A MIDI POMMES BLEUES?
Below - Following on from the above here is the so called Blue Apples effect at Saint Sulpice ...
Update 13th August 2013: it seems some kind of verification of the window at Saint Sulpice and its replacement around 1900 [as discussed by Cherisey in CIRCUIT and reported in the above article] is found HERE. With thanks to Tingra for the heads up!