Final answer:
The 'time lost' after the fire spread from the O'Leary's barn refers to the disruption and delay in normal activities due to the Great Chicago Fire of 1871. The fire led to significant destruction which required considerable time for rebuilding and recovery.
Step-by-step explanation:
The fire spread from the O'Leary's barn is a reference to the Great Chicago Fire of 1871. The theory is that it started in the O'Leary's barn, though the exact cause of the fire is unknown. The phrase 'time to be lost' could be interpreted as the disruptions that resulted from the fire. This massive fire led to significant infrastructural damage which required a long period of rebuilding, in effect 'losing' time originally intended for other tasks.
The chaotic conditions of the fire also would have disrupted normal schedules and routines, hence causing 'lost time'. However, this is not a 'loss' in real physical time, but rather, a disruption to human activity and progress during that period.
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