... rub out any of the pencil inside the outline of the letter, retouch it, closing it up to the inked line. The straight lines of the outline are all to be ruled,[5] 15 but the curved lines are to ... of ground there is the light of the little pebbles or dust; in the darkness of foliage, the glitter of the leaves; in the darkness of flesh, transparency; in that of a stone, granulation: in ... with the fine point, removing any single speck or line that may be too black, with the point of the knife: you must not scratch the whole with the knife as you do the ink. If you find the texture...