Counting Rods - History

History

Counting rods were used by ancient Chinese for more than two thousand years. In 1954, forty-odd counting rods of the Warring States Period were found in Zuǒjiāgōngshān (左家公山) Chǔ Grave No.15 in Changsha, Hunan.

In 1973, archeologists unearthed a number of wood scripts from a Han dynasty tomb in Hubei, one of the wooden script written:“当利二月定算”,this is one of the earliest examples of using counting rod numeral in writing.

In 1976, a bundle of West Han counting rods made of bones in was unearthed from Qian yang county in Shanxi The use of counting rods must predate it; the Laozi, a text originating from the Warring States, said "a good calculator doesn't use counting rods." The Book of Han recorded: "they calculate with bamboo, diameter one fen, length six cun, arranged into a hexagonal bundle of two hundred seventy one pieces.". At first the cross section of calculating rod is round, by Sui dynasty, triangular rods were used to represent positive number,rectangular rods for negative numbers.

After the abacus flourished, counting rods were abandoned except in Japan, where rod numerals developed into symbolic notation for algebra.

Read more about this topic:  Counting Rods

Famous quotes containing the word history:

    I am ashamed to see what a shallow village tale our so-called History is. How many times must we say Rome, and Paris, and Constantinople! What does Rome know of rat and lizard? What are Olympiads and Consulates to these neighboring systems of being? Nay, what food or experience or succor have they for the Esquimaux seal-hunter, or the Kanaka in his canoe, for the fisherman, the stevedore, the porter?
    Ralph Waldo Emerson (1803–1882)

    The history of all hitherto existing society is the history of class struggles.
    Karl Marx (1818–1883)

    Revolutions are the periods of history when individuals count most.
    Norman Mailer (b. 1923)