In shadowing a cylinder of considerable width, begin at the line of demarcation of light and shade, where a plane from the luminary would touch the curved surface in a straight line of contact, and having gone the whole length of this line with a tint, soften the edges with water. Proceed in the same manner the second time with a broader tint, covering the edges of the former, and washing off the edges as before, thus continually spreading each repeated tint, until you come to the line of light, viz., where a plane extended from the luminary to the axis of the cylinder, included in the plane, would cut the surface of the cylinder. Then from the opposite edge of the representation of the cylinder, lay a light tint close to the line, as narrow as it can be put on, and soften the edge of it next to the line of light ; lay a broader tint next time, and soften the edge in like man ner, next to the line of light ; proceed in this manner, until you come again in contact with the line of light ; observing, that the depth of colour in receding from the line of light in the parts which represent equal distances, should be the same, or of an equal degree. In washing towards the line of light,
the washes must be lighter and lighter, as too much colour will destroy the delicacy necessary to be preserved in the light part. If, after all, any part should appear to be too light, the defect may be made up by tinting that part only, with very little ink in the pencil. For other information, concerning the manner of preparing the tints, we shall refer to the article SHADOWING.
an edged tool, made sharp at the end, for cutting a deep incision into the wood, along a straight, edge, the edge of a square or templet, in order to enter the saw without ragging the wood. A chisel or firmer is some times used instead of the drawing-knife. In joinery, the drawing-knife is useful in rebating across the grain, cutting the shoulders of tenons, grooving across the fibres.