First Alarm Clock
400 BC invented
Plato needs a way to get himself, and his students, up at a certain time. And so he invented one.
Possibly the oldest clocks in history are water clocks. Water drips from one vessel into another via a small hole. As long as that hole stays the same size, and the vessels stay the same size, the clock counts down for a set amount of time. But it doesn't wake people up.
Plato had to add some bells and whistles. He ended up adding only the whistles. He added a tube to the filling vessel. It formed a siphon. When the water got high enough to fill the tube and start spilling over, all of it at once was siphoned off into yet another vessel. This last vessel was mostly enclosed, but it had thin openings, making it whistle like a tea kettle when it filled up quickly. That woke people up, and got them to their lectures on time.
credit Plato Invented the First Alarm Clock
