On this day, July 25 …

2019: Politically connected financier Jeffrey Epstein, facing sex trafficking charges, is found injured in his jail cell at the Metropolitan Correctional Center in New York City in what law enforcement officials describe as a possible suicide attempt. (Epstein survives his injuries but would die in an apparent suicide weeks later, on Aug. 10.)

Also on this day …

1866: Ulysses S. Grant is named general of the Army of the United States, the first officer to hold the rank.

1946: The U.S. detonates an atomic bomb near Bikini Atoll in the Pacific in the first underwater test of the device.

1952: Puerto Rico becomes a self-governing commonwealth of the United States.

1960: A Woolworth's store in Greensboro, N.C., that had been the scene of a sit-in protest against its Whites-only lunch counter drops its segregation policy.

1972: The notorious Tuskegee syphilis experiment comes to light as the Associated Press reports that for the previous four decades, the U.S. Public Health Service, in conjunction with the Tuskegee Institute in Alabama, had been allowing poor, rural black male patients with syphilis to go without treatment, even allowing them to die, as a way of studying the disease.

The notorious Tuskegee syphilis experiment comes to light as the Associated Press reports that for the previous four decades, the U.S. Public Health Service, in conjunction with the Tuskegee Institute in Alabama, had been allowing poor, rural black male patients with syphilis to go without treatment, even allowing them to die, as a way of studying the disease. 1978: Louise Joy Brown, the first "test tube baby," is born in Oldham, England.

Louise Joy Brown, the first "test tube baby," is born in Oldham, England. 1984: Soviet cosmonaut Svetlana Savitskaya becomes the first woman to walk in space as she carries out more than three hours of experiments outside the orbiting space station Salyut 7.

Soviet cosmonaut Svetlana Savitskaya becomes the first woman to walk in space as she carries out more than three hours of experiments outside the orbiting space station Salyut 7. 1994: Israeli Prime Minister Yitzhak Rabin and Jordan's King Hussein sign a declaration at the White House ending their countries' 46-year-old formal state of war.