1047. John's tankless toilet often failed to "gulp," his word for the sound it made after it "swallowed." If it doesn't gulp, I have to reflush; if reflushing fails, I have to plunge, John always said. Recently, both actions had tediously become part of the routine whenever John used his throne. Finally, he told the super, who tested the toilet. He said, "The flush is weak. I'll order a new bowl, because it's also leaking. Your downstairs neighbor has a small—for now—'bubble' on his ceiling. He says you flush '10,000 times' a day. If you ever notice that the water level is low, call me ASAP and do not flush again, although it might be too late." Next day, John flushed but heard no gulp. He flushed again, and again—and again. The water level suddenly lowered. Uh‐oh, John thought. Moments later, someone was banging on his door. 4.7