PITTSBURGH, Nov. 1807.

HAVING purchased the Copy-right of Walsh's New System of Mercantile Arithmetic, and being desirous of extending its circulation, I have just published an edition of the work, and hope, from its acknowledged utility, that our Schoolmasters and Merchants will give me all the encouragement which they may think I deserve from the nature of the undertaking.-I can further say, that I am enabled to make sales at a price lower than the same book sells in Philadelphia, either wholesale or retail; thus saving something in the price of a valuable school-book, and the carriage, besides the advantages which must always arise from manufacturing at home articles of our own consumption. ZADOK CRAMER.

MR. BLUNT's CERTIFICATE.

Pittsburgh, Nov. 2d, 1807.

THIS may certify that Zadok Cramer, Printer, has the exclusive privilege of printing and selling Walsh's Mercantile Arithmetic throughout the country West of the Alleghany Mountains, including New Orleans and all the country south.

EDM. M. BLUNT.

EXPLANATION

OF THE CHARACTERS USED IN THIS WORK.

SIGNIFIES equality, or equal to as, 20 shillings-one pound that is, 20 shillings are

Signifies more, or Addition :
added to 6 is equal to 12.

equal to 1 pound.

as 6612, that is 6

Signifies less, or Subtraction: as, 6-2=4, that is, 6 less 2 is equal to 4.

X Signifies Multiplication: as, 6X2=12, that is, 6 mul tiplied by 2 is equal to 12.

Signifies Division as 62=3, that is, 6 divided by 2 is equal to 3.

Division is sometimes expressed by placing the numbers like a fraction, the upper figure being the dividend, and the lower the divisor: thus, 49, that is, 54 divided by 6 is equal to 9.

: Proportion: as, 3:6::9:18, that is, as three is to so is 9 to 18.

Prefixed to any number signifies that the square root of that number is required.

MERCANTILE ARITHMETIC.

ARITHMETIC is the art of computing by numbers,

and has five principal rules for this purpose, viz. Numeration, Addition, Subtraction, Multiplication, and Division.

NUMERATION

Teacheth to express any proposed number by these ten characters, 0. 1. 2. 3. 4. 5. 6. 7. 8. 9.-0 is called a cypher, and the rest figures or digits. The relative value of which depends upon the place they stand in, when joined together, beginning at the right hand as in the following

Though the table consists of only nine places, yet it may be extended to more places at pleasure; as, after hundreds of millions, read thousands of millions, ten thousands of millions, hundred thousands of millions, then millions of millions, &c.

TO WRITE NUMBERS.

RULE. Write down the figures as their values are expressed, and supply any deficiency in the order with cyphers.

B