The arte of vulgar arithmeticke, both in integers and fractions

devided into two bookes: whereof the first is called Nomodidactus numerorum, and the second Portus proportionum ... whereunto is added a third booke, entituled Musa mercatorum: comprehending all the most necessarie and profitable rules used in the trade of merchandise : in all which three bookes: the rules, precepts, and maxims, are not onely composed in meeter for the better retaining of them in memorie, but also the operations, examples, demonstrations, and questions, are in most easie wise expounded and explaned, in the forme of a dialogue, for the readers more deere understanding ... newly collected, digested, and in some part devised by a welwiller to the mathematicals