Description This is a 360° protractor on a square, clear plastic base. In chartwork it can be used to plot direction from a meridian of longitude. It is most functional, however, in its use for plain paper plotting; eg. as a plotter for celestial position lines or radar targets. Larger squares, up to 300 mm, are available but are very expensive; in our experience the 120 mm version meets all normal needs. Customers for a large square could be well advised to consider the 390 mm sided Compass-rose Plotter as a very much cheaper and more utilitarian alternative. The Compass-rose Plotter has similarities in application to the Douglas square.
