Napoleon's Buttons: How 17 Molecules Changed History

The authors argue that the chemical structures of a small number of molecules have been pivotal but often unrecognized forces in shaping human history, influencing exploration, trade, war, slavery, industrialization, public health, and social change. The book is organized not chronologically but by chemical connections among molecules, tracing how structurally similar compounds influenced related historical events.

The book opens with the theory that the disintegration of tin buttons in extreme cold may have contributed to the collapse of Napoleon's Grande Armée, the massive French army, during its 1812 retreat from Moscow, when 600,000 soldiers dwindled to fewer than 10,000. The authors acknowledge the theory is unproven but use it to frame the book's premise: Small molecular changes can produce enormous consequences. A primer on organic chemistry, the study of carbon-containing compounds, introduces readers to chemical structures and bonding conventions, demonstrating that the position of a single hydroxyl (OH) group can produce vastly different molecular properties.

The first chapters examine how spice molecules drove the Age of Discovery. Piperine, the compound responsible for pepper's heat, was so valued in medieval Europe that a pound of pepper could buy a serf's freedom. Venice's monopoly on the spice trade prompted Portugal and Spain to seek alternative sea routes, leading Portuguese explorer Vasco da Gama to reach India in 1498 and prompting Christopher Columbus, a Genoese navigator seeking a western route to India's pepper, to reach the Americas in 1492. The English East India Company, formed in 1600, pioneered the selling of shares to spread financial risk, a practice the authors link to the beginnings of modern capitalism. Nutmeg and cloves, even rarer than pepper, inspired Portuguese mariner Ferdinand Magellan's circumnavigation of the globe from 1519 to 1522 and the Dutch East India Company's ruthless consolidation of the Spice Islands in present-day Indonesia. The 1667 Treaty of Breda, in which the Dutch ceded Manhattan to England in exchange for the nutmeg-producing island of Run, illustrates how a single fragrant molecule, isoeugenol, could redraw political boundaries.

The authors argue that while spice molecules fueled exploration, the lack of another molecule nearly ended it. Ascorbic acid, or vitamin C, was the missing compound behind scurvy, which killed more sailors than all other causes combined for centuries. Effective remedies were known but largely ignored: Captain James Lancaster lost no men to scurvy on his flagship in 1601 thanks to bottled lemon juice, while the other ships in his squadron suffered significant casualties. Physician James Lind's 1747 controlled clinical trial proved citrus fruit's effectiveness, yet the British navy delayed implementation for about four decades. Captain James Cook later demonstrated that scurvy was entirely preventable, earning the Royal Society's Copley gold medal not for navigation but for conquering the disease, which enabled his Pacific discoveries.

The book traces a chemical connection from sugar to cotton to explosives. Glucose, the basis of sugar, fueled the transatlantic slave trade: By some estimates, around two-thirds of enslaved Africans in the New World labored on sugar plantations, and sugar revenues from the West Indies provided the capital that launched the British Industrial Revolution. Cellulose, a polymer (a large molecule made of repeating smaller units) of glucose and the main component of cotton fiber, then sustained that revolution. Lancashire, England, became the center of cotton manufacturing, with factory workers enduring terrible conditions including long hours, overcrowded housing, and child labor. The chemical distinction between sugar and cotton lies in a tiny structural difference: The orientation of a single OH group on the glucose molecule determines whether it forms digestible starch or indigestible cellulose. The demand for raw cotton drove a massive expansion of American slavery, making it the central issue of the Civil War.

The chapter on nitro compounds traces how the NO₂ (nitro) group changed civilization. Swedish inventor Alfred Nobel stabilized dangerously unpredictable nitroglycerin by mixing it with diatomaceous earth to create dynamite in 1867, enabling major engineering projects from railway tunnels to the Panama Canal. He left his fortune to fund the Nobel Prizes. German chemist Fritz Haber developed a process for synthesizing ammonia from atmospheric nitrogen by 1913, solving Germany's wartime need for explosives after Britain blockaded Chilean saltpeter supplies. The Haber process now underpins global fertilizer production.

The authors draw a chemical parallel between silk and nylon through the amide bond, a type of chemical linkage, present in both materials. Silk's smooth feel and luster arise from the small, uniform side groups on its amino acids, and silk exports helped finance the Renaissance. Wallace Carothers, hired by Du Pont in 1928, created nylon, a synthetic polyamide—a polymer whose units are linked by amide bonds—whose introduction as stockings in 1939 was an enormous commercial success. Carothers, who had worsening depression, died by suicide in 1937, before nylon reached the market. In a parallel thread, the authors trace phenol from surgeon Joseph Lister's pioneering use of carbolic acid as a surgical antiseptic in the 1860s to Belgian chemist Leo Baekeland's 1907 invention of Bakelite, the first truly synthetic plastic.

The rubber chapter examines isoprene, the molecule responsible for rubber's elasticity. Natural rubber was known to Indigenous peoples of Central and South America for millennia but proved impractical in Europe until American inventor Charles Goodyear accidentally discovered vulcanization in 1839, a process using sulfur to create cross-links between rubber chains. The Amazon rubber boom brought wealth to rubber barons but was built on the exploitation of Indigenous workers through conditions close to slavery. When Japan's 1942 conquest of Southeast Asia cut off Allied rubber supplies, the United States mobilized its chemical industry to produce synthetic rubber on a massive scale.

The dye industry provides another major thread. Eighteen-year-old chemistry student William Henry Perkin's 1856 attempt to synthesize quinine from coal tar accidentally produced mauve, the first synthetic dye, launching the modern organic chemical industry. Germany built a dominant dye industry through BASF, Hoechst, and Bayer, which by 1900 controlled nearly 90 percent of the global dye market and later diversified into pharmaceuticals. Aspirin, developed at Bayer in 1893, and the sulfa drugs—early antimicrobial compounds—and penicillins that followed dramatically increased life expectancy in the twentieth century.

The book examines how steroid chemistry led to the first oral contraceptive. American chemist Russell Marker developed the "Marker degradation," a process for converting compounds from a Mexican wild yam into steroid hormones, making synthetic progesterone affordable. Carl Djerassi at the pharmaceutical company Syntex then synthesized norethindrone, a synthetic progestin—a compound with progesterone-like properties that could be taken orally. Birth-control activist Margaret Sanger and wealthy research funder Katherine McCormick championed the compound as a contraceptive. Approved in 1960, the pill triggered a social revolution by giving women control over their fertility.

The authors devote chapters to alkaloid molecules, plant compounds containing nitrogen atoms that are often physiologically active. They argue that atropine and scopolamine from nightshade plants produced vivid hallucinations in women who applied "flying ointments" to their skin, contributing to their persecution as witches. Ergot alkaloids from fungus-contaminated rye caused community-wide outbreaks of convulsions and gangrene that were blamed on sorcery. Three other alkaloids, morphine, nicotine, and caffeine, converged in the Opium Wars of the 1840s, when Britain forced opium grown in India onto China to pay for tea, breaking down centuries of Chinese isolation.

Oleic acid, the monounsaturated fatty acid in olive oil, underpinned the prosperity of ancient Mediterranean civilizations whose wealth enabled the emergence of democratic ideals, philosophy, and scientific inquiry. Salt, essential to life and historically precious, drove trade routes across the Sahara and was heavily taxed from ancient Rome to British India, where Mahatma Gandhi, leader of India's independence movement, led the 1930 Salt March to help end colonial rule.

The final chapters address chlorocarbon compounds and malaria. Mechanical refrigeration, developed from the 1850s onward and later improved by chlorofluorocarbons (CFCs) in the 1930s, reduced the ancient reliance on spices and salt for food preservation. However, CFCs were found in 1974 to destroy the ozone layer, leading to the 1987 Montreal Protocol requiring a global phaseout. DDT proved enormously effective against malaria-carrying mosquitoes but caused devastating bioaccumulation—a process in which a substance's concentration increases at each level of the food chain—in wildlife. The book closes by linking quinine, DDT, and hemoglobin through their connections to malaria. A tiny change in hemoglobin, the oxygen-carrying protein in blood, produces sickle-cell anemia but also confers resistance to malaria: The substitution of one amino acid at a single position alters roughly one-tenth of 1 percent of the molecule's structure. Slave traders exploited this resistance, as enslaved Africans could survive tropical plantation conditions that killed others, making this molecular variation a factor that sustained centuries of slavery. The authors conclude that predicting which molecule will next change the world is as impossible now as it was for the discoverers whose stories fill these pages.