“It was Albrecht Dürer and Leonardo da Vinci who (for the western world, at least), determined the proportions of the human physique and the dimensions of the natural world that such a physique might inhabit. Dürer composed several illustrated works of artistic theory in his last years, the summation of a life devoted to the exact representation of natural objects. Instruction in Measurement (1525) dealt with the application of geometry to works of art, decorative and fine, covering a multitude of subjects to which mathematical analysis might be applied: cones, polygons, pyramids, letterforms, and above all, perspective. This Octavo Digital Facsimile reproduces the posthumous, but first complete, edition (1538), which includes additional woodcuts and corrections to the text derived from Dürer+s working copy.”