systems. As decimal fractions may be learned much easier than vulgar, and are more simple, useful, and necessary, and soonest wanted in more useful branches of Arithmetic, they ought to be learned first, and Vulgar Fractions omitted, until further progress in the science shall make them necessary. It may be well to obtain a general idea of them, and to attend to two or three easy problems therein: after which, the scholar may learn decimals, which will be necessary in the reduction of currencies, computing interst, and many other branches. Besides, to obtain a thorough knowledge of Vulgar Fractions, is generally a task too hard for young scholars who have made no further progress in Arithmetic than Reduction, and often discourages them. I have therefore placed a few problems in Fractions, according to the method above hinted; and after going •through the principal mercantile rules, have treated upon Vulgar Fractions at large, the scholar being now capable of going through them with advantage and ease. In Simple Interest, in Federal Money, I have given several new and concise rules; some of which are particularly designed for the use of the compting-house. The Appendix contains a variety of rules for casting Interest, Kebate, &c. together with a number of the most easy and useful problems, for measuring superficies and solids, examples of forms commonly used in transacting business, useful tables, &c. which are designed as aids in the common business of life. Perfect accuracy, in a work of this nature, can hardly be expected; errors of the press, or perhaps of the author, may have escaped correction. If any such are pointad out, it will be considered as a mark of friendship and favor, by The public's most humble and obedient Servant, NATHAN DABOLL. 89, 93 of Currencies, do. of Coin for finding the contents of Superfices & Solids 220 to reduce the currencies of the different Rebate, A short method of finding the, of any giv showing the number of days from any day of one month, to the same day in any other showing the amount of 17. or 1 dollar, at 5 & 6 per cent. Compound Interest, for 20 years shewing the amount of 1. annuity, forborne showing the present worth of il. annuity, for 31 yrs. at 5 & 6 per c. Compound Interest of cents, answering to the currencies of the United States, with Sterling, &c. Weights of several pieces of English, Portuguse, & DABOLL'S SCHOOLMASTER'S ASSISTANT. ARITHMETICAL TABLES. Numeration Table. Pence Table. 8 7 Hundreds of Millions. Tens of Millions. Millions. Hundreds of Thousands Tens of Thousands Thousands. 5 6 5 4 3 1 6 Fed bu. This measure is applied to grain, beans, flaxseed, salt, eats, oysters, coal, &c. 1619432 80 83 96 81 | 90|99|108 40; 48 56¦ 64 72 18278648|54|69|72 | 20 30 40 50 60 70 80 901 100110120 99|110|181182 35 144 | 55 | 66 | 77 ¦ 83 2186 | 48 | 60 | 72 | 84 | 50 | 108 | 120|335|144 rera this Table: Find your multiplier in the left 4 20 235 ib |