Q. Please explain to me the cause of water smelling bad for two or three months at a time, which is pumped from a cistern through gal-vanized-iron gas-pipe previous to showing the bad odor? The water seemed perfectly pure, and it then became good again - that is, no smell was noticed. It bothers some of the oldest pump men that have worked for me. Please explain also how I can stop the noise caused when the waste-water is running from my bath-tub. I send a sketch, showing their location and down-stairs connections with my pipe. My stand is in the corner, and tub-waste connects with it on a line of the floor; down stairs a stand-waste connects with same, which empties in front gutter.

A. If water smells badly it is contaminated. An analysis might reveal in what manner. The sketch sent by our correspondent is rather indefinite. The size of the waste-pipes is not given. The noise referred to in all probability is caused by the waste-pipe being of smaller diameter than the outlet of the bath, or there may be traps in the waste-pipe which retard the flow and produce a gurgling noise. If the waste-pipe is of sufficient size so that it cannot be charged, and there are no traps or depressions in it, there will be no noise to cause annoyance.