Portolan chart of the Mediterranean Sea and western part of the Black Sea ; Portolan chart of the Aegean Sea and part of the Mediterranean Sea including Crete
Shows names of harbors along the coastlines of the Mediterranean Sea, Black Sea, and adjoining waters.
Relief shown pictorially on the Mediterranean Sea chart.
Statement of attribution from the Aegean Sea chart.
Available also through the Library of Congress Web site as a raster image.
Titles devised by cataloguer.
Aegean Sea chart oriented with north to the right.
The 2 charts are half-joined at the cover spine.
Includes color drawings of cities, flags, illustration of Christ on the cross, and numerous compass roses.
Two circular insets in the Mediterranean chart: America [north and south] -- Europa, Asia, Africa.
In the 17th century, maps took a huge leap forward. Mathematical and astronomical knowledge necessary to make accurate measurements had evolved. English mathematicians had perfected triangulation: navigation and surveying by right-angled triangles. Triangulation allowed navigators to set accurate courses and produced accurate land surveys. Seamen learned to correct their compasses for declination and had determined the existence of annual compass variation. Latitude determination was greatly improved with the John Davis quadrant. The measurement of distance sailed at sea was improved by another English invention, the common log. Longitudinal distance between Europe and Québec was determined by solar and lunar eclipses by the Jesuit Bressani in the 1640s and by Jean Deshayes in 1686. With accurate surveys in Europe, the grid of the modern map began to take shape.