How did hourglass happen? How did they even get the right amount/size of each sand particle/other physical aspects to be aligned with the time?
In: Physics
Traditional hour glasses are open at the end and capped by a wooden cap. So you can make an hour glass but leave one end open. Then you put it next to a sundial and fill it with sand exactly when the shadow on the sundial crosses a mark. Then at the next mark you stop the hourglass and poar out the excess before you cap the other end as well. That leaves you with an hourglass that have exactly enough sand to last an hour and no more.
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