It is a 12-hour clock. The first 12 hours of the day, from midnight to midday, are called am. The next 12 hours, from midday to midnight, are called pm. However, you can tell the time without ...

Previously, [Vinnie] had been stopping the clock every evening, and hoped he would remember to start the pendulum in motion 12 hours later. This was a chore, so he decided to automate the process.

Today we can show you [Maarten Tromp]’s latest work in this field: a wall-mounted clock that he’s christened ... inner ring to indicate the twelve hours as well as the “half-hours” in ...