Edwin Land is famous for inventing the Land Camera, also known as the Polaroid – the first instant camera. But he could invent just about anything he turned his mind to. Once his wife, in desperation, asked him to invent something to shut the dogs up! Seems they had two bull misstifs that could raise a terrible racket when they got excited.

So Edwin set his mind to it and invented a speaker that would shout at the dogs when their noise got to an intollerable decibel level. Since his was the only voice they would obey, the recorded message was in his own voice. And it worked; when the voice boomed out, it quieted them instantly.

But, one evening the Lands were having a party and the house was full of guests, really making merry and whooping it up. The noise kept getting louder and louder, until finally a slamming door did it: it reached the decibel level to activate the speaker.

BE QUIET! SIT! And of course all the guests, recognizing the masters voice did, heeding both of the commands: they all shut up and sat down.

I wonder if Edwin could invent a good excuse?