Montreal was incorporated as a city in 1832. The opening of the Lachine Canal permitted ships to bypass the unnavigable Lachine Rapids, while the construction of the Victoria Bridge established Montreal as a major railway hub. These linked the established Port of Montréal with continental markets and spawned rapid industrialization during the mid 1800s. The economic boom attracted French Canadian labourers from the surrounding countryside to factories in satellite cities such as Saint-Henri and Maisonneuve. Irish immigrants settled in tough working class neighbourhoods such as Point Saint Charles and Griffintown, making English and French linguistic groups roughly equal in size. By 1852, Montreal had 60,000 inhabitants; by 1860, it was the largest city in British North America and the undisputed economic and cultural centre of Canada. Montreal was the capital of the Province of Canada from 1844 to 1849, but lost its status when a Tory mob burnt down the Parliament building to protest passage of the Rebellion Losses Bill.--------------------The city's international status was cemented by Expo 67 and the 1976 Summer Olympics. The mid-1970s ushered in a period of wide-ranging social and political changes, stemming in large part from the concerns of the French-Canadian majority about the conservation of their culture and language, given the traditional predominance of the English-Canadian minority in the business arena. The October Crisis and the election of the separatist political party, the Parti Québécois, resulted in major political, ethnic and linguistic shifts. The extent of the transition was greater than the norm for major urban centres, with social and economic impacts, as a significant number of (mostly anglophone) Montrealers, as well as businesses, migrated to other provinces, away from an uncertain political climate. Bill 101 was passed in 1977 and gave primacy to French as Quebec's (and Montreal's) only official language for government, the main language of business and culture, and enforced the exclusive use of French for public signage and business communication.