It’s been a centerpiece in Union Square now for 15 years, but it still bewilders many a passerby. No, these numbers don’t count the national debt or the acres of rain forest being destroyed, as some have suggested.

It’s part of Public Art Fund installation by Kristin Jones and Andrew Ginzel for The Related Companies. The numbers count the 24 hours of the day, while showing what is remaining in the day. For example, in this photograph, the time is 8:21 (or 20:21 in military time), with an additional 26.5 seconds. Reading from the right side, there are 3 hours, 38 minutes, and 33.4 seconds left in the day. The center digit counts hundredths of a second. According to the Public Art Fund website, the digital clock is “meant to convey the energy, exhilaration and ultimate flux that is the essence of New York City.”

Between 2010 and 2011 the digital clock went off kilter, inadvertently throwing off New Years Eve revelers by 40 minutes. It’s since been fixed.

Connected to the clock is the art installation, Metronome, which is a rather mystical piece intended to “create a composite work embracing the past, present and future of the city. Metronome encourages a dialogue between the public and their city as the eight elements evoke the city’s pulsing rhythms, daily rituals, and its astronomical and geological history.” It contains a massive cast hand of George Washington from his statue in Union Square, steam is released out of the center, and the metal wand is synchronized with the phases of the moon.

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