And why is calling it India ink any better? It came originally from china., the capital of which at the time the Portuguese came was in Nanjing. Think of it like Peking duck. Not the color, but where it's from. I saw from the Portuguese Wikipedia that it's called tinta da china in European and tinta nanquim in Brazilian Portuguese. In Chinese, nan means 'south' and jing means 'capital (city)'. Bei means north, so Beijing means 'north capital (city)'.

Ceci n'est pas un seing.