August 20

The Great Fire of 1910, a wildfire that consumed about 3 million acres in Washington, Idaho and Montana—an area about the size of Connecticut—claimed the lives of 78 firefighters over two days.  It is believed to be the largest, although not deadliest, fire in U.S. history - 1910
 
Deranged relief postal service carrier Patrick “Crazy Pat” Henry Sherrill shoots and kills 14 coworkers, and wounds another six, before killing himself at an Edmond, Okla., postal facility.  Supervisors had ignored warning signs of Sherrill’s instability, investigators later found; the shootings came a day after he had been reprimanded for poor work.  The incident inspired the objectionable term “going postal” - 1986