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 which the varieties were introduced by the Campbell Soup Company, beginning with "Tomato" in the upper left, which debuted in 1897. By April 2011, the curators at the MoMA had reordered the varieties, moving "Clam Chowder" to the upper left and "Tomato" to the bottom of the four rows. Several anecdotal stories supposedly explain why Warhol chose Campbell's Soup cans as the focal point of his pop art. One reason is that he needed a new subject after he abandoned comic strips, a move taken in part due to his respect for the refined work of Roy Lichtenstein. According to