E J Marey, French scientist and pioneer photogtrapher of movement (called chronophotography), proposed a graphical train schedule that is both timetable and graphic representation of speed.
Above, is his diagram of the Paris-Lyon train service. The speed of the train is expressed by the slope of the line. timed stops are expressed through the visual step in the line.
Below, is Marey’s famous sequential image of the flight of a pelican…one of the most important visual images of the 19C.
You can download the whole of Marey’s, Methode Graphique (1885) as a pdf…
Ed Tufte used this famous diagram on the cover of his book.