On the warm evening of Sunday, October 8, Daniel “Peg Leg” Sullivan, a one-legged wagon driver, visited neighbors on Chicago’s West Side. He stopped at the home of Patrick and Catherine O’Leary at around eight o’clock in the evening but left quickly because the family had already gone to bed—Patrick to prepare for his laborer’s job and Catherine to milk the family’s cows before delivering milk to neighbors the next morning. Sullivan sat down on the wooden sidewalk across the street in front of Thomas White’s house. Nearby, the McLaughlins were hosting a party for a relative newly arrived from Ireland. At 8:30 pm, another neighbor, Dennis Rogan, also stopped by the O’Learys and found them asleep.

About 15 minutes later, as Sullivan rose to head home, he spotted a single flame shooting from the side of the O’Learys’ barn and immediately raised the alarm. He rushed inside to save the animals—five cows, a calf, and a horse—but the terrified animals wouldn’t move. As the fire spread behind him, he slipped on the uneven floorboards, and his wooden leg jammed between the boards and came off. He hopped toward the door. The O’Learys’ calf bumped into him, and he grabbed its neck; they escaped together, both badly singed. An attached shed full of coal and kindling was already burning, and flames raced through dry grass and fences until the O’Learys’ cottage, 40 feet away, began to smolder. Neighbors rushed out with buckets, and the party music stopped, replaced by cries of “FIRE!”

Murphy then explains why Chicago was so vulnerable. Of the city’s 59,500 buildings, roughly two-thirds were wood. Even structures described as fireproof typically concealed wooden frames and flammable tar or shingle roofs behind brick or stone facades, and decorative exterior details were almost universally carved wood painted to resemble stone or marble. Residential neighborhoods were packed with cottages, barns, and sheds on small lots, and over 55 miles of pine-block streets and 600 miles of wooden sidewalks made large areas of the city highly combustible. Fires had been increasing in number for years, and a severe summer drought had left the landscape extremely dry by October—as many as six fires broke out daily, and the Saturday before had seen a blaze that destroyed four city blocks. What made Sunday especially dangerous was a strong, gusty southwest wind.

That wind pushed the fire from the O’Leary barn into neighboring yards. Rogan returned and woke the O’Learys, and they got their children out of the house while Patrick and a group of neighbors repeatedly doused the cottage, which survived with little damage. Down the block, William Lee, a neighbor, checked on his crying infant and saw a crimson sky and embers falling in his yard. He ran three blocks to Bruno Goll’s drugstore to turn in a fire alarm while the fire was still less than 15 minutes old. What followed was a series of fatal errors that allowed the fire to spread unchecked.

Lee arrived at Goll’s drugstore gasping, but Goll refused to hand over the alarm key, insisting that an engine had already passed. Lee rushed back to find fire taking hold of his neighbor’s shed and fence and threatening his own house. His wife grabbed their infant and carried him outside while Lee collected a few essentials; the family spent the night watching the fire from a nearby vacant lot, joined by the singed calf that Sullivan had helped escape from the O’Leary barn. Goll later claimed to have sent two alarms, but no alarm was recorded at the central office while the fire was still containable. He ultimately locked up his store and walked to De Koven Street to watch the blaze along with the growing crowd.

At the courthouse, Mathias Schaffer, the 40-year-old cupola watchman, initially mistook smoke pointed out by a visitor for lingering embers from the previous night’s fire. When he finally spotted active flames, he misjudged their location because the new blaze sat almost directly behind the still-smoldering Saturday fire site. At 9:30 pm, he signaled box 342, sending engines racing to a spot nearly a mile from the O’Learys’. He soon realized his error and ordered his assistant, William J. Brown, to strike box 319—still seven blocks off but close enough that crews could see the flames and correct course. Brown refused, insisting that a second signal would only cause confusion. The misdirected alarm pulled engines away from the real fire and caused nearby companies, which had already prepared to roll, to stand down. Only two companies weren’t fooled.

Reporter Joseph E. Chamberlin reached the scene within minutes and found that the fire had already advanced about a block through the crowded frame buildings near De Koven and Jefferson Streets. He was contemptuous of the poor neighborhood and its residents, a bias that would later help fix public blame on Catherine O’Leary and her cow. The first two units to arrive—America, a hose cart, and Little Giant, the oldest engine in service—lacked the power to throw water far enough to be effective, forcing crews to stand dangerously close to the flames. Chief Marshal Robert A. Williams, head of the fire department, arrived and worked to encircle the blaze, ordering foreman John Dorsey to turn in a second alarm. Chamberlin, meanwhile, was forced to retreat as a fence ignited right where he had been standing moments before.

Across the city, 12-year-old Claire Innes was briefly jolted awake in her home in the South Division, one of the city’s three main sections, by a passing wagon and street noise. Her father investigated but seemed unconcerned, and Claire went back to sleep. Many others in Chicago showed similar unconcern. That same day’s Chicago Tribune had warned of extreme fire danger after three weeks without rain, but few paid attention. Alfred L. Sewell, strolling through the city at around 9:30 pm, found beerhouses full and people happily out in the warm evening. Even Horace White, the Tribune’s own editor-in-chief, heard the courthouse bell but didn’t bother to get out of bed.

When Dorsey reached the alarm box at Goll’s drugstore, he pulled the lever only once instead of four times and failed to trigger a true second alarm. Schaffer and Brown heard the single strike, mistook it for a duplicate of the original signal, and dispatched no additional engines. The fire had now been burning for over an hour.

Williams assembled a thin ring of engines around the blaze and asked spectators to help by chopping up wooden fences and sidewalks to deprive the fire of fuel. James H. Hildreth arrived and proposed blowing up houses to create a firebreak. Williams lacked both the authority and the explosives but sent Hildreth off to find powder anyway. Meanwhile, firefighter Charles Anderson and his friend Charles McConners struggled against the heat; McConners propped up a wooden door as a makeshift shield, but it caught fire and burned his hand. The fire’s powerful updraft launched flaming debris high into the air, and the wind scattered burning material over the firefighters’ heads, igniting spot fires behind the defensive line. When a more powerful steamer arrived and pulled Anderson’s hose from the water plug, his water dropped to a trickle, and several houses across the street ignited before he could act. A second steamer also malfunctioned and was briefly repaired; then, at around 10:30 pm, an old section of hose burst entirely. With two breaks developing in the firefighting line, the wind drove the fire past the firefighters and toward the center of the city. As one firefighter later put it, “From the beginning of that fatal fire, everything went wrong!” (42).