Jacques-Nicolas (Jaak-Nicolaas) Lemmens (3 January 1823 – 30 January 1881)
Belgian organist, teacher and composer. Received training in the supposed ways of Bach by Fetis and Hesse and in turn was sent pupils by Cavaille-Coll such as Widor and Guilmant to learn this tradition. His recitals in France left listeners stunned particularly his pedal work. His most famous work is probably his Fanfare.
Here we have the first of seven works for manuals from his 1862 École d'Orgue.
The score can be found here:
https://imslp.org/wiki/Special:ReverseLookup/130899
Clav. I: Jeux de fond 8' et 4'
Clav. II: Basson and Flute 8
Hope you enjoy.
John