One of those maps had been of trade-routes: straight lines joining city to city. Jack could not read the labels. He could identify London and a few other cities by their positions, and Eliza helped him read the names of the others. But one city had no label, and its position along the Dutch coast was impossible to read: so many lines had converged on it that the city itself, and its whole vicinity, were a prickly ink-lake, a black sun. The next time they'd seen the Doctor, Jack had triumphantly pointed out to him that his map was defective. The arch-Librarian had merely shrugged.