Idea rationaria, or The perfect accomptant, necessary for all merchants and trafficquers; containing the true forme of Book-keeping, according to the Italian methode: wherein is first, the introduction to the forme, 244. queries and answers, with instructions how to ballance the leger, two waste-books transported in two journals, out of which are transported 2. legers both ballanced. After which followes A moneth-book, invoys-book, factor-book, specie or cash-book; instructions how to keep a book of petty-charges or pocket book. By Robert Colinson