When a beam has to be lengthened without enlarging the joint to any great extent, the pieces are scarfed together. Figs. 51-56 show a few different kinds of scarf joints as used for wall-plates, beams, and any long timbers. Many of these joints are strengthened by straps or plates of wood or iron, called fish plates, with through bolts to bind all together. Little need be said about the construction of the joints, as the annexed sketches should be sufficient guide. One of the main things to be attended to in making this, as in fact any joint, is to see that every part is an exact fit, and so ensure the strain being equally distributed.