The exercises become more difficult, developing greater and greater skills until Ruskin feels his reader is ready for watercolors and finally composition, which he treats in detail as to the laws of principality, repetition, continuity, curvature, radiation, contrast, interchange, consistency, and harmony. All along the way, Ruskin explains, in plain, clear language, the artistic and craftsmanlike reasons behind his practical advice — underlying which, of course, is Ruskin's brilliant philosophy of honest, naturally observed art which has so much affected our aesthetic. Three full-page plates and 48 woodcuts and diagrams (the latter from drawings by the author) show the student what the text describes. An appendix devotes many pages to the art works which may be studied with profit.