The first practical can opener was developed 50 years after the birth of the metal can. Canned food was invented for the British Navy in 1813. Made of solid iron, the cans usually weighed more than the food they held! The inventor, Peter Durand, was guilty of an incredible oversight. Though he figured out how to seal food into cans, he gave little thought to how to get it out again. Instructions read: "Cut round the top near the outer edge with a chisel and hammer." Only when thinner steel cans came into use in the 1860s could the can opener be invented. The first (patented in 1858), devised by Ezra Warner of Waterbury, Connecticut, looked like a bent bayonet. Its large curved blade was driven into a can’s rim, then forcibly worked around its edge. Stranger yet, this first type of can opener never left the grocery store. A clerk had to open each can before it was taken away!
The modern can opener, with a cutting wheel that rolls around the rim, was invented by William Lyman of the United States in 1870. The only change from the original patent was the introduction of a serrated rotation wheel by the Star Can Company of San Francisco in 1925. The basic principle continues to be used on the modern can openers, and it was the basis of the first electric can opener, intorduced in December 1931. Pull-open cans, patented by Ermal Fraze of Ohio, debuted in 1966.
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