“You of the West think of time moving in a straight line, from past to present to future. Your eastern brothers regard time as a circle, returning endlessly in a cycle of decay and rebirth. Both ideas have a dimension of the truth. If you were to combine geometrically the movement of the circle with the movement of the line, what would you have?” — Malik
The Helicoid geochronograph of Waterfall City is a water-powered spiral clock tower located within the One-Earth Globe of the city. Combining the concepts of linear and circular time, the geochronograph pictures time as both repeating and advancing. The geochronograph records the history of the entire island and its keeper, known as the Timekeeper of all of Dinotopia, serves as the foremost historian and keeper of time on the island. At the time of Arthur and Will Denison, this position was held by the Stenonychosaurus Malik.
The geochronograph is fashioned in the shape of a spiral or helix, the Dinotopian model for passage of time, which indicates that time does move on but history also repeats itself. The massive tower did not record time based on numbers or concepts such as hours or weeks, which Dinotopians considered meaningless. Instead, the time measurements were based on biological "clocks" such as the life cycle of the local bamboo Guadua trinii.
The massive tower revolved and various important points in time would be marked with whistles, pebbles being dropped on brass bells and flags being raised. The mechanism was powered by flow of water from the network of waterways in Waterfall City, which pushed a waterwell which allowed the entire clock to function.