A slide, that can be set in eight different positions on the cylinder, carries eight figured rings that can be set to represent eight or any smaller number of decimal places. Each turn of the crank adds the number set up on the rings to the number represented on the ten recording wheels carried by the lower shaft. The multiplication process will best be understood by an example. The cylinder is then turned twice to multiply by the units figure of the multiplier. A half-turn of the crank backward erases this result, bringing all the wheels to 0, ready for the next operation.
Division is the reverse of multiplication.
The dividend is set up on the wheels, the divisor on the rings, and the quotient records itself on the upper recording wheels.