This is the earliest known 2-dimensional charts (plotting time vs. celestial latitude; an apparent anomaly is that it appears to show the celestial latitude of the sun varying with time); the scribe used horizontal and vertical lines as aids, resulting in a picture strikingly similar to modern graph paper as it did not become commonly used before the mid 19th century, some 700 years later. This picture is a notable anomaly, as the earliest comparable "graph" diagram do not emerge prior to the late medieval period, some 250 years after this drawing was made. The graph was first described by Günther (1877).

Literature

• S. Günther, "Die Anfänge und Entwickelungsstadien des Coordinatenprincipes", Abhandlungen der naturhistorischen Gesellschaft zu Nürnberg VI (1877) p. 19
• H. G. Funkhouser, "A note on a tenth century graph", Osiris 1 (1936), 260-262.
• James R. Beniger and Dorothy L. Robyn (1978). "Quantitative graphics in statistics: A brief history", The American Statistician 32 (1978), 1–11.