Nailing (-). The side and end pieces are to be nailed, as shown by Fig. 169, three 6-penny casing nails being used at each angle. When brought together, the pieces must be flush - pretty nearly right will not do.

Nails, when seen in a certain position, appear equal in width throughout their length, A, Fig. 170; while a view at right angles to the first, shows them wedge-shaped, B, Fig. 170. In starting a nail, the line represented by a must be placed across the grain of the wood, so that the point will cut the fibers which are displaced. If the line b is placed across the grain, a few only of the fibers will be severed, and the others will be simply pressed apart by the inclined sides of the nail, an action which is quite likely to split the work.

Fig. 168

Fig. 169

Plan.

Elevation.

Fig. 170

A.

B.

150. Hammer Marks on the work must be avoided. One who is skilled in the use of a hammer, can drive a nail slightly below the surface of the work without leaving a scar; but it is better to stop driving before the hammer head touches the work than to risk damage.