The mystery of the non-flushing electronic toilet

Drawing to an Inside Flush: a tale of two toilets – by Steve Mirsky

In early August a short item crossed my desk about troubles on a movie set in Mumbai, formerly known as Bombay. Actors and crew were trying to film a scene in a public restroom for the Bollywood blockbuster Keep at It, Munnabhai. But when the actors walked past the autoflush urinals, they inadvertently set off the sensors. The water would noisily flow, and the scene would go down the drain. "At one point, with so many unit members inside the loo, all the flush sensors went berserk and started flushing simultaneously," recounted Raju Hirani, the film's director, according to the Associated Press. "We actually had to vacate the loo briefly to stop the urinals from flushing."

The flushing toilets of Mumbai (officially ranked as the 14,287th Wonder of the World, by the way, just behind the Hanging Gardens of Piscataway but before the Colossus of Killiecrankie by the A9 road) took me back to my own misadventure with automatically flushing toilets. This escapade took place at personal computing's headwaters, the headquarters of Microsoft.

The year was 1997: Researchers publicly announced the existence of Dolly the cloned sheep, The Simpsons passed The Flintstones as the longest-running animated television series ever, and newfangled autoflush toilets were helping America stay hygienic. It was a heady time.

I was at the annual meeting of the American Association for the Advancement of Science, held that February in Seattle. Journalists attending the conference were also invited to visit Microsoft near Redmond. So I went and inevitably had to go. I left a lecture (which I recall was about the ongoing efforts to create reliable voice-recognition software, just to give you an idea of the scope of that still unsolved problem) and wandered until I found a bathroom. I entered, put the seat up and proceeded as usual. After which, being committed to the commonweal of my fellow fellows, I tried to flush. And was thwarted at every turn.

While searching in vain for a handle or button or even dangling chain, I noticed a small, dark rectangle in the middle of which was a luminous red dot. I knew then that I was in the presence of electronic technology.

Clearly, this object was a sensor designed to automatically flush the toilet once the end user zipped away. And yet no flush would gush, no surge would purge, no swirl unfurled. I refused to leave the room before disposing of all the evidence, so I began a meticulous debugging analysis. And through a careful consideration of the geometries, relative positions and functions of all the objects in the setup, I concluded that the sensor had been located in a place where it could be blocked by only one thing--the upraised seat. With the seat up, the system was convinced that a request was still being processed. So I put the seat down.

That simple act, the savior of millions of marriages, solved the problem. What we used to call "the electric eye" suddenly was alerted to the fact that the task was complete. Water began its flow to the sea, and another wee aliquot of processed caffeine started its journey to Puget Sound.

As I washed up, I reflected that the situation at Microsoft was probably explicable in one of two ways. One possibility was that whoever installed the componentry had used state-of-the-art motion-sensor technology along with deep ergonomic theory and application to trick men into putting down the toilet seat. The other option was that they had accidentally cobbled together a Rube Goldbergian arrangement that in effect replaced the old-fashioned toilet-seat handle with the seat itself. As a Windows user who has to click "Start" to turn my computer off, and as a man who knows that most men wouldn't try all that hard to flush in the first place, I'm betting on the latter.