Various writers have discussed the origins of the nautical chart. In this paper we wish to show how the marine cartographer has responded to developments in navigation and the changing needs of shipping. The development of the chart has been greatly affected by changes in navigational techniques. For example, Portulan charts, with their criss-crossing loxodromes, developed from a need to illustrate the pilots books, called ‘Portulans’ by the Italians. On these were carefully recorded bearings and distances between points of departure and arrival. As the measurement of latitude became established, the graduation of latitude began to appear on charts early in the sixteenth century. Problems developed on longer voyages through the convergence of the meridians which were temporarily overcome by the use of an oblique meridian. In 1569 the solution to this was finally found when Gerardus Mercator published his famous world map, although the general use of this projection did not take place until much later. Charts of the sixteenth century showed considerable detail and even at that early date there were some who questioned the need to show information that was considered redundant. Bourne, writing in 1574, deplored the hydro-graphers' practice of filling vacant spaces of land ‘with so many flagges’ and colouring the compasses ‘with so many colours’ and that instead of wasting their time, they should include tidal information and the elevation of the shore from the sea.