A “Hellish Cloud” Descended on Los Angeles in 1943: It marked the city's first smog incident. Here’s what it looked like—back then and over the years that followed.

A “Hellish Cloud” Descended on Los Angeles in 1943: It marked the city's first smog incident. Here’s what it looked like—back then and over the years that followed.

On July 26, 1943, Los Angeles was hit by a cloud so thick and irritating that residents feared the city was under a chemical attack. Visibility fell to about three blocks, while…