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Did the Great Chicago Fire really start with Mrs. O'Leary's cow?

Rounding up the Chicago Fire Suspects

Mrs. O'Leary had five cows, a calf, a horse, two tons of hay, and two tons of coal in the barn in her backyard. Fire hazard? Yes. But this barn and its contents were her livelihood, and they were not insured. Why would Mrs. O'Leary let her business burn to the ground without running for help? Mrs. O'Leary claimed that she never milked her cows in the evening, and furthermore, she was asleep -- in bed early that particular night with a sore foot.

So, if it wasn't Mrs. O'Leary, then who was it?

Mrs. O'Leary testified at the fire inquiry that her neighbors threw a party the night of the fire in the home directly in front of hers. She said she was told later that some party-goers had been spotted going into her barn -- they wanted milk from her cows for either an oyster dinner or a milk punch. Mrs. McLaughlin, the hostess of the party that night, however, said that she served neither dinner at her party nor a punch that required milk.

In 1882, some suggested that Biela's comet had caused the fire. Biela's comet was split into pieces, and the impact of the blast sent large fragments toward Earth. The theory claims that the fragments contained highly combustible chemicals that exploded upon impact, starting not just the Chicago fire, but other fires that burned that night, including fires in Wisconsin and Michigan. While scientists say that meteorites cannot sustain enough heat to ignite fires once they enter Earth's atmosphere, this theory continues to reemerge, most recently in 2004.

One person has even confessed to starting the fire. Louis M. Cohn, a wealthy importer in Chicago, claimed that when he was 18, he was gambling with one of the O'Leary boys in the barn when they accidentally knocked over a lantern. Cohn's story, which included a boastful remark that he was winning when the fire ended the game, did not emerge until after his death in 1942.

With all these different theories, it's difficult to put a finger on the culprit. Yet one man thinks he has figured out who set the fire. We'll take a look at his theory on the next page.

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