In chapter four, McCloud talks about different ways that time can be represented within the frame. A frame is usually not just a single moment. Sound or movement adds duration to the frame. Likewise, the size of the frame and the amount of space between frames can be used to suggest the passage of time. Furthermore, a sense of timelessness can sometimes be achieved by a silent frame, although this depends largely on the content of the frame.
McCloud goes on to talk about Duchamp’s concept of movement (the single line) as well as the Futurist’s dynamic movement (the object in different positions in the same image). These were both precursors to the motion line that is used in most American comics today.