The ready reckoner, or, Trader's most useful assistant in buying and selling all sorts of commodities either wholesale or retale [electronic resource] : shewing at one view the amount or value of any number or quantity of goods or merchandise from one farthing to twenty shillings ... to which is added, 1, a double table of Portugal money ... 2, a table of expences or wages ... 3, a table of annuities and commission or brokerage ... / by Daniel Fenning