Traders have always needed counting boards of some kind. The earliest versions, which predated the abacus, would have been used by traders at markets. Traders drew lines in the sand with their fingers or a stylus of some kind. They would then place pebbles between those lines to represent numbers.
The Abacus – or counting frame – evolved from ancient times, through to the Middle Ages and Modern Times. In 500 BC the early counting boards included The Salamis Tablet, the Roman Calculi and the hand-abacus. The Roman hand abacus was often made from stone and metal.
In the Middle Ages came the Apices, the coin-board, and the line-board, which date from 5 AD to around 1,400 AD.
Most were made from wood, and originally the beads on which you counted ran vertically. By the time the system had evolved to line-boards, the columns ran horizontally.
From 1,200 AD the abacus evolved into the Chinese suan-pan, the Japanese soroban, and the Russian schoty. The classic Chinese abacus is the one we are most familiar with. It has two beads on the upper deck and 5 on the lower deck, and is often called the ‘2/5’ abacus. From about 1850 this was replaced with the ‘1/5’ abacus, with one bead on the top deck and five beads on the bottom deck.
The Chinese abacus was further adapted by Lee Kai-Chen, and by 1958 the ‘new’ abacus could be found in use, complete with an instruction book. It has more decks top and bottom combining the ‘1/4’ soroban model and the ‘2/5’ suan-pan style. Kai-Chen said it was a “Revolution of Chinese Calculators”.
Contribution to Retail History
The abacus, or beads on a board, provided an easier and more sophisticated retail transaction methodology and was actually the bridge from pebbles, twigs and lines in the sand to the first calculator. The abacus simplified the mathematical process for merchants and traders and was used for about 3,600 years until the first mechanical calculator appeared in 1642.