Here’s a beautiful video detailing designers Marc Newson’s process for making an hourglass. A huge cylinder of glass is placed on what appears to be a special lathe, and is then spun while heating to create an hourglass shape. Next, metal beads are added through a hole in the top until they take the appropriate amount of time to fall through the timepiece. Finally, the hole is sealed and the hourglass is ready for use. [via kottke]

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