A sketch of the "Pavodilos" rebated joint as used in floor boards prepared for secret nailing is shown by Fig. 1. It is patented, and the name is registered as a trade mark by the manufacturer of the joint. "Pavodilos" jointed flooring and matching is, however, turned out by other firms who work under licence; and some specimens are worked as shown by Fig. 2, which, although the second key is lost, may possibly be preferred on account of the danger, when nailing down the flooring jointed as in Fig. 1, of damaging the feather-edge of the board that is being fixed.