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When the doctor first comes to Kino and Juana's hut, he is aware of the fabulous pearl Kino has found and is already imagining what he could do with such a valuable payment for his services. "The news came to the doctor…And the doctor's eyes rolled up a little in their fat hammocks and he thought of Paris."
It was important, therefore, for the doctor to find a reason to treat Coyotito, even though the swelling in the baby's shoulder had subsided - Juana's treatment with the seaweed had been effective. However, the doctor examines the wound carefully and makes a show of giving Coyotito a capsule containing a white powder. Kino is suspicious of the doctor's actions but recognizes his ignorance and inability to argue with the treatment. The doctor informs Kino and Juana that the poison from the scorpion sting may return within the hour as he leaves their home.