'I have the pleasure of yours and I am glad to find, that a new Treatise of our English Coins is likely to be publish’d. I shall be always very ready to oblige Mr Willis, but yor engagement in such a Work might have procured any satisfaction my collection could afford you.' [The letter has drawings of six coins of King Henry, including a round halfpenny, all presumably in Bolton's collection, and also refers to Martin Folkes and Taylor White] (Burnett 2020b, p. 1297)