Lot 305: A Vintage W.F. Stanley and Co. Ltd. Allbrit Compensating Polar Planimeter

This vintage precision scientific instrument is an Allbrit compensating polar planimeter, manufactured by W.F. Stanley and Co. Ltd. Designed for measuring the area of irregular plane figures on maps and plans, this example is a sliding bar model. The device is constructed from metal with a grey-painted central housing and chrome-plated components. The central body of the device is marked with the word ALLBRIT in capital letters. The sliding bar features finely engraved linear scales. The lot includes the original printed instruction booklet titled instructions for the use of the ZERO-SETTING compensating polar PLANIMETERS, which carries the maker name W. F. Stanley and Co. Ltd. along with their stylized S logo and a handwritten note reading Planimeter No 04012. The set comprises the main planimeter unit with its tracer arm and magnifying lens, a circular anchor weight, and a metal check rule. The instrument is housed in its original fitted rectangular wooden case, covered in a textured black leatherette material and lined with a pale green flocked interior. The case is secured by two silver-tone metal flip-latches and features a small white adhesive label marked 105 on the exterior.