The Spanish Empire's Governorate of the Río de la Plata and Governorate of Paraguay begin the process of expulsion of the 456 members of the Society of Jesus (the Jesuits) from southern South America, placing them on five ships bound for Spain. October –December October 7 – Frederick North, Lord North becomes the new British Chancellor of the Exchequer after the sudden death of Charles Townshend. October 9 – Surveying of the "Mason–Dixon line", which will later become the traditional division between the northern and southern states of the United States, is completed by Charles Mason and Jeremiah Dixon after four years, initially to settle a boundary dispute between the colonies of Delaware, Pennsylvania and Maryland. The survey party is halted at Dunkard Creek when a chief of the Mohawk Indians tells them that they are in Native American territory and that the Mohawks guiding the property "would not proceed one step further Westward"; the line, slightly west the 80th meridian west, is now part of the boundary between Pennsylvania and West Virginia. October 12 – At the Foundling Hospital in London, Dr. William Watson becomes the first physician to conduct a controlled clinical trial, selecting 32 boys and girls of similar age who have not yet had smallpox. He divides them into three groups in order to test treatments before inoculation for smallpox, with one group receiving a mixture of mercury and jalap, another senna glycoside, and the third getting no pre-treatment at all. October 17 – Šćepan Mali, nicknamed "Stephen the Little", is selected as the legislature at Podgorica to be the Tsar of Montenegro, representing "a short but an important break in the succession of the Petrovic dynasty". October 24 – In France, several anti-Jewish regulations in place since October 12, 1661, are repealed by the King's Council that advises Louis XV of France. While Jewish merchants are still prohibited from owning their own retail stores, they are allowed to sell merchandise on credit to gentile merchants at legal interest rates, to legally enforce debts, and to sell jewelry. October 28 – A boycott, of 38 types of goods imported from England, is resolved by Boston merchants meeting at Faneuil Hall as a response to the taxes imposed by Great Britain, and one of the first "Buy American" campaigns is started in order to encourage the purchase of items manufactured and produced in the 13 colonies. Copies