"It was still early in the evening and the sky was so luminous that the smoke from the zinc works was a pale shadow against it. Freshly charged, the zinc smelting furnaces, crawling with thousands of small flames, yellow, blue, green, filled the valley with smoke. Acrid and poisonous, worse than anything a steel mill belched forth, it penetrated everywhere, making automobile headlights necessary in Webster's streets, setting the river-boat pilots to cursing God, and destroying every living thing on the hills. Webster lay directly in its path, and in its streets children played, in its dreadful little houses men and women ate and slept, made love and died, perpetually enveloped in smoke. Sometimes the wind shifted and blew it back the other way, over to Donora where another Webster was in the making, no less dreadful, no less hideous; and then Webster's stricken earth, like a scabrous body, lay bared to the clean light of day until the smoke returned and shrouded it."
-- Out of This Furnace by Thomas Bell (1941)7 years before 1948