alt:
"Projectionists might speed up Edison one- and two-reelers with relative impunity. But Biographs looked ridiculous at anything above the so-called standard 16. By 1913, even that speed was too fast. The chief Biograph director, D. W. Griffith, appeared to be struggling against the limitations of the one- and two-reeler. (The following year, he would embark on his epic The Birth of a Nation in 12 reels.) By slowing the speed of the camera (and therefore the projector) he could squeeze in extra sequences and extend his story. Biograph instructed exhibitors to project their films so that a full 1,000 ft. reel lasted eighteen minutes- 15 fps.
The highly inflammable nitrate film had to move slowly past the searing heat of the arc lamp. On most projectors, the fire shutter would descend and cut off the light if they moved below 40 ft. per minute. Projectionists often ignored the 18 minute-per-thousand rule. One might assume that reports that his actors were zipping across the screen would h"
