Tina's Abaci

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Small Abacus purchased in Dezful Bazaar, Iran

Suanpan Abacus Paperweight

Lotus Flower Suanpan modified for the addition of Yards, Feet, Inches, Eighths, Thirty-Secondths and One Hundred and Twenty-Eighths, made in China, modified in Britain

Lotus Flower Suanpan modified for the addition of Days, Hours, Minutes and Seconds, made in China, modified in Britain

Lotus Flower Suanpan modified for the addition of Degrees, Minutes, Seconds and Decimal Fractions of a Second, made in China, modified in Britain

Lotus Flower Suanpan modified for the addition of Long Tons, Hundredweights, Stones, Pounds,Ounces and Drachms. Ounces and Drachms are base 16 and the remaining four rods after this are for base 16 arithmetic, made in China, modified in Britain

Lotus Flower Suanpan with 11 Rods made in The People's Republic of China

Suanpan with 13 Rods

Suanpan with 9 Rods packaged with Jesse Dilson's book entitled "Abacus"

Red Lion Suanpan with 11 Rods made in China

Decorative Suanpan

Functional Child's Suanpan, Made in China by the Galaxy Stationery Co, Ltd.

Soroban with 21 Rods

Narasaki Soroban 27 Rods

Sharp Elsimate EL-428

Sharp Elsimate EL-8048

Soroban with reset button 13 Rods

Soroban 9 Rods

Soroban 11 Rods

Cranmer Abacus for the Blind. The felt surface underneath the beads prevents them from moving accidentally.

Soroban Style Abacus made using K'Nex

Roman Abacus made using K'Nex. The rods are labelled at the top from the left, XMM = 10 million, MM = 1 million, CM = 100,000, XM = 10,000, M = 1,000, C = 100, X = 10 and I = units, used for decimal calculation in the manner of a soroban. The rod labelled theta counts 12 Uncia which is 1/12th of a Roman foot. The remaining three symbols are still subject to debate but are most likely, from top to bottom, the Semuncia = 1/24 or half an Uncia, the Sicilicus = 1/48 or half a Semuncia and the Sextula = 1/72 or one sixth of an Uncia. This all fits with the soroban style operation of this abacus except for the Sextilus rod, labelled 2. I therefore propose a more logical option which fits with the overall soroban style that each bead on this final column represents 1/144th of an Uncia, the Dimidia Uncia. In this case three Dimidia Uncia equals one Sicilicus, two Sicilici equal one Semuncia and two Semuncia equals one Uncia. In this way the abacus becomes self consistent.

Duplex Abacus, Decimal on one side and Binary on the other. The Binary Abacus shows the sum 101(5) Times 1101(13) equals 1000001(65) made using K'Nex

Pocket Decimal Abacus with 7 rods made using K'Nex

Japanese Soroban with five beads on Earth and one in Heaven, of a type superceded in the 1930's by those with four beads on Earth and one in Heaven shown above

Soroban with five beads on Earth, one in Heaven and 27 Rows.

Childs Abacus in a pencil box. The dividers on the upper abacus have been added by me to allow temporary modification for different bases

Pencil Box Abacus.

Abacus Style Calendar showing November 3rd 2010

Schioty with a quarter Rouble Rod, the line of four beads four rows from the bottom and a rod at the bottom for counting the Den'gi (1/2 Copeck) and the Polushka (1/4 Copeck). The Rouble is the currency of Russia with one Rouble equal to 100 Copecks

Schioty, 17cm x 11cm. Donated by Alla Shuvalova, Novocheboksarsk, Russia



Small but Colourful Schioty from Lithuania.

Decimal Schioty

Child's Schioty

This Abacus was obtained from Hong kong. It is very similar in design to the decimal schioty but with nine beads to a line instead of ten. It does for the Schioty that which the Soroban does for the Suanpan.

Homemade Table Abacus based on the Exchequer Table in Strasbourg Museum. The sum is VII(7) Times DCXXXII(632) Equals MMMMCCCCXXIIII(4424) or MMMMCDXXIV

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