"Not a marvedie", I think, is the phrase, meaning "not a farthing." See The Dictionary of Phrase and Fable:

Marvedie (A). A maravedi (q.v.), a small obsolete Spanish copper coin of less value than a farthing.

"What a trifling, foolish girl you are, Edith, to send me by express a letter crammed with nonsense about books and gowns, and to shde the only thing I cared a marvedie about into the postscript."- Sir W. Scott: Old Mortality, chap. xi.