The heat is on across the country. Learn how to stay cool -- and safe -- when the mercury rises.
Heat-related deaths and illness are preventable yet annually many people succumb to extreme heat.
U.S. Air Force
Vivaldi and Bach die, the first hamburger is sold in the U.S., World War I breaks out, a bomber crashes into the Empire State Building, and the Summer Olympics open up in Los Angeles, all on this day.