March 17

March 17 is the 77th day of the year, and the American record for it runs from 1776 to 1973 — a span of 197 years. The entry that anchors it: American Revolutionary War, 1776.

In the years around independence, the date turns political. In 1776, American Revolutionary War — the British Army evacuates Boston, ending the Siege of Boston, after George Washington and Henry Knox place artillery in positions overlooking the city. The same year, American Revolutionary War — the 11‑month Siege of Boston ended with the evacuation of the city's British garrison.

In the first half of the twentieth century the date turns technological. In 1902, the Dorchester Heights Monument , memorializing the siege of Boston during the American Revolutionary War, was dedicated.

The postwar entries show a nation both expanding and contesting itself. In 1958, the United States launches the first solar-powered satellite, which is also the first satellite to achieve a long-term orbit. Two years on, in 1960, U.S. President Dwight D. Eisenhower signs the National Security Council directive on the anti-Cuban covert action program that will ultimately lead to the Bay of Pigs Invasion. Eight years on, in 1968, six thousand sheep were killed on ranches near Dugway Proving Ground in Utah as a result of the U.S. Army spraying a nerve agent. The same year, as a result of nerve gas testing by the U.S. Army Chemical Corps in Skull Valley, Utah, over 6,000 sheep are found dead. Five years on, in 1973, Slava Veder took his Pulitzer Prize-winning photograph Burst of Joy, which came to symbolize the end of United States involvement in the Vietnam War.

The date is also a birthday. Among the Americans born on March 17: Lachlan McIntosh (1725), Scottish-American general and politician; Roger B. Taney (1777), American politician and jurist, 5th Chief Justice of the United States; Jim Bridger (1804), American fur trader and explorer; Charles F. Brush (1849), American businessman and philanthropist, co-invented the Arc lamp; and Cornelia Clapp (1849), American marine biologist.

March 17 is also a date of endings. Among the Americans who died on it: Mike (1947), American Wyandotte chicken, lived 18 months following decapitation (h. 1945); Fred Allen (1956), American actor, comedian, screenwriter, and author; Susanna M. Salter (1961), American activist and politician; and Amos Alonzo Stagg (1965), American football player and coach.

8 entries, 197 years, one square on the calendar. March 17 is a reminder that history is experienced as an ordinary day before it is remembered as a date.