Des machines imitatives et des machines théatrales
A French technical treatise by J.-A. Borgnis, published by Bachelier in 1820, on imitative and theatrical machines for the stage. The pictures are engraved cross-section plans of stage mechanisms, with cut-away walls, pits and sliding panels labelled with letters. A designer could take from them the clean hatched rendering of earth, rock and masonry used in period engineering drawings.
