This section is from the book "A Practical Treatise On The Joints Made And Used By Builders", by Wyvill J. Christy. Also available from Amazon: Practical treatise on the joints made and used by builders.
This is an efficient joint for flooring, and is quickly made by taking a shallow and similar rebate out of the lower edges of the floor boards and inserting in the recesses so formed a long strip or fillet of fir, or harder wood if preferred, as represented in Fig. 129, cut and wrought to fit them, whereby open joints are prevented when shrinkage sets in. Rebated and Mitred Joint is a combination of the rebate and mitre, suitable for boards of different thicknesses, the mitre being continued only a short distance within the arris. It is similar to the joint shown in Fig. 119.
This is made by combining a groove and tongue with a rebate, as shown in Fig. 130, but it is perhaps better known under its alternative name of grooved and rebated joint. The opening of the joint resulting from shrinkage is completely covered, and if used for flooring, the nails can be concealed by edge-nailing instead of face-nailing, that is, by driving the nails obliquely through the edges before laying the next board instead of driving them straight through the face into the joist at each crossing, as is commonly done with square-edged boards.
Rounded Joint is one formed by taking off the arris, as, for instance, at a mitre, and rounding off the edge to a surface more or less cylindrical.
A hinged or movable joint given sometimes to window shutters, but most frequently seen in tables and other productions of the cabinet maker. Fig. 131 represents the joint when open, and Fig. 132 when closed.
Running Joint occurs between surfaces of which one is intended to move or slide on the other, called a runner. Friction, of which there are two sorts, enters into the consideration of this joint. One sort resists the commencement of motion, and may often be overcome by a slight jar. The other is a uniformly retarding force, and is proportional to the weight or pressure and independent of the extent of surface in contact. It is, therefore, often inconsiderable between planed surfaces in light pieces of joinery, but when troublesome may be much diminished by rubbing a little dry plumbago on the runner. If this kind of friction exists between metal surfaces, clarified oil should be mixed with the plumbago.