June 21, 1948: Columbia Records introduces the long-playing record album in a public demonstration in New York. Otherwise known as the LP, it played at a speed of 33 revolutions per minute and was soon adopted as the new standard by the entire record industry. One of the advantages of the new format was that each side could play for more than 20 minutes, contrary to the older 78 rpm records, which played for less than five minutes on each side. Apart from relatively minor refinements and the important later addition of stereophonic sound capability, it has remained the standard format for vinyl albums. The average LP has about 1,500 feet (460 m) of groove on each side, or about a third of a mile.
Also on June 21: on non-leap years, the summer solstice in the northern hemisphere and the winter solstice in the southern hemisphere; 1791 – King Louis XVI and Marie Antoinette flee Paris to Varennes in order to initiate a counter-revolution, but are recognised and immediately arrested; 2000 – Section 28 outlawing the “promotion” of homosexuality in the UK is repealed in Scotland; 2006 – Pluto’s newly discovered moons are officially named Nix and Hydra.
Born on June 21: 1905 – French philosopher Jean-Paul Sartre; 1944 – lead singer and songwriter of The Kinks, Ray Davies; 1953 – Benazir Bhutto, the first female Prime Minister of Pakistan; 1982 – Prince William, Duke of Cambridge.