The Useful Calculator containing the calculation of any number of yards, etc. from 60 to 133 inclusive : also a complete set of Flax Tables, on a plan entirely new. Also an Oil Table showing the quantity of oil contained, the weight being specified, to these are added, Tables showing the exchange on bills, commission or brokerage on goods, etc. from 1/8 to 5 percent. And Tables showing the amount of any salary, in come, expence, etc. by the day, week, month or year