In 1877, a French editor mistook the fake invention of "telectroscope" (an electronic telescope that projects images just like a modern TV) as real, and even attributed it to Alexander Graham Bell.
The hoax perpetuated itself through the century and became a reality (in form of an art exhibit) in New York and London, thanks to British artist Paul St. George:
As the first splinters of sunlight spread their warmth on the south bank of the River Thames this morning, it became clear that after more than a century, the vision of Victorian engineer Alexander Stanhope St. George had finally been realized.
In all its optical brilliance and brass and wood, there stood the Telectroscope -- an 11.2 meter (37 feet)long by 3.3 meter (11 feet) tall dream of a device allowing people on one side of the Atlantic to look into its person-size lens and, in real time, see those on the other side via a recently completed tunnel running under the ocean. (Think 19th century Webcam. Or maybe Victorian-age video phone.)