Tom devises lots of weird, literary-based strategies to help Jim escape for he wants the escape to be as grand as one of those carried out in the romantic books he likes to read.
One of his plans includes a rope ladder and a shirt on which Jim can keep a journal. Huck steals some supplies (shirt, sheet) from the Phelpses. He tries to call it "borrowing," but Tom, who apparently is now all morals, tells him that, in fact, it's stealing.
But after first resisting it, Tom later concedes that the stealing is okay, since everyone knows prisoners get a free pass to steal what they need.
The story where liberating Jim is told is found in Chapter 35. Get summary and analysis for this chapter from the following links below:
Cliffsnotes.com
Shmoop.com
Litcharts.com
Sparknotes.com
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