The merchants aid: or, An help to the unskilful accomptant. : Containing certain necessary tables of value, and other things appertaining to merchanize. Composed in so short plain, and familiar a method, that he that can but make a short addition, may readily find the value of any commodity commonly bought or sold after our English accompt of weight, measure and coin. Newly calculated, approved, and set forth for the ease and benefit of all men so occupied. /