April 16

April 16 is the 107th day of the year, and the American record for it runs from 1862 to 2008 — a span of 146 years. The entry that anchors it: U.S. civil rights campaigner Dr. Martin Luther King Jr. writes his open letter from Birmingham Jail, 1963.

By the middle of the nineteenth century the date carries heavier freight. In 1862, Slavery in Washington, D.C., ended when the District of Columbia Compensated Emancipation Act became law. A year later, in 1863, American Civil War — during the Vicksburg Campaign, gunboats commanded by acting Rear Admiral David Dixon Porter run downriver past Confederate artillery batteries at Vicksburg.

The postwar entries show a nation both expanding and contesting itself. In 1947, American financier and presidential adviser Bernard Baruch first described the post–World War II tensions between the Soviet Union and the United States as a "cold war" The same year, an explosion on board a freighter in port causes Texas City in the state of Texas, United States, to catch fire, killing almost 600 people. Then, in 1963, U.S. civil rights campaigner Dr. Martin Luther King Jr. writes his open letter from Birmingham Jail, sometimes known as "The Negro Is Your Brother", while incarcerated in Birmingham, Alabama, for protesting against segregation. Nine years on, in 1972, Apollo program — the launch of Apollo 16 from Cape Canaveral, Florida.

Closer to the present, the date is still accumulating. In 2007, in one of the deadliest shooting incidents in United States history, a gunman killed 32 people and wounded over 20 more before committing suicide at the Virginia Polytechnic Institute and State University in Blacksburg, Virginia. A year later, in 2008, the U.S. Supreme Court rules in the Baze v. Rees decision that execution by lethal injection does not violate the Eighth Amendment ban against cruel and unusual punishment.

The date is also a birthday. Among the Americans born on April 16: Caleb Blood Smith (1808), American journalist, lawyer, and politician, sixth United States Secretary of the Interior; Wilbur Wright (1867), American inventor; Seth Bingham (1882), American organist and composer; Michalis Dorizas (1886), Greek-American football player and javelin thrower; and Gertrude Chandler Warner (1890), American author and educator.

April 16 is also a date of endings. Among the Americans who died on it: George William Hill (1914), American astronomer and mathematician; Nelson W. Aldrich (1915), American businessman and politician; George Wilbur Peck (1916), American politician, 17th Governor of Wisconsin; and Jay Johnson Morrow (1937), American military engineer and politician, third Governor of the Panama Canal Zone.

The date carries formal observance as well — Birthday of José de Diego (Puerto Rico, United States); Emancipation Day (Washington, D.C., United States); and National Healthcare Decisions Day (United States). 8 entries, 146 years, one square on the calendar. April 16 is a reminder that history is experienced as an ordinary day before it is remembered as a date.