EXAMINATION ESSENTIALS. ARITHMETICAL TABLES. A thorough knowledge of the following Tables is absolutely indispensable. 28 Pounds 1 Quarter TROY. For Gold, Silver, and Jewellery, and in Philosophical Experiments. 24 Grains make 1 Pennyweight(dwt) 20 Pennyweights 1 Ounce 4 Quarters 112 lbs 1 Hundred-weight 12 Ounces 20 Hundred-weight 1 Ton APOTHECARIES. [cwt. The lb. Av. contains 7000 grs. Troy. 5 Yards 1 Yard 1 Fathom 1 Rod, Pole, or 1 Furlong 1 League 1 Quarter 1 Ell Cloth M. ARITHMETIC. Arithmetic is the science which treats of numbers :of the mode of expressing them-of the manner of computing by them-and of the various uses to which they are applied in the practical business of life. Numeration is the art of expressing any number in words. Notation is the art of expressing any number by figures. . All numbers are expressed by the ten following figures :1. 2. 3. 4. 5. 6. 7. 8.9.0. The cipher or zero has no value of itself: the other nine are called digits. Every figure has two values, a single value, when it stands by itself, and a local value from the position it holds among other figures. The number one is called unity. An integer or whole number is a collection of ones, unities, or units. An abstract number denotes a number of things in general, without application to any particular subject, as 8. A concrete number denotes any particular thing, as 6 pounds, 4 feet. A prime number is that which cannot be produced by the multiplication of two other numbers, as 19. A composite number is the product of two numbers as 24, which is the product of 3 and 8. Those numbers which, when multiplied together, produce a composite, are called factors. A figure standing by itself, or on the right hand of other figures, has its own proper value, expressing so many units. A figure standing in the second place from the right expresses so many tens of units; in the third place, so many tens of tens, or hundreds of units; in the fourth place, so many tens of hundreds, or thousands of units, &c. according to the |