Now, Doctor Dolittle, while Zuzana was talking over the tea about her letter which she had sent to her cousin—and to which no answer had ever come—suddenly remembered something. On one of his earlier voyages the passenger ship by which he had been traveling had stopped outside this same harbor of Fantippo, although no passengers had gone ashore. And a postman had come aboard to sell a most elegant lot of new green and violet stamps. The Doctor, being at the time a great stamp collector, had bought three whole sets.
And he realized now, as he listened to Zuzana, what was wrong with the Fantippo post office and why she had never got an answer to the letter which would have saved her husband from slavery.
As Zuzana and Begwe rose to go, for it was beginning to get dark, the Doctor noticed a canoe setting out toward his ship from the shore. And in it, when it got near, he saw King Koko himself, coming to the white man's boat with stamps to sell.
So the Doctor got talking to the King and he told him in plain language that he ought to be ashamed of his post office. Then, giving him a cup of China tea, he explained to him how Zuzana's letter had probably never been delivered to her cousin.
"The Doctor gave the king a cup of China tea"
The King listened attentively and understood how his post office had been at fault. And he invited the Doctor to come ashore with Zuzana and Begwe and arrange the post office for him and put it in order so it would work properly.