[SIXTEENTH LESSON.]
BOSSES, KNOBS, BARS, AND POLISHED ORNAMENTS.
There are several small effects in ornament which the carver should study with care; they are generally applicable to most kinds of decorative art. The first of these is the employment of bosses or knobs, some left plain, and some carved, hemi-spherical or less. They may be almost flat, but are always smooth at the edge and polished. They were very extensively used in early carving and metal-work, and the reader may see many illustrations of them in the works of Hulme. Sometimes the knob becomes a small spot or a mere dot, employed to introduce light into a dark ground. The practical theory is that the knob represents the plain or ornamental head of a nail used to hold the work to the wall, or the rivets of armour, which the Goths transferred from coats of mail to linen and woollen. But the real reason is to introduce points of light.
