A Brief History of World's Fairs

Philadelphia, 1876: Horsepower
Set to commemorate the 100th anniversary of the founding of the United States, the American Centennial Exhibition was the first official world's fair held in the U.S. Among the exhibits was this extraordinary technical marvel, a 1,500-horsepower Corliss steam engine, which powered all the exhibits at the fair. It was the centerpiece of the opening festivities, illustrated above, during which it was turned on by then President Ulysses S. Grant.

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