London smog, 1952 (it claimed 4,000 lives that year alone)

In 1953, smog gets so bad in the shadow of City Hall that pedestrians carry rags to wipe away tears. Scientists began collecting smog particles in the 1950s to analyze what was causing the haze. The primary culprit turns out to be automobiles, not factories.

Photo: City Hall, merely across the street, is dim as Marion E. Lent gropes her way to work. Credit: R.L. Oliver / Los Angeles Times

Our Vintage Times series is presented on Tumblr with photography from the Los Angeles Times archives.