Principes scientifiques des beaux-arts, essais et fragments de théorie
A French translation of essays by Ernst Brücke and Hermann von Helmholtz, published in Paris in 1878, that applies optics and geometry to painting and the rules of perspective. Its pictures are plain line diagrams of geometric construction, with labelled points, dashed sight lines and converging rays, set in the textbook style of the period, which a designer could use as clear references for vanishing-point layouts and projected space.
