PLUMBING.
As soon as the plasterers have removed their stagings from the house, the plumber can at once complete his piping work. In some cases it will have been necessary to run the main soil pipes concealed behind the plaster, but it is much better if they can be run in plain sight. Extra heavy pipe is called for, to be plain and painted on the outside with red lead. These pipes should have been tested for sand holes before delivery and being plain any imperfections in the casting may be readily seen, as would not be the case if they were asphalted as usually seen. The joints of the soil-pipe will need especial watch ing to see that they are not slighted in any way. All the joints must be made of oakum, driven in tight, and finished with melted lead which will be poured around each joint and then caulked all around after the pipes are in position. (Fig. 43.) It is never well to com plete the joints before securing the pipes in place as the jar of this handling may loosen the lead. The pouring in of melted lead will not secure a tight joint as the lead shrinks away upon cooling and it is necessary to force it again into contact with the pipe. This is the object of caulking, and if well done the lead in the joint will show marks of the iron all around.
Lead Pipes. Lead pipes will be most easily examined on delivery, when the ends of the coil will be stamped with some figures or letters to denote the weight per foot. After the pipe has been cut it will be next to impossible to tell if it is the right weight by appearance. All lead pipe which is not new should be rejected, as well as any show ing unequal thickness. The running of lead pipes should be carefully watched and boards should always be put up, against or upon which the pipes may be securely fastened. Lead pipes which are run vertically should be fastened by hard metal "tacks", which are soldered to the pipe at intervals of about three feet. Unless this rigid fastening is clone, the pipes will "crawl" and droop downward by alternate contraction and expansion. Horizontal pipes may be secured by bands but should
have a continuous strip of wood to support the entire length, or they will in time sag down and form a hollow place, from which the water cannot be drawn when pipes must be emptied. The pipe should be made to rest upon the straight support and never be allowed to take an upward bend in its level course, as a bend of this kind will soon become filled with air and will eventually stop the flow of the water unless punctured at the highest point.
All the joints in lead pipes should be wiped joints as specified and no cup joints, which are more easily made, but not so strong, should be accepted. The joining of lead and iron pipes must be made by wiping to the end of the lead pipe a strong brass "ferrule" which can be caulked into the iron pipe. This will need to be looked out for as it is a great temptation to many plumbers to putty the lead pipe into the socket of the iron pipe.
Brass Pipes. For the hot water system brass pipes are to be used as they are not affected by the alternate warmth and chill of the water, which would cause lead pipes to sag between the supports. Indeed, if the additional expense is not too great, it will be worth while to make all the supply pipes of brass, which can be obtained either plain or coated inside with tin. If brass piping is used it must be put up so that the angles and bends are free to move a little, or the expansion and contraction will strain the fittings and produce leaks. The effect which the water will have upon the pipes is a matter which should be considered, but can only be determined by local examination, and recommendations as to the use of piping must be made with reference to the analysis of the local water supply. If brass piping is used it should be semi-annealed and specified as "iron size", that is, the thickness must correspond to that of iron pipe of similar size, as distinguished from so-called "plumbers tubing", the use of which is not to be recommended.