172                       Duodecimals.

PART IV. DUODECIMALS;

OR    WHAT ARE GENERALLY CALLED

Cross-Multiplication, and Squaring of dimensions by Artificer, and Workmen.

RULES FOR MULTIPLYING DUODECIMALLY.

1,—Under the multiplicand write the corresponding denominations of the multiplier.

2.—Multiply each term in the multiplicand (beginning at the lowest) by the feet in the multiplier ; write each result under its respective term, observing to carry a unit under every 12 from each lower denomination to its next superior.

3.—In the same manner multiply the multiplicand by the primes in the multiplier, and write the result of each term one place more to the right hand of those in the multiplicand.

4.—Work in the same manner with the seconds in the multiplier, setting the result of each term two places to the right hand of those in the multiplicand, and do on for thirds, fourths, fyc.

EXAMPLES.

ft. in.    ft. in. (1) Multiply    7    9 by 3    6

Cross-Multiplication.    Practice.      Duodecimals.    Decimals. 7   9                6^79           79              7,75

3X6                               3:5        3    6                  3,5

¦21 0~0=7x3            23    3~      ~23    3     x3       3,875

•2 3 0=9x3              3 10 6         3 10 6x6     23,25

3 6 0=7x6            27    16        27    1  6         IP7J26

0 4 6=9x6

27 1  6