Impossible progress can come quickly. The Information, James Gleick:

“Across the English Channel, a submarine cable twenty-five miles long made the connection between Dover and Calais in 1851. Soon after, a knowledgeable authority warned: “All idea of connecting Europe with America, by lines extending directly across the Atlantic, is utterly impracticable and absurd.” That was in 1852; the impossible was accomplished by 1858.