Suan pan is a Chinese (also used in Korea) analogue of the European Abacus. The Chinese symbol for suan, which means "calculate", reminds of "four wires held" below by the symbol for hands, and with the symbol for bamboo above the wires. As with the Japanese soroban, a bar divides the device into two regions: the heaven and the earth. Each wire, or rode, contains 5 beads in the earth region and 2 in the heavens region. One bead in each region is redundant. To my tastes, having two beads in the upper region is especially awkward. (Mote, however, that the additional beads do have their uses.) The applet below undertakes to alleviate the need to shuffle the beeds back and force.