Only be a good workman who knows where to use lead pipe and Where to use brass and iron, how to properly place the drains and the piping, and how to properly mount the fixtures; but he must be versed in the principle of sanitation, the proper location of tanks, the sizes of water and drainage pipe, the laws of water ?ow, pres sure, and many other questions involved in giving to any dwelling, office building, or factory, adequate and well designed water and.