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design of this work is to furnish the sehools of the United States with a methodical and comprehensive system of Practical Arithmetic, in which I have endeavoured, through the whole, to have the rules as concise and familiar, as the nature of the subject will permit.
During the long period which I have devoted to the instruction of youth in Arithmetic, I have made use of various systems which have just claims to scientific merit; but the authors apy ear to have been deficient in an important point-the practical teacher's experience. They have been too sparing of examples, especially in the first rudiments; in consequence of which, the young pupil.is hurried through the ground rules too fast for his capacity. This objection I lave endeavoured to obviate in the following treatise.
In teaching the first rules, I have found it best to encourage the attention of scholars by a variety of easy and familiar questions, which might serve to strengthen their Ininds as their studies grow inore arduous.
The rules are arranged in such order as to introduce the most simple and necessary parts, previous to those which are more abstruse and difficult.
To enter into a detail of the whole work would be tedious; I shall therefore notice only a few particulars, and refer the reader to the contents.
Although the Federal Coin is purely decimal, it is so nearly allied to whole numbers, and so absolutely necespary to be understood by every one, that I have intruduced it immediately after addition of whole numbers, and also shown how to find the value of goods therein, immediately after simple multiplication; which may be of great advantage to many, who perhaps will not have an opportunity of learning fractions.
Ir the arrangement of fractions, I have taken an entire new method, the advantages and facility of which will sufficiently apologize for its not being according to other
systems. As decimal fractions may be learned much easier than valgar, 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 proviens 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 hare 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, Rebate, &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 point, ed out, it will be oonsidered as a mark of friendship and favor, by
The public's most humble
Perinutation of Quantities
for finding the contents of Superfioes & Solids 220
Hundreds of Millions.
Von Tens of Thousands.
d. 20 is ] 8 12 is 1 30 26 40 3 4 S6 S 50
4 60 5 0 60 70 5 10 72 6 80 6 8 84
96 8. 4 198 9 110
120 10 0 8
4 3 2 9 8 7 6 5 4 3 9 8 7 6 5 4 9 8 ap 6 5
gt. 98 7.6
ok. 9 8 7 4 farthings 1! bu. 9 8 12 pence," sily, salt,
920 sisilis, lo