At 5:12 A.M. on Wednesday, April 18, 1906, an earthquake woke up residents of San Francisco and tossed them from their beds. Little did they know that it was going to be one of the deadliest natural disasters in the history of the United States.
The earthquake itself only lasted about 45 seconds, but it was estimated to have been between 7.8 and 8.3 on the Richter scale, which wasn't invented until 1935. When the earth stopped shaking, few people realized that San Francisco's cataclysm had only just begun. Almost immediately, downed power lines, broken gas lines, and damaged chimneys ignited widespread fires. Worse, the quake had cracked the city's massive clay water mains, leaving firefighters virtually without water.
The Fire Vibrated
The fire burned for 72 hours, at times consuming one city block every 30 minutes and eventually charring more than four square miles. Towers of smoke billowed a mile high. The flames reached 2,700°F; even using saltwater lines from the bay and wearing protective wet bags, firefighters couldn't get near the fire. Some observers claimed that the fire could actually be felt as "vibrations like the rumbling of a steam boiler or the passing of several streetcars."
Dynamite Fueled the Flames
City and military authorities attempted to create a firebreak using dynamite and gunpowder. But, inexperienced with explosives, they sometimes failed to check the wind or anticipate the direction of the fire before blasting buildings. Instead of creating a firebreak, they often sent flaming debris to neighboring blocks, spreading the fire faster and farther.
Crowd and Class Control
Half the city's population—over 200,000 people—fled their homes. Refugees packed into every public square, cemetery, and park, with an estimated 50,000 to 90,000 in Golden Gate Park alone. At first people of different classes and ethnicities crowded together on park benches and rubbed elbows in bread lines. Within days, however, enough ugly bias returned to force the Chinese refugees into segregated camps.
The "Great" Debate
Prior to 1906, California entrepreneurs had avoided public discussion of earthquakes, fearing that it would hurt business and discourage investment. After the disaster, James Horsburgh Jr., an agent for Southern Pacific Railroad, wrote to chambers of commerce throughout the state, explaining, "We do no believe in advertising the earthquake. The real calamity in San Francisco was undoubtedly the fire." Likewise, in late April, the San Francisco Real Estate Board passed a resolution saying that "the great fire" should be used instead of "the great earthquake" when referring to the disaster. Acts of God, such as earthquakes, could wreak havoc on real estate values, whereas the familiar threat of fire could be minimized by improved building codes and emergency preparedness.
When Time Stands Still
Each year on April 18th, at exactly 5:12 A.M., hundreds gather to commemorate the 1906 earthquake with a moment of silence at Lotta's Fountain on Market Street.