Been practicing carols past couple of days. Decided to give this a go on Caen starting with the Recit and Positif strings and undulating stops. Recit has suboctave and is played an octave higher. Then the Gambe of the Great is added with sub-octave. Added the 8 + 4 foot flutes of the Recit and Positif, then the Basson-Hautbois and Clarinette of the Positif and it builds from there adding to a final small tutti - all the big reeds off, but mixtures and smaller reeds on.
The words are by C.F. Alexander and a year later English organist Henry John Gauntlett set the poem to music. This version is harmonised by Dr Arthur Henry Mann, who was organist at Kings College Cambridge.