to make another point in our argument that pictorial motions may sometimes be in dynamic repose. It is quite possible for a pictorial motion to give a sharp impression of power, weight, and velocity, and yet stay practically where it first appears on the screen. An express train, for example, may be shown in a "long shot" starting several hundred yards away from the camera and continuing for miles into the distance, and yet the actual moving image on the screen might cover an area less than two feet square, and might, from beginning to end of the scene, never come near the frame of the picture. Thus the train, without losing any of its impressive character, would provide a reposeful motion for the eye to gaze upon. Surely such an effect would be better than to show the train as a close-up on a track at right angles to our line of sight, with the locomotive crashing in through the frame at the left of the picture and crashing out through the frame at the right.
The reposeful quality of restricted movement on the screen is due partly to the fact that the flicker and the eye movement is thus reduced, as we have said in Chapter III. In the case just described it is due also to the contrast between the slight movement which we actually look at and the large movement which we really perceive and feel. We look at inches and perceive miles. Thus we see very much with extreme ease.
We have remarked in preceding chapters that every picture has four lines, those of the frame, which the composer must always consider. He could, it is true, soften the sharp boundaries of the picture by using some masking device with the camera, but this is not
