WHEN WAS THE ABACUS INVENTED CRACK

It has eight long grooves containing up to five beads in each and eight shorter grooves having either one or no beads in each. In addition to the more common method using loose counters, several specimens have been found of a Roman abacus, shown here in reconstruction.

This system of 'counter casting' continued into the late Roman empire and in medieval Europe, and persisted in limited use into the nineteenth century. Marked lines indicated units, fives, tens etc. Later, and in medieval Europe, jetons were manufactured.

The normal method of calculation in ancient Rome, as in Greece, was by moving counters on a smooth table.

WHEN WAS THE ABACUS INVENTED CRACK

Below this crack is another group of eleven parallel lines, again divided into two sections by a line perpendicular to them, but with the semi-circle at the top of the intersection the third, sixth and ninth of these lines are marked with a cross where they intersect with the vertical line. Below these lines is a wide space with a horizontal crack dividing it. In the center of the tablet is a set of 5 parallel lines equally divided by a vertical line, capped with a semi-circle at the intersection of the bottom-most horizontal line and the single vertical line. It is a slab of white marble 149 cm long, 75 cm wide, and 4.5 cm thick, on which are 5 groups of markings. Greek abacusĪ tablet found on the Greek island Salamis in 1846 dates back to 300 B.C.E., making it the oldest counting board discovered so far. However, wall depictions of this instruments have not been discovered, casting some doubt over the extent of use of this instrument. Archaeologists have found ancient disks of various sizes that are thought to have been used as counters. The use of the abacus in ancient Egypt is mentioned by the Greek historian Herodotus, who writes that the manner of its usage by the Egyptians was opposite in direction when compared with the Greek method. Some scholars point to a character from the Babylonian cuniform which may have been derived from a representation of the abacus. However, this primitive device proved difficult to use for more complex calculations. Because abax also had the sense of 'table sprinkled with sand or dust, used for drawing geometric figures,' some linguists speculate that the Greek word may be derived from a Semitic root, ābāq (pronounced 'a-vak'), the Hebrew word for 'dust.' Though details of the transmission are obscure, it may also be derived from the Phoenician word abak, meaning 'sand.' The preferred plural of abacus is a subject of disagreement, but both abacuses and abaci are in use.īabylonians may have used the abacus for addition and subtraction. The Latin word came from abakos, the Greek genitive form of abax ('calculating-table'). The use of the word abacus dates from before 1387, when a Middle English work borrowed the word from Latin to describe a sandboard abacus. But the earliest abaci used first in Mesopotamia and later by scribes in Egypt and Greece used sexagesimal numbers represented with factors of 5, 2, 3, and 2 for each digit. China played an essential part in the development and evolution of the abacus.įrom this, a variety of abaci were developed the most popular were based on the bi-quinary system, using a combination of two bases (base-2 and base-5) to represent decimal numbers. The origin of the counter abacus with strings is obscure, but India, Mesopotamia or Egypt are seen as probable points of origin. The Babylonians used this dust abacus as early as 2400 B.C.E. Words and letters were drawn in the sand eventually numbers were added and pebbles used to aid calculations. The first abacus was most likely based on a flat stone covered with sand or dust. Just as with popular board games such as chess, shogi, and go, local, regional, and national competitions in abacus use are held for students. Although electronic calculators are replacing it for practical reasons, the use of the abacus continues to be taught in technologically advanced countries such as Japan. The abacus is a simple, inexpensive, yet powerful tool for calculation. Calculating-Table by Gregor Reisch: Margarita Philosophica, 1508

When was the abacus invented