They are very small, fitting in the palm of your hand. A few hand abacuses from this time have been found. There is evidence that people were using abacuses in ancient Rome (753 b.c.e. Drawings of people using counting boards have been found dating back to the same time period. It was used by the Babylonians around 300 b.c.e. It was found on the island of Salamis, a Greek island, in 1899. The oldest counting board that has been found is called the Salamis Tablet. Since counting boards were often made from materials that deteriorated over time, few of them have been found. These evolved into actual tables with grooves in them to move the counters. The earliest counting tables or boards may simply have been lines drawn in the sand. Often they were simply boards or tables on which pebbles or stones could be moved to show addition or subtraction. It is taken from the Greek word abax, which means "flat surface." The predecessors to the abacus -counting boards - were just that: flat surfaces. Addition and subtraction can easily be performed by moving beads along the wires of the abacus. Each bead represents a number, usually 1 or 5, and can be moved along the rods. Each rod represents a different place value -ones, tens, hundreds, thousands, and so on. An abacus consists of a wooden frame, rods, and beads. It has endured over time and is still in use in some countries. The abacus is the most ancient calculating device known.
0 kommentar(er)
