Square drawing frame with logarithmic markings - has individual portions with scales of different length nesting inside each other

摘要

The frame has drawing edges with scales having logarithmic divisions. It has two individual frames with straight drawing edges, giving a rectangular or square shape. The edges have scales of different length. The individual frames are of different sizes, and the external size of the smaller frame corresponds to and fits into the internal size of the larger frame. The scales on the larger frames are longer than the scales on the smaller frames.