by Tom Standage
At the beginning of the seventeenth century potatoes were widely regarded as suitable fodder for animals, but to be eaten by humans only as a last resort, when no other food was available. The potato made slow progress in the following years, being consumed only by the very rich (it was prized by some aristocratic gardeners and was served as a novelty) and the very poor (it became a staple food among the poor, first in Ireland, and then in parts of En gland, France, the Low Countries, the Rhineland, and Prussia). Famines brought the potato new converts, as people who had no choice but to eat potatoes soon discovered that they were not so terrible after all. One of the first acts of the Royal Society, Britain’s pioneering scientific society, after its foundation in 1660, was to point out the value of potatoes in times of famine—on the basis that in years when the wheat crop failed, there was often a good potato harvest. But this advice was ignored, and it was only when famine struck, as it did in France in 1709, that the virtues of potatoes were made starkly clear and the threat of starvation forced people to put aside their prejudices.
A series of famines in the eighteenth century earned the potato some friends in high places. When the crops failed in 1740, Frederick the Great of Prussia urged wider cultivation of potatoes among his subjects. His government distributed a handbook explaining how to grow the new crop and distributed free seed potatoes. Other European governments did the same, making promotion of the potato official policy. In Russia, Catherine the Great’s medical advisers convinced her that the potato could be an antidote to starvation; governments in Bohemia and Hungary also advocated its cultivation. Sometimes potato advocacy was backed by force: Austrian peasants were threatened with forty lashes if they refused to embrace it. Warfare also helped to change attitudes. During their campaigns in northern Europe in the 1670s and 1680s, Louis XIV’s armies encountered potatoes in Flanders and the Rhineland, where they were being grown in some quantity by this time. One observer noted that “the French Army found great support thereby by feeding the common Soldiers most plenteously; it is both delicious and wholesome.”
Austrian, French, and Russian soldiers who fought in Prussia during the Seven Years’ War (1756–63) saw how potatoes (planted at Frederick the Great’s urging) sustained the local population, and they advocated their cultivation when they returned home. One advantage of the potato during war time was that it remained hidden safely underground; even if an army camped on a field of potatoes, the farmer could still harvest them afterward.
One man’s experience of potatoes during the Seven Years’ War inspired him to become the potato’s greatest champion. Antoine-Augustin Parmentier, a French scientist, served as a pharmacist in the French army. After being captured by the Prussians he spent three years in prison, and for much of that time he was given nothing more than potatoes to eat. He concluded that they were a nourishing and healthy food, and when the war ended and he returned to France he became a vocal potato advocate. After yet another poor harvest in 1770, when a prize was offered for the best essay on “foodstuffs capable of reducing the calamities of famine,” Parmentier won with a eulogy to the potato. Even though potatoes were still widely believed to be poisonous and to cause disease, he won backing for his views in 1771 from the medical faculty at the Sorbonne university in Paris, which ruled that the potato was indeed fit for human consumption. Shortly afterward Parmentier published a detailed scientific analysis of the merits of the potato. But support among the scientific community was one thing; after years of effort, Parmentier found that convincing people to cultivate and eat potatoes was quite another.
So he organized a series of publicity stunts. In 1785, at a banquet to celebrate the birthday of Louis XVI, Parmentier presented the king and queen with a bouquet of potato flowers, whereupon the king pinned one of the flowers to his lapel, and Marie-Antoinette put a garland in her hair. When the guests sat down to eat, several of the dishes included potatoes. With the endorsement of the king and queen, eating potatoes and wearing potato flowers soon became fashionable among the aristocracy. Parmentier also hosted several dinners of his own, serving potatoes prepared in a variety of ways to emphasize their versatility. (The American statesman and scientist Benjamin Franklin was among the celebrities invited to these dinners.) But Parmentier’s greatest trick was to post armed guards around the fields just outside Paris, given to him by the king, where he was growing potatoes. This aroused the interest of the local people, who wondered what valuable crop could possibly require such security measures. Once the crop was ready, Parmentier ordered the guards to withdraw, and the locals duly rushed in and stole the potatoes. As hostility toward the potato finally crumbled, the king is said to have told Parmentier: “France will thank you some day for having found bread for the poor.” But it was only some years later, after the French Revolution (during which Louis XVI and Marie-Antoinette were guillotined), that the king’s prediction proved correct. In 1802 Napoleon Bonaparte instituted the order of the Legion d’Honneur, and Parmentier was among its first recipients. His service to the potato is remembered today in the form of several potato-based dishes that bear his name.
It was a similar if less poetic story elsewhere in Eu rope: The combination of famine, war, and government promotion meant that by 1800, the potato had established itself as an important new foodstuff. Sir Frederick Eden, an English writer and social researcher, wrote that in Lancashire “it is a constant standing dish, at every meal, breakfast excepted, at the tables of the Rich, as well as the Poor . . . potatoes are perhaps as strong an instance of the extension of human enjoyment as can be mentioned.” The potato was hailed as “the greatest blessing that the soil produces,” “the miracle of agriculture,” and “that most valuable of roots.” After bad wheat harvests in 1793 and 1794, many people dropped their opposition to potatoes in 1795. That year the Times of London even printed recipes for potato soup and for bread with maize and potatoes. One factor that counted in the potato’s favor was the high status of white bread, made from wheat, compared with brown bread, made from rye, oats, and barley. English workers who had become wealthy enough to switch from brown to white bread during the eighteenth century were very reluctant to switch back again. When times were hard, they would sooner eat potatoes.
In his book The Wealth of Nations, published in 1776, the Scottish philosopher and economist Adam Smith observed that “the food produced by a field of potatoes is not inferior in quantity to that produced by a field of rice, and much superior to what is produced by a field of wheat.” Even allowing for the fact that potatoes contained a large amount of water, he noted, “an acre of potatoes will still produce six thousand weight of solid nourishment, three times the quantity produced by the acre of wheat.” His praise of the potato continued with words that now seem prophetic: “Should this root ever become in any part of Europe, like rice in some rice countries, the common and favorite vegetable food of the people, so as to occupy the same proportion of the lands in tillage which wheat and other sorts of grain for human food do at present, the same quantity of cultivated land would maintain a much greater number of people, and . . . population would increase.”
FROM COLUNBUS TO MALTHUS
Three centuries after Columbus’s arrival in the Americas, the ensuing exchange of plants, diseases, and people had transformed the world’s population and its distribution. Smallpox, chicken pox, influenza, typhus, measles, and other Old World diseases—many of them consequences of human proximity to domesticated animals such as pigs, cows, and chickens that had been unknown in the New World—had decimated the native peoples of the Americas, who lacked immunity to such diseases, paving the way for European conquest. Estimates of the size of the pre-Columbian population of the Americas vary from 9 million to 112 million, but a consensus figure of 50 million, which had been reduced by disease and warfare to some 8 million by 1650, gives an idea of the scale of the destruction. Even as their invisible biological allies wiped out the indigenous peoples of the Americas, Europeans began importing slaves from Africa on a v
ast scale to work on sugar plantations. The demographics of Africa and the Americas were transformed. But the Columbian Exchange also helped to alter the demographics of Eurasia.
In China, the arrival of maize and sweet potatoes contributed to the increase in population from 140 million in 1650 to 400 million in 1850. Since maize could be grown in areas that were too dry for rice, and on hillsides that could not be irrigated, it added to the food supply and allowed people to live in new places. The uplands of the Yangtze basin were deforested to make way for the production of indigo and jute, for example, and the peasants who grew them lived on maize and sweet potatoes, which grew well in the hills. Another practice that allowed food production to keep pace with a growing population was that of multiple cropping. When rice is grown in paddies, it absorbs most of its nutrients from water rather than soil, so it can be repeatedly cropped on the same land without the need to leave the land fallow to allow the soil to recover. Farmers in southern China could sometimes produce two or even three crops a year from a single plot of land.
In Europe, meanwhile, the new crops played a part in enabling the population to grow from 103 million in 1650 to 274 million in 1850. During the sixteenth century, Europe’s staple crops, wheat and rye, produced about half as much food per hectare (measured by weight) as maize did in the Americas, and about a quarter as much as rice did in southern Asia. So the arrival of maize and potatoes in Europe provided a way to produce much more food from the same amount of land. The most striking example was that of Ireland, where the population increased from around 500,000 in 1660 to 9 million in 1840—something that would not have been possible without the potato. Without it, the whole country could only have produced enough wheat to support 5 million people. Potatoes meant that there was enough food to support nearly twice this number, even as wheat continued to be grown for export. Potatoes could be grown on European land that was unsuitable for wheat, and were far more reliable. Being better fed made people healthier and more resistant to disease, causing the death rate to fall and the birth rate to rise. And what potatoes did in the north of Europe, maize did in the south: the populations of Spain and Italy almost doubled during the eighteenth century.
As well as adopting the new crops, European farmers increased production by bringing more land under cultivation and developing new agricultural techniques. In particular, they introduced crop rotations involving clover and turnips (most famously, in Britain, the “Norfolk four-course rotation” of turnips, barley, clover, and wheat). Turnips were grown on land that would otherwise have been left fallow, and then fed to animals, whose manure enhanced the barley yields the following year. Feeding animals with turnips also meant that land used for pasture could instead be used to grow crops for human consumption. Similarly, growing clover helped to restore the fertility of the soil to ensure a good wheat harvest in the following year. Another innovation was the adoption of the seed drill, a horse-drawn device which placed seeds into holes in the soil at a precise depth. Sowing seeds in this way, rather than scattering them in the traditional manner, meant that crops were properly spaced in neat rows, making weeding easier and ensuring that adjacent plants did not compete for nutrients. Again, this helped to increase the yields of cereal crops.
By the end of the eighteenth century, however, there were signs that the European surge in agricultural productivity could no longer keep up with population growth. The problem was most noticeable in En gland, which had been more successful than other European countries in increasing its food production, and so had more difficulty maintaining the pace it had set itself once the population expanded. During the first half of the century, England had exported grain to continental Europe; but after 1750 the growing population, and a succession of bad harvests, led to shortages and higher prices. Agricultural output was still growing (by around 0.5 percent a year), but only at about half the rate of population growth (around 1 percent a year), so the amount of food per head was falling. The same thing was happening across Europe: anthropometric research shows that European adults born between 1770 and 1820 were, on average, noticeably shorter than previous generations had been.
In China, rice production could be increased using more labor and more multiple cropping. But that was not an option for Europe-an crops, so the obvious thing to do was to bring even more land under cultivation. The problem was that the supply of land was finite, and it was needed for other things besides agriculture: to grow wood for construction and fuel, and to accommodate Europe’s growing cities. Again, the problem was particularly acute in England, where urbanization had been most rapid. People began to worry that the population would soon outstrip the food supply. The problem was elegantly summarized by the English economist Thomas Malthus, who published An Essay on the Principle of Population in 1798. It was an extraordinarily influential work, and its main argument runs as follows:
The power of population is indefinitely greater than the power in the earth to produce subsistence for man. Population, when unchecked, increases in a geometrical ratio. Subsistence increases only in an arithmetical ratio. A slight acquaintance with numbers will shew the immensity of the first power in comparison of the second. By that law of our nature which makes food necessary to the life of man, the effects of these two unequal powers must be kept equal. This implies a strong and constantly operating check on population from the difficulty of subsistence. This difficulty must fall somewhere and must necessarily be severely felt by a large portion of mankind.
Malthus thought that this predicament, which is now known as a “Malthusian trap,” was inescapable. Given the chance, the population would double every twenty-five years or so, and then double again after the same interval, increasing in a geometric ratio; and despite the rapid increase in agricultural productivity of the preceding decades it was difficult to see how food production could possibly keep up. Even if food production could somehow be doubled from its level in the 1790s, that would only buy another twenty-five years’ breathing space; it was hard to imagine how it could be doubled again. “During the next period of doubling, where will the food be found to satisfy the importunate demands of the increasing numbers?” Malthus asked. “Where is the fresh land to turn up?” Rapid population growth had, Malthus noted, been possible in the North American colonies, but that was because the population was relatively small in relation to the abundant land available.
“I see no way by which man can escape from the weight of this law which pervades all animated nature,” he gloomily concluded. “No fancied equality, no agrarian regulations in their utmost extent, could remove the pressure of it even for a single century. And it appears, therefore, to be decisive against the possible existence of a society, all the members of which should live in ease, happiness, and comparative leisure; and feel no anxiety about providing the means of subsistence for themselves and families.” He anticipated a future of food shortages, starvation, and misery. The potato, Malthus believed, was partly to blame. Having been championed as a remedy for starvation, it now seemed to be hastening the onset of an apparently inevitable crisis. And even if it provided enough food to go around, Malthus argued, the potato caused the population to increase far beyond the opportunities for employment. With hindsight, of course, we can appreciate the irony that Malthus pointed out the biological constraints on population and economic growth just at the moment when Britain was about to demonstrate, for the first time in human history, that they no longer applied.
8
THE STEAM ENGINE AND THE POTATO
It is the fashion to extol potatoes, and to eat potatoes. Every one joins in extolling potatoes, and all the world like potatoes, or pretend to like them, which is the same thing in effect.
—WILLIAM COBBETT, English FARMER AND PAMPHLETEER, 1818
“THE OFFSPRING OF AGRICULTURE”
From the dawn of prehistory to the beginning of the nineteenth century, almost all of the necessities of life had been provided by things that grew on the land. The land supplied food crops of
various kinds; wood for fuel and construction; fibers with which to make clothing; and fodder for animals, which in turn provided more food, along with other useful materials such as wool and leather. Butchers, bakers, shoemakers, weavers, carpenters, and shipbuilders depended on animal or vegetable raw materials, all of which were the products, directly or indirectly, of photosynthesis—the capture of the sun’s energy by growing plants. Since all these things came from the land, and since the supply of land was limited, Thomas Malthus concluded that there was an ecological limit that growing populations and economies would eventually run into. He first made this prediction on the eve of the nineteenth century, and he refined his argument in the following years.
Yet Britain did not hit the ecological wall that Malthus anticipated. Instead, it vaulted over it and broke free of the constraints of the “biological old regime” in which everything was derived from the produce of the land. Rather than growing most of its own food, Britain concentrated on manfacturing industrial goods, notably cotton textiles, which could then be traded for food from overseas. During the nineteenth century the population more than tripled, but the economy grew faster still, so that the average standard of living increased—an outcome that would have astonished Malthus. Britain had dealt with the looming shortage of food by reorganizing its economy. By switching from agriculture to manufacturing, Britain became the first industrialized nation in the world.