Robert develops a sketchbook idea involving cityscapes, cars and a mirror. The car’s rear-view mirror creates a frame-within-a-frame, with the mirror showing the parallel lines of a city street converging in the distance; outside another set of lines converge. Viewed together produces an effect of parallel cities slightly offset one from the other. What Robert is searching for is an opposition such as forward/ backward, interior/ exterior, motion/ stillness. After listing a few possibilities he writes at the bottom of the page: day/ night. This contrast, used in the finished painting, has the added benefit of suggesting a passage of time.