Further points used to sustain the idea of a murder are the captain 's refusal to land elsewhere , his slow sailing , his administration of the emetic in secrecy .
That he did n't return to Buenos Aires with the ship .
Further points used to sustain the idea of a murder are the captain 's refusal to land elsewhere , his slow sailing , his administration of the emetic in secrecy , and that he did n't return to Buenos Aires with the ship .