did nothing personally to advance the commercial possibilities of generating cold by means of ammonia's absorptive capacities. The reasons for this inaction are not described in his notebooks or diaries, but he was known to be a determinedly uncommercial man, a member of a Quaker-like religious sect devoted to giving up worldly things to better elucidate the works of God. During the first flush of the Industrial Revolution, Faraday turned down repeated requests from entrepreneurs to act as a paid consultant to their endeavors in other fields, and surely he would not have considered setting up a refrigeration business or licensing his process to others to do so.

Simultaneously with Faraday's experiments, in 1823 in Paris another, more obscure experimenter was working. An École Polytechnique graduate, Charles Cagniard de la Tour, was attempting to do the opposite of what Faraday was doing: turn a liquid into a gas. By using heat and pressure, Cagniard de la Tour succeeded in pushing pure alcohol to the point where it completely became a gas. By 1832 he had done enough work to reach the important conclusion that each liquid has a "critical temperature" above which it must pass into a gaseous state. This conclusion also meant the obverse was true: a temperature existed below which every gas must become a liquid.

The chemist Charles Saint-Ange Thilorier followed up on the work of Cagniard de la Tour. In the laboratory of the School of Pharmacy, in Paris, in 1834, Thilorier accomplished what other researchers had tried but failed to do: he pressured gaseous carbon dioxide until it became a solid, carbonic acid, which afterward was known as "dry ice." The accomplishment did not come cheaply: one experiment resulted in an explosion in which Thilorier's assistant lost both legs. Dry ice would eventually come to be a major component of refrigeration systems. But though Thilorier was working in a school of pharmacy, he evidently thought no more about commercial possibilities than Faraday had. What he did do with solid carbonic acid was stir it into a mixture of snow and ether, and thereby reach a temperature of—no°C, the lowest ever recorded at that time.

By a single technological leap, a far interior outpost of the country of the cold had been gained. Minus no°C was about as far below the freezing point of water as the boiling point of water, plus 100°C, was above it. Moreover,—no°C was a temperature that had not previously been proved to exist, though scientists had understood from Amontons that such a low temperature was possible, and it existed nowhere else on Earth except in this Parisian laboratory. Despite that, the Thilorier work did not excite much attention among other scientists, and it languished for lack of interest, as did other scientific work equally important to the history of cold, also done in Paris in that era, by the theoretician Sadi Carnot, as will be recounted in the next chapter.

Back in the American Northeast, in the mid-1820s, Frederic Tudor recovered from his mental breakdown and made two important alterations to his personal and business life. He married, and he had the good sense to hire young Nathaniel Jarvis Wyeth. The two men shared an aversion to college and a predilection for intellectual companions—editors and publishers. Wyeth was not a theoretical scientist, or a scientific experimentalist, or an instrument maker/technologist whose work was based on advances in scientific understandings. He was a pure tinkerer whose 1825 device for harvesting ice revolutionized the industry. A saw-toothed cutter designed for a horse to pull, it scored the ice so deeply and neatly that the ice could then be readily split into blocks and floated downstream to an icehouse. The ice cutter slashed the cost of harvesting ice from 30 cents a ton to 10 cents; also, because it produced extremely regular blocks, it made shippers more eager to carry these blocks than they had been to transport the irregularly shaped blocks and chips of old, which could shift about dangerously in a hold. Tudor first contracted with Wyeth to supply ice, then, recognizing Wyeth's worth, employed him directly. Tudor was soon confiding to his Ice-House Diary that on a visit to his ice-harvesting site, he had been pleased to chance upon his new employee "wandering about the woods at Fresh Pond in all the lonely perturbations of invention and contrivance. His mind evidently occupied in improving the several contrivances which he is perfecting for carrying into good effect improvements in his several machines for the ice business."

Among those advances was the determination of the best insulation between blocks of ice. Wyeth fastened on a ubiquitous substance whose use for this purpose had eluded everyone else: sawdust, from the hundreds of sawmills throughout New England. With this innovation, and Wyeth's series of technological advances—an endless chain to lift blocks from the river channel, an auger to drill through fields of ice and drain water on top, new tongs, new tools—Tudor's enterprise shot ahead rapidly, and by the early 1830s he almost monopolized the ice trade in the United States.

Tudor doubled Wyeth's salary, to $1,200 a year, but did no more for the younger man, even as the business expanded so much that Tudor became known as the Ice King. Wyeth wanted to go out on his own but lacked the capital to start an ice-trade enterprise. The two men struck a deal: Tudor paid Wyeth $2,500, and in exchange obtained Wyeth's patent on his ice-harvesting process. Wyeth then left for Oregon, expecting to procure furs and salmon to sell in the East. His trip ended in frustration, but his work was so audacious and his reports of it in the journals he kept were so vivid that Washington Irving eventually turned them into a popular book,
The Adventures of Captain Bonneville.
Tudor discovered that having the patent without the inventor did no good, since rival ice producers used Wyeth's methods without payment to Tudor, and since in the absence of an inventive second-in-command, Tudor was unable to prevent the rivals from cutting into his business in the South. Tudor also exacerbated his losses through an ill-conceived venture in coffee trading, in which more than $150,000 vanished.

Broke again, Tudor escaped jail after promising to continue in business and repay every cent he owed, plus interest. Wyeth came back from Oregon and toiled again for Tudor, but then the two men locked horns in an acrimonious court dispute over the rights that had been conveyed in the patent sale, and they became rivals. Wyeth helped charter a railroad line from the ice ponds to the Boston docks, and he introduced steam power to the harvesting, warehousing, and transport of ice, reaping from these efforts a good but not enormous income. At the same time, Tudor's emissaries successfully ventured to India, other parts of southern Asia, Australia, and South America. Henry Thoreau watched Tudor's cutters working on Walden Pond and marveled that water from his bathing beach was traveling halfway around the globe to become the beverage of East Indian philosophers. In 1849 a Scottish journal, citing the successful delivery of ice to Calcutta, suggested, "If means could be contrived for transporting fresh meat in ice at small cost, Europe would present a steady market for the surplus beef and mutton of America." By the outset of the Civil War, Tudor, Wyeth, and their competitors were shipping the equivalent of one cargo each day, every day of the year, to more than fifty ports. Tudor repaid what he owed and became a multimillionaire, principally responsible for an annual ice harvest in the Northeast measured in the hundreds of thousands of tons.

Richard O. Cummings points out in the definitive study of the American ice trade that Tudor made more money in the latter part of his career under conditions of competition than he did when he had a virtual monopoly on natural ice. The reason for Tudor's rise in wealth was the vastly enlarged dollar volume of the ice trade itself.

Most of the ice used in the world was consumed in the United States. Starting in the 1820s, ice consumption more than doubled each year as Americans grew used to having ice to cool drinks and to keep food fresh in larders. When various innovations permitted Tudor, Wyeth, and their rivals to reduce the retail price to 12/2 cents for 100 pounds—a far cry from the $6 per 100 pounds that ice had once cost—its cheapness spurred further innovation in food use, which in turn led to even greater demand for ice. One of the new concoctions was to become a totem of the South, the mint julep, and it is entirely likely that the first of these alcohol-laden drinks, in the 1820s, was made with ice from that totemic site of the Northeast, Walden Pond. Shortly, many southerners sought ice for making juleps. Temperance societies also liked and touted ice, believing it promoted the use of a more healthful beverage, cold water. Ice consumption in New Orleans rose from 375 tons in 1827 to 24,000 tons in 1860; and during the same period, New York City raised its annual consumption of ice to 100,000 tons.

The diets of urban Americans underwent a marked change starting in the 1830s, a change intertwined with the increased use of ice. Fresh, unpreserved fruits, vegetables, meats, and milk rose in popularity. Upstate New York farmers began using ice to refrigerate their milk, so it could be taken by railroad to New York City, a trip of more than four and a half hours. Fresh seafood was iced and transported from port cities to cities 200 to 300 miles inland. Ice also prolonged the period of the year when meat could be cured, providing the steady low temperatures necessary to preserve meat with salt or smoke before it began to spoil.

Rapidly enlarging American cities also contributed to the growth of refrigeration in two further ways. An expanding urban population that could not grow its own food needed refrigeration to preserve its supplies; and with fewer people left in the rural areas to harvest the fields and transport the products quickly, ever more refrigeration was needed to store food until ready for market.

Most refrigeration occurred in the country's North and Midwest. The relative dearth of it in the South, because of the absence of natural-ice sources and the expense of importing ice, affected the character of farming in the region. While the northern areas developed dairy, vegetable, and meat farms, the southern farms, with less access to and facilities for refrigeration, tended to stick with cotton and tobacco, crops that could be grown, harvested, stored, and transported to market without temperature controls.

Refrigerators that used stored ice were only partly effective, because refrigerator makers did not yet understand the way that ice cools. They did not comprehend that ice does not cool by conduction but by absorbing heat from the surroundings. Lacking that knowledge, early refrigerator makers like Moore constructed their devices to preserve ice and preclude it from melting by cutting off the airflow, an action that prevented the ice from cooling by absorption. Not until 1845 did inventors begin to produce icebox refrigerators that circulated air and therefore worked better than the older ones.

Another spur to American demand for refrigeration was the introduction of lager beer. Before lager arrived from Germany, American beers were made by "top-fermenting," a process that took place at the surface of the liquid and could occur at any temperature. Lager beer was created through the action of yeast, in a bottom-fermenting process that resulted in a mix that then had to be stored at between 47° and 55°F so it could mellow, develop carbon dioxide fizz, and become an aged beer. Ice could ensure the maintenance of the desired temperature and also permit the manufacture of lager beer year-round, instead of only in winter. The arrival of significant numbers of German immigrants to the United States in the 1840s accelerated the demand for lager beer and for ice to produce it. By the 1860s, American brewers were buying $1 million worth of ice each year.

"Ice is an American institution—the use of it an American luxury—the abuse of it an American failing,"
De Bow's Review
asserted in 1855, contrasting the American use of ice for household refrigeration with that of Europe, where ice was "confined to the wine cellars of the rich, and the cooling pantries of first class confectionaries." Ice helped point the American dream in the direction of material comfort for the masses. And ice became a symbol of America: when a competitor of Tudor's broke into the London market, he mounted a specimen of his ice, taken from Lake Wenham in Massachusetts, in the window of his London store, replacing it each day so that to passersby the ice appeared crystalline perfect, never melting, always the same. Shortly, Wenham ice became synonymous with purity and was greatly desirable—the empress Anna's jewel of an ice palace, made accessible to the masses by the power of American democracy and unfettered capitalism.