Bianco world map

The Bianco map (1436)

Andrea Bianco was an Italian sailor and cartographer of the 15th century. His Atlante Nautico of 1436 comprises ten leaves of vellum, measuring 26 × 38 cm., and was in an 18th-century binding. This has now been removed and the pages separated by the holders of the charts, Biblioteca Marciana, Venice Italy. The first leaf or tavola 1 is a diagrammatic description of the Raxon or Toleta of Marteloio, which allows seamen to calculate a return to the desired course having been blown aside by winds. There is also the "Tondo e Quadro" ("circle and square") for drawing out the invalid and true courses, thus enabling the visual return course to be seen and measured. The two main tables are actually one and the same with a smaller table giving a one tenth distance measure of the two larger tables. The three other diagrams are actually no more than the wind colouration examples with a beautifully drawn Wind Rose, but drawn at 90 degrees to the Tondo e Quadro format.In the top left corner is a text which instructs the use and purpose of the Tondo e Quadro and the tables. Quite fascinating though is the addition of a Flag containing the text, "Andreas Biancho de Veneciis me fecit M cccc xxx vj", thus confirming the authorship and date. The next eight leaves contain seven local and one Europe wide Portolan Charts (navigation charts). The ninth leaf contains a circular world map measuring 24 cm in circumference and is the same dimension as the wind rose circles on the preceding 8 charts. Thus Andreas Biancho has used the same size vellum and dimensions to construct the Atlante Nautico. The final leaf illustrates a Ptolemaic world map which appears to be based upon Ptolemy's first projection. with graduation of the latitudes, but by Klima zone not degrees. The map also has two texts which give differing measurements for the world sphere. Andreas Biancho also collaborated with Fra Mauro on the Fra Mauro world map of 1459.

Bianco world map

See also