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Hidden secrets of 1491 world map revealed via multispectral imaging



A map of the world produced in 1491 by Henricus Martellus has been subjected to multispectral imaging, which has revealed hidden details on the map not previously visible, including numerous Latin descriptions of regions and people. Henricus Martellus, a German cartographer working in Florence in the late 15th century, produced a highly detailed map of the known world. According to experts, there is strong evidence that Christopher Columbus studied this map and that it influenced his thinking before his fateful voyage. Martellus' map arrived at Yale in 1962, the gift of an anonymous donor. Scholars at the time hailed the map's importance and argued that it could provide a missing link to the cartographic record at the dawn of the Age of Discovery. However, five centuries of fading and scuffing had rendered much of the map's text and other details illegible or invisible, limiting its research value. A team of researchers and imaging specialists is recovering the lost information through a multispectral-imaging project. Their work is yielding discoveries about how the world was viewed over 500 years ago. Last August the five-member team visited the Beinecke Rare Book & Manuscript Library, where for years the Martellus map hung from a wall outside the reading room. (It was recently moved to the Yale University Art Gallery for storage while the library is under renovation.) The team, funded by a grant from the National Endowment for the Humanities, photographed the map in 12 reflective colors, including several frequencies beyond the range of visible light. Those images were processed and analyzed with high-tech software. June 12 http://phys.org/news/2015-06-hidden-secrets-world-revealed-multispectral.html







The work on the imaging was carried out at the Yale University Art Gallery. Shown here is the chart for the Mercury station direct on June 12 at New Haven, Connecticut  where the Gallery is located.  A T-square  comprising  Mercury-Saturn-Neptune is placed on the angles and therefore prominent for the place.


The next question is how do we  discover  the possible meanings latent in any configuration, as pointers to situations or images  that we encounter. One way is to think of keywords or phrases for each planet and then link them together. For example Neptune is the ‘ocean’, Saturn the ‘lord of boundaries’  as well as the ‘capacity for organization’  and Mercury is a ‘collection of data’. Does that fit into a world map showing the land mass as separated from the sea?  How about another combination? Neptune is vague, unclear, foggy, difficult to pin down while Saturn insists on boundaries, definition  and therefore clarity. The new technique of multispectral imaging has helped to reveal details  of a map that had previously been obscured by five centuries of fading and scuffing. Would that not be classified under a Saturn-Neptune project?

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