On the philosophy of painting: a theoretical and practical treatise..
Henry Twining's 1849 London treatise on painting theory and practice, published by Longman for artists and students studying perspective, light, and colour. Line diagrams map picture planes, sight lines, and lettered reference points over interiors and oak branches, alongside tonal landscape plates with figures at a fence; useful for geometric overlays, foliage outlines, and perspective schematics.
