Dec. 9, 1952: 'Killer Fog' smothers up to 12,000 Londoners

London's thick, viscous fogs are world renowned. No less a person than Charles Dickens memorialized these "pea-soupers" in his dictionary of city life, writing:

At such times almost all the senses have their share of trouble. Not only does a strange and worse than Cimmerian darkness hide familiar landmarks from the sight, but the taste and sense of smell are offended by an unhallowed compound of flavours, and all things become greasy and clammy to the touch.

While Dickens decided that the "happiest man is he who can stay at home," that wasn't always an option for the working class of industrial England. That's why, when a particularly gruesome miasma descended over the city in December 1952, thousands of unfortunate souls fell victim to the smothering air and passed away in respiratory hell.

The Great Smog of 1952, also known as the Killer Fog, was caused by a punishing alignment of weather patterns and coal pollution. (The Great Smog should not be confused with the Great Stink, another noxious bit of London history.) Back then, the city was pockmarked with factories and power plants that incinerated thousands of tons of carbon, belching out nose-turning fumes that built up for years in the local atmosphere. There was even more pollution than usual in 1952, too, because an especially cold November had Londoners burning record amounts of coal to stay warm.

At the same time a high-pressure system was drifting over the U.K., creating a temperature inversion that slammed a lid on nasty air trying to rise. A near-lack of wind assured that the toxic brew stayed put, filtering through the graying lungs of London's children and old and infirm. On the morning of Dec. 5, moist ground and clear skies set up the perfect scenario for the development of radiation fog.

Visibility on the streets grew so bad that conductors had to walk in front of their buses with torches so that their vehicles wouldn't crash into anything. Birds, blinded, crashed into structures and perished. Farmers fashioned crude "smog masks" for their precious livestock, a creepy-enough invention of necessity:

Photos via BBC News

The sediment-filled air, which by Dickens' account held pieces of chimney soot as "big as full-grown snow-flakes," was a death sentence for anybody with respiratory issues. People began to pass away on Dec. 5 and continued to drop through Dec. 9, when the foulness began to clear. The mortality rate remained elevated past Christmas. Here is the BBC's account of the terrible scenes during the thick of it:

The air was not only dark, tinged with yellow, but stank of rotten eggs. This is because the fog was laced with sulphur and other toxins in the smoke from coal fires. Those who ventured out into the soot-choked air recall returning home with their faces and clothes - even petticoats - blackened. Some were bought to their knees, coughing uncontrollably.

Contemporary accounts put the death toll around 4,000. However, a more recent study slides the number of premature deaths up to 12,000. The British government seized the opportunity to crack down on pollution, passing the Clear Air Act of 1956, which put restrictions on chimney heights and moved some coal plants away from city centers. However, dense smogs were stilling killing people by the hundreds into the 1960s.

For more photos of this uncanny killer fog, visit here.