When direction and velocity are controlled, even a single moving spot may describe beautiful motion. Witness an airplane maneuvering high in the sky, or a torch waved gracefully in the darkness. Beauty springs from control; ugliness follows lack of control. But control is no easy thing in the movies, for it is rare indeed that a director has only a single moving point to manage. Almost always, he has the problem of relative direction and relative speed. Moving things must be related to other moving things, and also to fixed things. Even if the picture consists only of a torch waved against a black background, we have the problem of relating that motion to the four fixed lines of the frame of the screen.
But can we expect a motion picture director to stop and think of so small a matter as a ball thrown from one hand to another, to ask himself whether such an action is beautifully related, in direction and velocity, to everything else in the picture, fixed or moving? Yes, we can expect him to do so until he becomes artist enough to think of these matters without stopping. He should think about pictorial composition until he can obey its laws without thought. Let him remember that even a flock of geese can compose themselves so appealingly in the sky and a herd of cows can wind so gracefully down a hillside that a tender girl and a tough hobo will gaze alike upon them in open-mouthed admiration.
The geese in the sky and the cows on the hillside are only a lot of moving spots, until they arrange, or compose, themselves. They may then illustrate the second type of moving object, that of the moving line. A line may, for example, move along its own
