I have a slightly different last verse with an additional line ...

Sharks all sang the chorus and said 'while in the brine
Ragtime ditties bore us but by gum, this is fine'
They spluttered with their S's until they got lockjaw
And Sammy left them singing as he climbed on board ...

(and yes, Joe Clone, the last line of the previous verse is complete. It makes more sense when you carry on into the chorus!)

Hope that helps

Helen.