He predicted that the 1910 appearance of Halley's Comet "would impregnate that atmosphere and possibly snuff out all life on the planet", but not the planet itself. "Comet pills" were sold to protect against toxic gases. The comet indicated the Second Coming to many
Ten Notable Apocalypses That (Obviously) Didn't Happen. Smithsonian. 2009-11-12. Retrieved 2009-11-14.