Published on: October 8, 2011 at 9:30 AM

Legend has it that the fire was caused by Mrs. O’Leary’s cow.

The official investigation by the Chicago Fire Department concluded that the Great Chicago Fire did begin in the barn of Mr. Patrick O’Leary on the South Side.

Whether or not it was Mrs. O’Leary’s cow, the Great Chicago Fire was a terrible disaster.

A terrible summer drought had left much of the Midwest, including the city of Chicago as dry as a tinderbox.  Many areas of the city were very congested with narrow streets of wood frame buildings.

The fire started just after 9 p.m. and spread rapidly northward, driven by a strong southwesterly wind. The fire split into separate tongues of flame, consuming everything in its path.

The flames jumped the Chicago River around midnight.  The fire knocked the city’s water works out of commission and then there was nothing to stop it.

17,500 buildings wee destroyed in the flames.  2100 acres were burned.  250 people were killed and 100,000 were left homeless in the city of about 334,000 residents.  Damage totaled $196 million.

The fired raged out of control all day on Monday, October 9, finally being extinguished by the combination of a light rain and the natural obstacle of Lake Michigan.

Some feel that the fire was a blessing in disguise, that it wiped away the cheaply constructed wood frame buildings and allowed Chicago to be built back better prepared for the future.

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