Quote 1
But not to such extremities, or anything like them, did the present crowd come; they, for the time, being content with putting the negro fairly and discreetly to the question; among other things, asking him, had he any documentary proof, any plain paper about him, attesting that his case was not a spurious one.
"No, no, dis poor ole darkie haint none o' dem waloable papers," he wailed. (3, 24-25)
Melville tries his hand at regional dialects here and may not actually be too successful. Besides the super not-cool racial representations going on, we get a look at a particularly bleak consequence of extreme poverty: you have to live outside an accepted system or institutions.
To make him prove that he's not faking his injuries and his homelessness, the crowd asks if Guinea's got any documentation or ID to make his case. Reminder: this text is from 1857—it's not like everyone carries driver's licenses. The only people carrying the kind of documentation these people are looking for would be professionals or business owners. A very poor person straight up would not be dealing with that kind of paperwork.
This moment is especially icky because we've got a distressed man who cannot walk making money because people thought it'd be hil-ar-ious if they threw coins at him to catch in his mouth like a dog. At this point, this man is being asked—ever so politely now—if he has a doctor's note. Face palm. Talk about missing the forest for the trees when it comes to caring for your fellow man.