The development of astronomy implies considerable progress in mathematics; it is not surprising, therefore, that the Babylonians should have invented an extremely simple method of ciphering or have discovered the convenience of the duodecimal system.
Calculations involving feet and inches are sometimes performed by means of duodecimal arithmetic; i.e., in effect, the tables of square measure and of cubic measure are amplified by the insertion of intermediate units.
The value of 7r for duodecimal arithmetic is 3+1/12+8/122+ 4/12 3 +8/12 4 +..
.; so that, marking off duodecimal fractions by commas, the area in the above case is 4 of 3, I, 8, 4, 8 X15, 3 X15, 3 sq.
Hence we see that it probably passed from the East through Greece to Etruria, and thence became the standard foot of Rome; there, though divided by the Italian duodecimal system into 12 unciae, it always maintained its original 16 digits, which are found marked on some of the foot-measures.
-- 100 feet, 66 feet or a chain of 100 links, rod, pole, or perch, measures from 10 feet to 1 foot; 18 inches; yard of 36 inches, 1/2, 1/4, 18, 1/16 yard, nail, inch, and duodecimal, decimal, and binary parts of an inch.