The Fra Mauro map dates to about 1460, nearly two centuries after Yamen. Sailing ship forms can persist and evolve along recognizable lines for centuries, which makes its vessel drawings a possible broad analogue for regional craft. The map cannot serve as a direct portrait of the 1279 Song navy. The gap in dates limits how much its drawings can tell us about those earlier ships.
Notable Point · 41:31-42:55
Using the Fra Mauro map cautiously for Song ships
A 1460 map can offer a cautious visual analogue for ships used around Yamen nearly two centuries earlier.