This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Dials on Tide Predicting Machine No. . en Dials for tide height outer ring date and time on Tide Predicting Machine No special purpose mechanical analog computer for predicting the height and time of high and low tides When the machine was in operation the operator recorded the height and time of high and low tides which were later