The Hourglass is one of the oldest ways people us to tell time they were used in the Ottomans, Romans. Greeks and etc. They have many ways you can make an hour glass with sand, metal, glass and wood because it is super simple and if you are bored you can just do it.
It relates to engineering because you can design it any way you want because their is no one way to do it. If you like old things with a modern twist this is for you.
