George Gerner owned George Gerner & Sons, a planing mill. The Great Rogers Park Fire began as a result of sparks flying out from a passing locomotive on the Chicago & North Western Railway tracks to the east of the planing mill. The mill was located at the southwest corner of the block at Greenleaf Avenue and Market Street. It was comprised of one- and two-story frame buildings, occupying 100 feet of ground each way. The fire started either on top or within the boiler room of the mill.