In 2004, my friend the Cologne writer and photographer Jens Hagen passed away at the age of 60. Just about that time I was requested to write a piece for the Cologne Town Hall computerized carillon. Not wishing to impose modernistic sounds on the general public in the square outside the Town Hall, and on the contrary, wishing to honor the "Cologne-ness" of my deceased friend, I based "Glockenspiel for Jens" on eight well-known Cologne mardi-gras songs, which reach points of common harmony simultaneously by individually and alternately speeding up and slowing down.  Cologne's mardi-gras celebrations, the largest in Europe, reach a climax every year from the Thursday to the Tuesday before Ash Wednesday.