Me, too. In fact, I woke this morning with that question in my mind, a question I have never considered before, even fleetingly: If I had a house at the bottom of the ocean, how would I get rid of the gray water? Which led to the question: How do submarines do it?

Turns out, submarines - at least some submarines - have two kinds of heads: gravity flush heads (that drains into holding tanks (which also collect “discharge” from the galley sink, the scullery sink, the scuttlebutt or drinking fountain, the shower, et al) and expulsion flush heads that look like this and discharge directly into the sea.

How?

With lots of levers, pedals, sea pressure gagues, and things like “flood, blow, and discharge lines.” First, flood the bowl with seawater from a “sea valve.” Then pour your, er, coffee into the bowl. Next, “flush” by emptying the bowl into an expulsion chamber that will eventually push your coffee into the sea. Push a “rocker valve” one way to admit “air from a low-pressure line into a small volume tank until a pressure of approximately 10 pounds above sea pressure is reached. When rocked in the opposite direction, the valve directs the volume of air into the expulsion chamber. A sea pressure gage, a volume tank pressure gage, and an instruction plate are conveniently located.”

And that, my friends, is how to shed water from a sealed, submarine edifice. It sounds dangerous. Maybe I’d prefer a tree house after all.