Contained within the 4th Edition (1974) of the Atlas of Canada is a set of three maps. The first map shows sea routes traveled by British, French, Russian and Spanish explorers between 1741 and 1794. The second map shows routes taken by explorers in search of the Northwest Passage during the 16th, 17th, 19th and 20th centuries (1576 to 1944). The third map shows routes taken between 1847 and 1879 by expeditions in search of Sir John Franklin, an explorer who perished in 1847 while in search of the Northwest Passage.