Related Clues:

• The solitary seaman might retire into his shell
• A seaman, all by himself, may retire into his shell
• Might the seaman by himself be the equal of Shelley, perhaps, by the sound of it?
• The sort of seafood that the seaman got all by himself
• Might the graduate turn up and come out of his shell all by himself?
• AB retired into his shell for solitary
• You might need a pin for that Shelley friend of Pickwick
• You might stick a pin into this member of the Pickwick Club
• How one might get a blow in for Shelley?
• Sounds like the way Shelley, perhaps, might close his eye to the French
• A graduate by himself does not come out of his shell
• Shelley, by the sound of it, in Pickwick
• Shell needs us, by the sound of it, to be awake
• Source of iridescent buttons
• See 21