Wikipedia:Today's featured article/December 29, 2016

The Montreal Laboratory in Montreal, Canada, was established by the National Research Council of Canada during World War II to undertake nuclear research in collaboration with the United Kingdom. After the Fall of France, some French scientists escaped to Britain with their stock of heavy water, and joined the British Tube Alloys project to build an atomic bomb. In 1942, it was decided to relocate the work to Canada. The Montreal Laboratory was established in a house belonging to McGill University, but moved to the Université de Montréal in March 1943. The first laboratory staff arrived at the end of 1942. John Cockcroft became director in May 1944. In August 1943, Mackenzie King, Franklin Roosevelt and Winston Churchill (pictured) negotiated the Quebec Agreement, which merged Tube Alloys with the Manhattan Project. Work moved to the Chalk River Laboratories, which opened in 1944, and the Montreal Laboratory was closed in July 1946. Two reactors were built at Chalk River: the small ZEEP, which went critical in September 1945, and the larger NRX, which followed in July 1947, and was for a time the most powerful research reactor in the world.