This view through an open doorway uses the technique of framing to lead the eye into the picture. The table in the foreground, and the doorway frame the farm buildings in the background.

The close-up views below show how varying tone and linework can create the illusion of continuity. The gateway appears light against a dark background and dark against a light background. The eye must be 'helped' to see this in the drawing which must convey what the eye is used to seeing even if it is an illusion. Similarly, in the second close-up the three branches on the left appear to be the same but one is black and the other two are white.