Five-bead abacus, old abacus, soroban, 4 units, Showa retro

#Macchan's Retro, Rare, and Hard-to-Find Items
#Macchan's Ornament Series
#Macchan's Household Goods Series

This was found in my grandfather's house. It's quite old, so I'm listing it as a Showa retro item rather than for practical use! Please only purchase if you understand that this is a used item!

Size: Approximately 33cm width x 10cm height

~Information from the internet~
This information was researched online solely to describe the product. Everything shown in the photos is included. As I am an amateur, there may be errors in the information, so please research it yourself and purchase only after you are satisfied.
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Four valuable old abacuses (soroban) with various shapes and historical features are lined up. By paying attention to the number and shape of the beads on each abacus, you can see historical changes and characteristics. Features and Historical Background of Abacuses Five-bead abacus (5 lower beads) The photo includes abacuses where there are 5 beads below the beam (middle divider).

This is characteristic of the go-dama soroban widely used in Japan from the Meiji to early Showa periods. It is a format that predates the current mainstream yon-dama (4 lower beads). Abacus with 2 upper beads (Chinese style) If the uppermost abacus, for example, has 2 beads above the beam and 5 beads below (ni-go-dama), it is the format of a traditional Chinese abacus (suanpan).

Shape of the beads (round and diamond-shaped beads) Beads with a rounded shape tend to be from older periods (e.g., Edo to early Meiji periods), and as time progressed, they changed to a sharper diamond shape that is easier to flick with your fingers. Inscriptions on the beam Abacuses with characters like 百 (hundred), 十 (ten), and 一 (one) engraved on the beam to indicate place value (digit) are common designs on old, practical abacuses.