Captain Le Vert Coleman of the Presidio Artillery Corps reported, "During the first day of the fire, and until the evening of the second day, the city authorities withheld their permission to blow up buildings except those in immediate contact with those already ablaze."

Such caution hampered Coleman's progress until Wednesday night, when General Funston met with the Citizen's Committee—the Mayor's appointed relief and recovery organization. With a situation map at hand, Funston outlined his plan to stop the fires through the use of dynamite. Though the strategy was risky, the Committee had few other options and eventually agreed to demolish some buildings in order to save others. Following civilian evacuation of the condemned city blocks, the dangerous task began. Captain Coleman described the complicated and hazardous work of the dynamiting party: "The charges often had to be laid in buildings already on fire; the dynamite had to be carried by hand through showers of sparks; the wires constantly shortened by repeated explosions, could be replaced only by climbing poles in the burning district and cutting down street wires."

By the evening of April 19, the army began preparations to create the firebreak at an east-west division of the city along Van Ness Avenue with its affluent mansions. Funston and his officers, as well as the Mayor and members of the Citizen's Committee, watched in silence as three blocks of expensive houses fell every twenty minutes. The next day, winds blew the fire northward in the direction of Fort Mason, where Army troops hastily pumped bay water to the few fire engines outside the firestorm. Meanwhile, the fire’s southward progression to the Mission District was fought by fire department members and volunteers. Then, on April 21, the fire simply stopped in the center of a block filled with wooden frame houses, ending three days of destruction that had consumed nearly five square miles (over five hundred city blocks) of homes, businesses, and warehouses.

Two days later explosions again echoed in the destroyed city as the weakened remains of structures were felled by military blasts. "The walls, some of them seven stories high, being in a tottering condition, the civilian riggers would not tackle them," reported Captain Coleman.

Coleman was absolute in his assessment of the dynamite demolitions, insisting that "The fire would unquestionably have destroyed the unburnt portion of the city" without them. Not all agreed, however, and the debate over whether dynamiting caused or prevented significant damage continues today.