Who started the Great Chicago Fire – Peg Leg Sullivan or Mrs. O’Leary? We can debate it until the cows come home. But one thing that we can’t argue with is the science behind the fire. What made Chicago the perfect storm for this disastrous event? The Chicago History Museum’s City on Fire exhibit gives kids a rare opportunity to peek behind the curtain and see what role science played in how the fire started, how long it lasted and how it hindered the city’s rebuilding efforts.
What materials are most flammable?
From 1861 to 1871, Chicago built a lot of new houses and buildings, mostly made of wood with roofing materials made from tar and flammable shingles. Roads and sidewalks were even planked with wood. What’s more, there were wooden water pipes in the city at the time. In addition to all the wood, businesses used coal, a type of rock that is found underground and can be burned for power and heating. People used kerosene, a kind of oil, and lanterns for light. All of this created a high risk for fire. Towards the beginning of the exhibit, kids can explore the “Will It Burn?” section to see if they can guess what everyday building materials – from straw to coal – are flammable.
Why does fire melt some materials and not others?
As Chicagoans fled the fire, many items that were left behind were caught in the flames. People tried to bury their valuables in hopes of recovering them after the fire, but in the aftermath most items were burned. To make money after the fire, some people began collecting and selling burnt items, such as building nails and books, as souvenirs. Because the fire was so hot, some of these items turned into unique artifacts as items made from metal and glass softened, deformed, melted, and even fused together. The exhibit features some of these artifacts on display such as partially teacups, marbles, and unknown metals. For an interactive experience in the exhibit, kids can put their observation skills to the test to try to guess what the deformed objects (pencils, coin banks, cookies) were before the fire.
How does weather impact fire?
Weather played a huge factor in how the Great Chicago Fire started and how long it lasted. The summer of 1871 was extremely hot and dry. From early July to the outbreak of the fire in October, less than 3 inches of rain – mostly brief showers – had fallen, leaving Chicago in a huge drought. Additionally, it was unseasonably hot in October of 1871 with a high of 85 degrees! When the fire was burning, the super-heated wind sent chunks of the burning city into the air, ultimately starting other fires. When it rained the Tuesday morning after the fire, it finally began to die down after 30 hours. Rebuilding Chicago was also a challenge due to cold winter weather and the inability to mix building materials like cement. Through graphics at the exhibit, little ones can explore visually how weather elements like heat, dryness and wind can contribute to fire.
How did the fire spread so quickly?
They don’t call it the Windy City for nothing! On the day of the fire there were very strong winds. Fire needs oxygen to burn, and the strong winds in the city gave the fire the oxygen it needed to grow. The fire began southwest of downtown and ultimately destroyed the center of the city. These strong winds also helped the single fire spread to eventually become multiple fires, which historians say spread in their own different ways and then recombined. The winds in the area also made it even more difficult to put out the flames. When firefighters tried to hose the fire down, the water turned into mist from the wind. In the exhibit’s “Physics of Fire” video, children can learn how one small fire spread to destroy more than half of the city – 17,500 buildings in a three-and-a-half-mile radius – where at least 300 people were killed and 100,000 were left homeless.
How do advances in technology keep us safe from fires today?
Although the Great Chicago Fire was devastating, the lessons learned and advances in technology as a result keep us safer from fires today. For example, building codes have changed drastically – we don’t have wooden sidewalks anymore and downtown structures are now built of more fire-resistant material like brick and steel. The City on Fire exhibit takes visitors on a journey to experience what the city was like before the fire, and concludes with a “Fire Safety Today” section where families can explore more changes and innovation in fire prevention and how we can all do our part to stay safe.
For more information on the Great Chicago Fire, visit chicagohistory.org.