Rietz by Nestler
Germany, 1920s, simplex, 25 cm scales, celluloid laminate on mahogany.
German engineer Max Rietz designed the Rietz scale system in 1902
In Europe, the term Rietz was often used for slide rules that had a few more scales than the original Mannheim rule; cube, inverted C, and trigonometric scales.
Rules with many arrangements of these scales were made for use in Europe.