The simplest method of maintaining a water supply whilst a defective street main is being relaid is to cut off the ends of the defective main at the points between which renewal is necessary, to cap the ends of the pipes that are to remain, and fix }-in. or 2-in. (according to the number of houses to be supplied) wrought-iron pipe with screwed joints, for easy removal afterwards, as shown in the accompanying illustration. This will act as a by-pass, and supply all the branches that are not disturbed. Those that come iu the defective part can be connected to the by-pass by means of tees. The temporary pipe can be laid on the surface and covered with earth out of the trench, to protect it from frost during the time the new portion is being laid. After the latter is done, the blank sockets can be burst off with hammer and hand chisel, and the connecting joints made between the old and new pipes.

Temporary Water Supply During Relaying of Main.