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386 be described in a later section. Sometimes these circular heads are built up of two thicknesses, the joint taking place in a line with the stop part of the rebate. One layer is formed of one more piece than the other, to "break joint," and the two layers are glued and screwed together as illustrated at Fig. 1263, the screws being inserted outside the line of the seen margin. This method is somewhat more economical in material and labour, as rebating out of the solid is avoided, and on this account it is more frequently adopted for ordinary work. Some leading architects, however, would not sanction this method of construction. The mouldings should be mitered, and the shoulders between the post and transom prepared; these should be loosened, glued, wedged and tightened up, cleaning off the flat surfaces and the junction of the mouldings. This will complete the frame, excepting the cornice portion of the outside part of the transom, which should be prepared and fitted in and, if desired, fixed; but sometimes it is more convenient to fix this temporarily only, so that it can be more easily scribed to the stonework after the frame is in position.

Splayed Linings. — The head part of these may be built up in sections or veneered and blocked. The method of preparing these will be fully described in the section dealing with the subject.

Framed Grounds. — The architraves being wide, the grounds are framed of strips of stuff 2 in. or more wide for stiles, and pieces 2 in. to 4 in. wide for rails. These are simply mortised and tenoned together, and glued and wedged in the usual way, and they would be continued round the circular head as shown at Fig. 1264. A simple way of jointing up the parts round the head is to have the rails about 4 in. wide, tenoned at each end, and the curved stiles fitting on to these with open mortices, as will be understood by reference to Fig. 1264. These would be fixed round the opening flush with the edge of the splayed linings by nailing to wood bricks or other usual means.

Architraves. — These being wide and varying much in thickness, the jamb portions are prepared in two pieces, grooved and tongued together as illustrated. The architrave round the head could be prepared to fit together in two pieces, in breadth the same as those for the jambs, but of course each portion would be formed of at least two or three pieces round the semicircle, and breaking joint with the one above it. Another method would be to build up the head moulding in four thicknesses, making each thickness break joint with that below it, as illustrated at Fig. 1265, gluing together and screwing from the back. A method of connecting the circular head architrave to the vertical parts is shown at Fig. 1266. At the back a lap dovetail is made on the end of the member, fitting into a corresponding recess made in the circular one; by gluing, cramping and screwing, and leaving till dry, a good sound joint can thus be made.

Secret Fixing of Architraves. — The complete architrave must be offered up in position, the side margins accurately regulated, and, setting a pair of compasses from the arris of the head lining to the edge of the architrave less the amount of margin to be shown, scribe the bottom of the architraves to the floor. The plinth at the bottom of the outer members of the architrave not extending the whole breadth, the outer members are cut away and the plinth blocks fitted as shown at Fig. 1272, the two parts being firmly held together by gluing and screwing from the back. The system of fixing here shown is by boring a series of holes in the back of the architraves, as illustrated at Figs. 1267 to 1269. A hole is bored a little larger than the head of a screw, about ½ in. or ⅝ in. deep; then with a bit the size of the shank of the screw a second hole is bored about ¾ in. above; the wood between the two holes is mortised out, leaving a chase; then, by using a very thin chisel or other convenient tool, a V-shaped slot is formed on each side of this chase as indicated at a (Fig. 1267); then, taking a screw (the same size as the one to be used) turned into a piece of hardwood and allowed to project the exact required distance, insert the screw into the holes in turn, and, striking the end of the wood, drive the screw head along the V-shaped chase made in the backs of the architraves. Now,