Summary: Film showing the importance of charts and maps in sea journeys.
Description: An oil tanker is shown in transit; the importance of accuracy in navigation is stressed. The work of the Royal Navy's Hydrographic Department: the ships they have at sea, which are floating laboratories; the making of charts; surveying the shoreline in small boats; summary and simplification of the results that they find; the final charts that are produced. The history of sea surveys: early charts; the genius of Captain James Cook; the modern process of producing and printing these charts; who uses these charts. The amount of work that is left to be done is indicated.
