The Origin of the Term ‘Pea Soup’ for London’s Fog
London has long been associated with its thick, oppressive fogs, which were infamous during the 19th and early 20th centuries. These fogs, however, were not the natural mists one might expect. Instead, they were a lethal combination of pollution and weather, earning the grim nickname “pea soupers.” But why exactly were these fogs called “pea soup,” and what made them such a defining characteristic of London?
The Look of Pea Soup Fog
The term “pea soup” was inspired by the fog’s distinct yellowish-green color, reminiscent of split pea soup. This hue came from the high concentration of pollutants, particularly sulfur dioxide, which was released into the air by the widespread burning of coal for heating and industrial purposes. Mixed with natural mist and smoke from chimneys, this created a dense, acrid smog that could envelop the city for days.
A Product of Industrialization
By the 19th century, London was a hub of industry and home to millions of residents who relied on coal as their primary fuel source. The unchecked burning of coal, combined with the city’s damp climate, created the perfect conditions for these smogs to form. The fog would trap the pollutants close to the ground, creating an almost tangible blanket of smoke and mist that obscured visibility and made breathing difficult.
Health Hazards and the “Great Smog”
The pea soup fogs were not just an inconvenience; they were deadly. The pollutants in the fog caused severe respiratory problems and were especially dangerous for the elderly, children, and those with pre-existing conditions. The most infamous example was the “Great Smog” of December 1952, during which an estimated 4,000 to 12,000 people died from complications related to the smog.
Cultural Significance
The eerie, disorienting nature of pea soup fogs found its way into literature and popular culture. Writers like Charles Dickens and Arthur Conan Doyle described the fog in their works, using it as a symbol of mystery and urban chaos. Sherlock Holmes’s London, for example, often featured foggy streets that added an air of intrigue and danger to his adventures.
The End of Pea Soupers
The Clean Air Act of 1956 marked a turning point in the battle against London’s notorious fog. The legislation introduced measures to reduce air pollution, including restrictions on burning coal in urban areas and the creation of “smokeless zones.” Over time, these efforts drastically reduced the occurrence of pea soup fogs, transforming London’s air quality and putting an end to this infamous phenomenon.
Legacy of the Term
Today, the term “pea soup fog” is a historical reminder of a time when industrialization came at a severe cost to public health and the environment. While London no longer suffers from these deadly fogs, the phrase remains part of the city’s lore, evoking images of a bygone era when the air itself seemed to weigh heavy with the price of progress.
