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number of days in each month may be very easily remembered by recollecting, that the first seven are long and short alternately; and again the remaining five, long and short alalternately. And taking them in numerical order, they are— 1, 3, 5, 7, long ; 2, 4, 6, short; 8, 10, 12, long, and 9, 11, short. The short months, with the exception of the second or February, being each 30 days, and the long 31 days each.*

Leap year may be known by dividing the numbers expressed by the two last figures, in the number of the year, according to the Christian era, by 4: if there is no remainder, it is leap year; otherwise the remainder shows how many years it is after leap year. To this there are the exceptions respecting the centuries before noticed.

Jr. p H JP D H. M. See Prs D H M Sec 1. 3 6.20 2. 7 5 21 54 47 3. 26 142 16 14, 20 4 5 23 3 5 16 20 21 42 176 14 20 10 6 3 19 2 4 14 29 27 72 196 20 17 34 4 6 15 5 3 18 27 59 80 160 17 35 12 3 4 21 4 6 20 44 51 64 221 15 43 49 5 5 18 9 323 57 53 55 143 19 51 42 MOTION.

60 Thirds (”). . . . . . . . make ... . . . . . . One Second...." 60 Seconds. . . . . . . . . . . . . . . . . . . . . . . . . . One Minute....' `66, Minutes. . . . . . . . . . . . . ... • - - - - - - - - - ... One Degree.... • 30 Degrees. . . . . . . . . . . . . . . . . ... ...... One Sign...... S 12 Signs. . . . . . . . . . . . . . . . . . . . . . . . . . . . One Great Circle.

This table is used in Astronomical and Geographical calculations. Examples of Addition are not necessary.

* In mercantile transaetions, numerically reckoning the months has some advantages. If I have a bill passed, suppose in January, payable 3 months after date, January being the first month, 1 add thereto the number of months, the bill has to run, and instantly discover it will be due or payable in the 4th wionth, without the necessity of seperately counthong the months.

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SUBTRACTION DIVERS DENOMINATIONS

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COMPOUND SUBTRACTION.

PLACE the numbers to be subtracted under each other, as before directed in Addition, and place the greatest uppermost.

Begin at the right hand, and subtract each number in the lower line, from that above it, and write down the several remainders." - -

When the lower number is greater than that above it, subtract it from as many as make one of the next higher denomination, to the remainder add the upper number, and the sum will be the whole remainder, carry this one which was borrowed to the number of the next denomination, which subtract as before, and thus proceed to the highest, which subtract as in whole numbers.

... When the number in the lower line is equal to that above it, write a cipher in the remainder, unless the figure or figures in the next lower denomination, already subtracted, was or were greater than the figure or figures in the top line imme*iately aboveit, in which case one more should be subtracted.*

If there are an equal number of farthings, or other parts annexed to the lowest denomination, the cipher is always. to be omitted.

The method of proof is the same as in simple subtraction.

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Hence, the reason of borrowing, both in simple and o numbers, plainly appears, and the same method may be easily applied.to other compound quantities. - -

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1. From 12 10 3 2. From 4 1 1 0 3. From 4 1 1 0 Take 7 8 1 Take 2 16 10} Take 1 14 1+

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7. From 19 0 14 8. From 12 10 3 9. From 12 10 3 Take 17 3 25 Take 9 13 4+ Take 2 16 10}

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10. From 17 11 14 11. From 8 12 6: 12. From 15 12 44 Take 13 17 84 Take 5 194} Take 11 17 84

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13. From 18 16.1# 14. From 100 0015. From 100 0 0 Take 13 123%. Take # , Take 99 19 113

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16. From 20 0 0 17. From 200 0 18. From 45 12 4 Take 11 4} Take 19 8 7+ Take 19 0 10%

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&. d. 19. From 45 12 4, 20. From 27 11 83 21. From 47 10 64 Take 26 11 5%. Take 16 109, Take 18 12 9

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22. From 44 18 14 23. From 417 1313 34. From 247 17 s Take: 37 1810# Take 329 158 Take 148 199

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25. From 450 74.26. Borrowed 247 164. 27. Lent 36 12 04 Take 19810; Paid 168 1873 Recd 14 0 11:

28. Bor. 36 12 0# 29. Lent 273 126; 30. Bor. 250 06 Paid, 14 0.11% Recd 195 4 74 Paid 197 1584

31. From 436 00; 32. From 73 00; 33. From 1247 10.4% Take 379 1254 Take 1800; Take 84 187;

34, Bor. 1675 00, 35. Lent 475 00, 36. From 754 84 Paid 896 3.5% Recd289 0 64 Take 696 2.9%

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37. Ber. 170 0-0 38. Lent 113 15 0 39. From 896 II 63 Paid 1342 6 Recd, 85 1764 Take 98-1694 --- —

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44. From 14 17 21 45. From 11 16 1446. From 7 11 14 19

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47. From 12 102.21 48. From 11 8 1620 49.From 178 412 Take 7 80 19 Take 8 10 1923 Take 119 1715

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