Depicted in the image, my oldest portuguese escudos banknote for my first post. Deep violet and green on multicolour with Pedro Nunes on the right, in this circulated but more or less in good conditons portuguese banknote. Pedro Nunes , Latin, Petrus Nonius, 1502-1578, was a Portuguese mathematician, geographer, and writer on navigation and geometry and considered to be one of the greatest mathematicians of his time.
