April 22 Madame du Barry becomes King Louis XV's "official" mistress June 7 Daniel Boone begins exploring Bluegrass State of Kentucky July 16 Father Junipero Serra founds Mission San Diego, 1st mission in California August 18 Gunpowder in Brescia Italy church explodes, killing 3,000 September 18 John Harris builds 1st spinet piano (U.S.) December 12 Pope Clement XIV proclaims a universal jubilee December 13 Dartmouth College in New Hampshire received its charter
