History of the Soroban

Dust Abacus

The original utilization of an abacus-related calculation system is presumed to have been in the form of a board covered with dust or fine sand. The sand was divided into lines, each one representing a different numerical position. Numbers and quantities were calculated by means of various signs drawn along the lines. The early civilization of Mesopotamia may have seen the development of such a rudimentary calculator.

Line Abacus

With time, the dust abacus developed into a ruled board on which pebbles or counters were placed on lines somewhat like checkers on a backgammon board. Its wide use in Egypt, Rome, Greece, India, and other ancient civilizations is well attested. Herodotus (484-425 BC) most likely refers to a line abacus in his record: "The Egyptians move their hand from right to left in calculations, while the Greeks from left to right." A famous example of the line abacus is the Salamis Abacus preserved at the Athens Museum. It consists of a white marble board (149 by 75 centimeters) with lines drawn on it.

Grooved Abacus

In addition to the line abacus, the Romans made use of a more advanced design. Several grooves were carved into the board along which counters were moved up and down. One counter was laid in each of the upper grooves, while four in each of the lower grooves. Some additional counters were laid on the right to facilitate the calculation of fractions.
Roman Grooved Abacus

Ancient Chinese Abacus

The early Chinese abacus was very similar to the ancient Roman grooved abacus. The picture below represents the ancient Chinese abacus imagined from a description given in a book titled Mathematical Treatises by Ancients written by Hsu Yo towards the end of the Later Han Dynasty, about 1700 years ago, and annotated by Chen Luan some 300 years later.

This abacus is closely similar to the Roman grooved abacus both in construction and in the method of calculation. It may well be assumed that the Roman grooved abacus was introduced to China in earlier days.

Chinese Abacus

In China, the abacus came into common use during the Ming Dynasty. A book titled Ch' o Ching Lu gives this proverbial expression: "A servant, some time after he is hired, comes to do nothing more than he is ordered to. Therefore, he is like an abacus counter." A book written by Wu Ching-Hsin-Min in 1450 gives descriptions of the abacus. A large number of books published towards the end of the Ming Dynasty attest to the fact that the abacus had come into popular use. The abacus then had two counters above the bar and five below. This type of abacus is still being used in China these days.
Ancient Chinese Abacus

Soroban (Japanese Abacus)

A little past the middle of the fifteenth century, the Chinese abacus and its operational technique were introduced to Japan. Shortly afterward, Japan entered a long period of peace, which fostered the development of her cities and commerce. Mathematicians' constant and diligent study developed a distinct Japanese method of the soroban operation different from the original Chinese method. The large-sized Chinese abacus was improved into a handier smaller-sized one. Towards the end of the nineteenth century, the soroban with one five-unit counter and four one-unit counters on each rod came into use along with the older type which had one five-unit counter and five one- unit counters on each rod. In 1938, the technique of the soroban operation was included in the national grade-school textbooks on arithmetic compiled by the Education Ministry. Today, the soroban technique is a required study in the third and upper grades. The soroban with one five-unit counter and four one-unit counters on each rod is the standard nowadays. It should also be noted that the older Chinese division method, which makes use of the cumbersome division table, was formerly replaced by the Japanese division method, which makes use of the multiplication table. The inclusion of the soroban technique in the curriculum of Japanese compulsory education and the enforcement of the soroban efficiency tests system since its inception in 1928 have been the two major factors which have led to the present popularity of soroban in Japan.

Japanese Abacus
(used till the 19th century)
Abacus (Soroban)
for foreigner's use
Current Abacus (Soroban)
in Japan