hospital in the American colonies, is chartered in Philadelphia by the Pennsylvania legislature, which grants the right to Benjamin Franklin and to Dr. Thomas Bond. <ref>Thomas G. Morton and Frank Woodbury, The History of the Pennsylvania Hospital, 1751-1895"' (Philadelphia Times Printing House, 1895) p376</ref> May 27 (May 13 Old Style) – Adoption of the Gregorian calendar: Royal assent is given to An Act for Regulating the Commencement of the Year; and for Correcting the Calendar now in Use (the "Calendar Act") passed by the Parliament of Great Britain, introducing the Gregorian Calendar, correcting the eleven-day difference between Old Style and New Style dates and making 1 January legally New Year's Day from 1752 in the British Empire. It is largely promoted by George Parker, 2nd Earl of Macclesfield. June 14 – The colony of South Carolina reverses a 10-year-old law that had imposed a tax of 100 pounds sterling on the purchase of imported African slaves, and reduces the tax to £10. The move effectively restores the slave trade to the colony. June 28 – The first volume of Denis Diderot's Encyclopédie, ou dictionnaire raisonné des sciences, des arts et des métiers, often referred to as le Encyclopédie, is published July–September July 28 – Battle of Kirkhbulakh: The Kingdom of Kartli defeats a large army of the Tabriz Khanate, under Erekle II. July 31 – Fire destroys 1,000 houses in Stockholm. August 13 – The Academy and College of Philadelphia, predecessor to the private University of Pennsylvania, opens its doors, with Benjamin Franklin as president. September 13 – Kalvária Banská Štiavnica in the Kingdom of Hungary is completed. October–December October 22 – William V, Prince of Orange, the three-year-old son of the late William IV, becomes the last Stadtholder of the Dutch Republic. During his minority, his mother, Princess Anne, acts as regent until her death in 1759. Upon becoming of age in 1766, he will have a corrupt reign as the Republic's head of state until the office is abolished on February 23, 1785. October 27 – The Hōreki period begins in Japan. November 14 – The 50-day long siege of the British fort of Trichinopoly (now Tiruchirappalli) in southern India is broken when the defenders use musket fire to force a stampede of the elephants of the French-backed troops of Chanda Sahib. November 17 – Future United States President George Washington becomes seriously ill with smallpox while he