For the astragals, a pattern of the design is first made in wood, and from this a print is made in damp, loamy sand, in which molten lead is poured to form a casting. If many are required, the wood pattern should be sent to a foundry, and a flask made in gun-metal, from which any number can be cast. These do not require so much cleaning up to make them look smart as those cast in sand. For fixing them to the lea I soil pipes the back sides are tinned with a copper bit, and also corresponding parts on the pipes. The astragals are then folded about three parts round the pipe, and 9in. apart, and " sweated" on by means of a blowpipe. If this is neatly done, no solder will be visible. The tacks, if plain, should be cut out of 8-lb. sheet lead, about 9 in. square, the edges trued and trimmed, one end soiled 3 in. and shaved lin. wide; corresponding spaces for a pair of tacks, prepared on the soil pipe, between the astragals and soldered seams, are then wiped or floated with metal and a plumber's iron.

Cast-lead tacks have an advantage, as the nail holes are strengthened by having an extra thickness of the metal round them.