Arches of moderate span, say about 6 ft., can be worked as follows: - Two pieces of timbering should be bolted to the caps of the brickwork columns, on which another piece is fixed to take the bolt which is in the centre of the arch, and holds the radius rod in position (see elevation of arch, Fig. 1). A radius rod should be prepared, to the end of which the templates necessary to run the mouldings can be fixed. The plain part of the wall above arches should be flanked in with Portland cement, this then forming a screed on which the mould to work mouldings can travel. A mould should then be cut from a piece of wood to the shape of the moulding, 1/4 in. less being allowed in every part to allow for the finishing coat. After this has been used to run the moulding in cement, another should then be prepared to the exact shape and size required, this one being faced, as shown in section of arch (Fig. 2), with either copper or zinc. The fine stuff is then laid on the cement backing, and worked to the required section by moving this mould round the arches by aid of the radius rod, as shown. After the moulding has been finished, the key block can be moulded and placed in position. The intersections of the arch mouldings can all be run by having the top part of the template, from the dotted line A upwards, hinged on to the radius rod, so that it can be held back while passing over intersecting points.

Fig. 2. Method of Working Mouldings on Arches.