In the 1930s classic movie “The Wizard of Oz,” The Wicked Witch of the West uses a sand-filled hourglass to gleefully remind our hero Dorothy that she only has so much time to live while the sand is ...

So you need your project to pause for a preset number of minutes but you can’t do it programatically? Why not connect a micro-controller to an hourglass egg timer to sense when the sand stops moving ...

An hourglass tells you what it is in the name — a glass that you use to measure an hour of time passing by. [EDISON SCIENCE CORNER] has built a digital project that mimics such a thing, with little ...