Moscow Kremlin clock strikes the small musical phrase each 15 minutes. In the first quarter of hour the phrase executes once, in the second — two times, in the third — three times, and in each full hour the clock strikes the musical phrase four times and then the clock strikes the bell once at one a.m., twice at two a.m., continuing in this way up to twelve times at 12 noon, then starts again, striking once at one p.m., twice at two p.m., up to twelve times at 12 midnight. See more information about Kremlin Clock: http://en.wikipedia.org/wiki/Kremlin_Clock