Berlin
A guide to actually using the Set Theory Clock
Stumped by the Mengenlehreuhr? Here's how to tell the time using Berlin's oddest clock.
The time is displayed in 24-hour format, and is determined by sequentially multiplying and adding the rows of coloured lights, which represent the following units of time:
Hours (first two rows)
Each of the red lights in the first row represents five hours.
Each red light in the second row represents one hour.
Minutes (final two rows)
Each red or yellow light in the third row represents five minutes.
(Note that, for easier recognition, quarter hour divisions are marked using red lights).
Each yellow light in the final row represents one minute.
Seconds
The round light at the top of the clock blinks every second.
Illustrated examples
Row 1: 2 x 5 hours = 10 hours
Row 2: 2 x 1 hours = 2 hours
Row 3: 11 x 5 minutes = 55 minutes
Row 4: 1 x 1 minute = 1 minute
Total: 12 hours and 56 minutes (12:56)
Row 1: 2 x 5 hours = 10 hours
Row 2: 1 x 1 hours = 1 hours
Row 3: 2 x 5 minutes = 10 minutes
Row 4: 2 x 1 minute = 2 minutes
Total: 11 hours and 12 minutes (11:12)
Row 1: 3 x 5 hours = 15 hours
Row 2: 1 x 1 hours = 1 hour
Row 3: 9 x 5 minutes = 45 minutes
Row 4: 3 x 1 minute = 3 minutes
Total: 16 hours and 48 minutes (16:48)
Acknowledgements to Berlin Clock, where you'll find a working online version.
