Praktische Anweisung zur Pastellmahlerey für Liebhaber und Mahler nach allgemeinen Regeln der Mahler- und Zeichenkunst deutlich vorgetragen
A German treatise of 1792 by Georg Christoph Guenther teaching pastel painting to amateurs and painters through general rules of painting and drawing. The pictures are hand-coloured swatch strips, each a row of rectangular pastel shades labelled with letter and number codes, showing a systematic colour-matching key a designer could adapt for palette charts or colour-coded systems.
