Walking along Paddington Street in Marylebone, you might easily miss this glass sculpture, appended to the front of a modern building:
What at first glance might seem to be a random assortment of glass panels is actually a musical code, waiting to be cracked.
Those who read music might be able to decipher without further help, but for everyone else, a code is provided on a plaque below the piece:
Hum or sing the 42 notes in the order specified on the left (or on the main artwork) and you should find yourself reciting a well known ditty. That's the theory. We've tried and tried, and we can't make it fit a tune we know. Any luck?
The musical intervention is the work of Julia Vogl, and you can find out more about the installation here.
The puzzle reminds us of another sculptural riddle, over in Pimlico, where the statue of Ada Lovelace fronts a coded message on punch cards:
With thanks to London Remembers for the tip-off.