Principes de dessin d'imitation à l'usage des établissements d'instruction publique
A French drawing manual by Alexandre Le Béalle, published in Paris by J. Delalain in 1875, written as teaching material for public schools. Its numbered plates present geometric solids and perspective constructions in fine line shading. The plates show planes, prisms, pyramids and construction lines, so a designer can use them as clean technical diagrams of how shadow and volume are built.
