"'How's the bonny blade?' said Nick"

Portrait of Dr Samuel Johnson
Public DomainPortrait of Dr Samuel Johnson - Credit: Joshua Reynolds
Nick is quoting from the poem by Dr Johnson which begins 'Long-expected one and twenty', previously referred to by Gerald Fedden (see bookmark for p.67):

                                                      When the bonny blade carouses,

                                                      Pockets full, and spirits high -

                                                      What are acres? What are houses?

                                                      Only dirt, or wet and dry.


Here blade means dashing young man, and Nick is, of course, referring to Toby.