This article is from the U2 FAQ, by Maryann Stump firstname.lastname@example.org with numerous contributions by others.
The video is a takeoff on an old experiment using motion photography
[email@example.com] The photographer is Edward Muybridge who did hundreds of
motion studies during the late
1800's. This started as a bet between two rich guys and Muybridge was
hired to settle the bet with his invention
of a series of many still cameras set up with wire triggers rigged to
expose film as a horse ran past. The
resulting set of time-lapse prints formed the first 'photo flip book'.
He proved that a horse indeed has all four
legs in the air at a point during a run. If you look up these photos at
your local library you will see where the
styling for parts of the Lemon video came from.