By 1870 the remaining impediments to growth were less about the technology and more about legal and political matters . In 1870 the '' Chicago Tribune '' reported : The Great Chicago Fire " was a conflagration that burned from Sunday , October 8 , to early Tuesday , October 10 , 1871 . The fire killed up to 300 people , destroyed roughly 3.3 square miles ( 9 km2 ) of Chicago , Illinois , and left more than 100,000 residents homeless . " Armour and his partners apparently came through physically unscathed but their various business affairs were totally disrupted . The offices of Armour , Dole and Co , Munger & Wheeler were destroyed as well as Armour , Dole & Co Elevator " A " , the MLTC offices , the Merchants Insurance Company offices - which were exploded to make a fire break that failed - and the CBT offices
Great Chicago Fire
Great Chicago Fire
George Armour