Carta XVIII - Carta particolare della parte Orientale del Isola di Iezo con il stretto fra America e la detta Isola

Robert Dudley was an English nobleman, navigator, and cartographer who spent much of his later life in exile in Florence under Medici patronage. His Dell’Arcano del Mare, first published in 1646–47, was reissued in 1661 under the shortened title Arcano del Mare. The atlas was the first printed sea atlas by an Englishman and one of the first to use Mercator’s projection consistently throughout.

This chart shows the eastern part of Isola di Iezo, a landmass representing early European conceptions of Hokkaido and the North Pacific. It was engraved by Antonio Francesco Lucini and does not include the “L.” reference found in many plates from the 1661 edition, consistent with its first-edition issue.

The chart presents a supposed strait between Isola di Iezo and America, reflecting seventeenth-century uncertainty about the relationship between northeastern Asia and northwestern America. Its inscriptions refer to the Mare di Iezo, the Mare del Sur, and the strait between America and Iezo. The sparse coastline, scattered navigational notes, and speculative geography show how little was securely known about this region, even as European mapmakers attempted to connect Japan, Hokkaido, America, and the wider Pacific within a navigable framework.

Within the collection, this chart is closely connected with Dudley’s general Asia chart (222), which also shows uncertain North Pacific geography, and his related Pacific charts (274and 276). It also provides a useful comparison with Vincenzo Coronelli’s Mare del Sud (120), where North Pacific uncertainty remains visible in the treatment of Terra de Iesso.