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.
Transverse Joint occurs when the fibres of one of the pieces joined are at right angles to those of the other. It may be either horizontal, as between a trimmer and trimming joist, etc, or perpendicular, as when posts, studs, puncheons, or quarters, etc, are connected with beams, plates, curbs, sills, etc.
In log huts the joints between the logs are made water-tight by filling in with clay, twigs, etc, and lining the inside with laths or boards ; or simply packing the joints and plastering with clay will suffice. Joints between planks are rendered impervious to water by caulking them, as already explained under Caulked Joint.
Wedged Joint is one tightened up or secured by a wedge, which is a triangular prism having two planes meeting at a more or less acute angle, and forming what is generally known as the cutting edge. In carpentry, however, this edge is not required to be fine, but in joinery it is often all the better for being so. In driving wedges extreme caution is necessary, since the percussive action of the hammer so vibrates the particles of the body into which the wedge is being forced that every facility is afforded for its gradual penetration, which must end in splitting the body through the forcible separation of the opposite surfaces it slides against, unless stopped in time, or checked by a cramp or strap strong enough to turn the tables and bruise or cripple the fibres of the wedge, so as to destroy its elasticity and prevent it from swelling or recovering its size and shape after the removal of the confining ligature. In lengthening timbers by scarfing, folding wedges are much used, and they are as often as not called keys. Trimmers for carrying landings, and bearers for supporting winders, are firmly wedged to the wall. For tightening the cords of scaffolding, easing centerings, striking concrete platforms, etc, one or more wedges become necessary, as is likewise the case in many other departments of the carpenter's work, examples of which may be instanced in caulked joint, dovetail joint, fox wedged joint, etc.