Traité sur la science de l'exploitation des mines, par théorie et pratique: 1
A French treatise on mining science and practice by Christoph Traugott Delius, published in 1778 by Pierres, aimed at mine engineers and working miners. Its plates show underground workings, shafts, stairways, timber lining, and water-powered machinery drawn in fine engraved line with hatched shading. A designer might take the dense, orderly hatching and the clear plan-and-section layouts as a model for technical diagrams.
