Canning novelty. Early methods of manufacture employed poisonous lead solder for sealing the cans. Studies in the 1980s attributed the lead from the cans as a factor in the disastrous outcome of the 1845 Franklin expedition to chart and navigate the Northwest Passage. Later studies found this to be false. Increasing mechanization of the canning process, coupled with a huge increase in urban populations across Europe, resulted in a rising demand for canned food. A number of inventions and improvements followed, and by the 1860s smaller machine-made steel cans were possible, and the time to cook food in sealed cans had
Campbell's Soup Cans made the original thirty-two canvases available to the public through an arrangement with the National Gallery of Art in Washington, DC by placing them on permanent loan two days before Warhol's death. However, the original "Campbell's Soup Cans" is now a part of the Museum of Modern Art permanent collection. A print called "Campbell's Soup Cans II" is part of the permanent collection of the Museum of Contemporary Art in Chicago. "200 Campbell's Soup Cans", 1962 (Acrylic on canvas, 72 inches x 100 inches), in the private collection of John and Kimiko Powers is the largest single canvas of the