A text-book on shades and shadows, and perspective
A technical drawing textbook by John Edward Hill, published in New York by John Wiley & Sons in 1900 for engineering and architecture students learning shades, shadows and perspective. The plates are line diagrams: triangles, cubes and prisms in plan and elevation, crossed by dashed projection lines, ground lines and lettered points, useful as fine-line geometric pattern and diagram scaffolding.
