The great CHICAGO FIRE burned hundreds, possibly thousands of acres of the Windy City. More than 300 people lost their lives during this tragedy.
One can visit the Chicago History Museum (formerly the Chicago Historical Society), and see all the events in the sequence of their occurence.
Of course Mrs O'Leary--and her cows--have taken alot of "heat"--all puns intended, for this awful event in the life of the City with Big Shoulders.
Out of this fire comes alot of things that have profoundly affected not only Chicago, but the nation as well:
Strong labor unions
Structured emergency systems
A seriousness about personal evangelism that affected the church here in Chicago.
D L Moody vowed to never again insist that someone "go home and think about receiving Christ"--because so many perished before they were offered the opportunity to give their hearts to Jesus.