New Allbrit Planimeter by Stanley With Instruction Manual

This almost new Planimeter is a Polar type integrating machine that was made in England to calculate the area of closed irregular shapes. This Planimeter contains three parts: 1) a pole weight with steel pin that acts as a steady pivot. 2) A sliding tracer arm with a pointer and handle. 3) A carriage with measuring wheels. 4) A magnifying glass and calibration bar. The pole weight is connected via a hinge to the carriage. Moving the tracer pointer along the borders of the shape will cause the carriage wheel to rotate. The net roll of the wheel is proportional to the area of the shape and can be read from the calibrated scale. The Planimeter is numbered 24604 and comes with its original bakelite box. A calibration table is glued to the inside lid. Both the pole weight and box are marked Made in England. A 12 page instruction manual is included.