procedure for the mathematical and geometrical experiment and device for exercising the method

摘要

Drawing board comprises along its edges guide tracks for a T-square, and along one edge a sheet clamping rail. On the guide tracks are placed cursors which protrude overthe drawing surface ans which each consist of a main body and a locking cap, between which can be clamped =1 elastic thread ends. Pref. the main body and cap of the cursor are made of resilient wear-resistant plastic material e.g. polyamide. The cursors are of simple construction, and allow more rapid easy attachment and detachment of the thread ends than in conventional drawing boards. Also, simultaneous attachment of several thread ends to the same cursor allows greater variety in the representation of geometrical figures.