What are character sketches of both Jimmy Wells and 'Silky' Bob in "After Twenty Years"?

'Silky' Bob and Jimmy Wells, longtime friends who have parted ways, agreed to meet again in their favorite restaurant in New York City twenty years later.

O. Henry's story begins on the appointed evening in New York City. A policeman, whose beat includes the block on which the old restaurant known as 'Big Joe' Brady's was located, notices a man standing in the unlit doorway. The man explains that he is waiting for his old friend because they made an agreement to reunite after twenty years. 

Patrolman Jimmy Wells

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  Conscientious lawman: Wells is first and foremost an officer of the law: When the man in the doorway says that he is meeting an old friend after twenty years, Jimmy realizes that this man is his old friend, Bob. But, he makes no comment because he has seen a Wanted poster with a man who resembles Bob. Therefore, he is careful not to identify himself because he wants to be certain about his friend's resemblance to the man who is wanted by the law. 
  Wells then returns to the police station, verifies Bob's identity, and asks a plain clothes policeman to make the arrest because he does not have the heart to embarrass his friend. He gives the other policeman a note of explanation for Bob.


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  Loyal friend: After Bob lights a cigar, the flame reveals the face that is on the Wanted poster, confirming Wells's fears. Because Bob has been his friend and is loyal enough to return to meet him, Wells does not have the heart to arrest his old friend. So, he says with irony, "Hope your friend comes around all right."

'Silky Bob'

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  An adventurous character: Whereas Jimmy remains true to his personality of twenty years ago, Bob has gone a different direction in life. After he went out West, Bob "kept hustling around over it pretty lively" and lost touch with Jimmy as he involves himself in various questionable adventures.


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  An unethical man: He is also not ashamed of what he has done, boasting that the West has given him everything that he has wanted. He adds, "It takes the West to put a razor-edge on [a man]." And, he refers to Jimmy as "a kind of plodder, though, good fellow as he was."


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  A loyal friend: Nevertheless, Bob has not forgotten the love he has had for Jimmy Wells and in an act of strong loyalty, Bob travels over a thousand miles to meet his friend despite possible risks. 


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  A man who is touched by Jimmy's act of friendship: When he reads Jimmy's note, his hand is steady at first, but it trembles after he realizes that it has been his friend with whom he has talked in the doorway. This trembling may indicate his realization that the old love that the two of them had for each other is gone as well as his being touched that Jimmy has not wanted to embarrass him.