WEEMS & PLATH Parallel Rolling Plotter
This popular instrument consists of a plotter mounted on a roller, and includes a semi-circular protractor for measuring courses and bearings against a meridian. It also includes two quarter-circle protractors for measuring courses and bearings against a parallel of latitude. Lines are transferred and kept parallel by two rollers mounted on a slide axis. Contains 1:80,000, 1:40,000, and 1:20,000 distance scales and an inch scale. Easy to use and very accurate. 12-1/4"L.