Alphonse Mailly taught at the Brussels Conservatory for 30 years.
The following appears in my Pratt New Encyclopedia of Music and Musicians - published 1924:
Alphonse Jean Ernest Mailly b. Brussels 1833 d. Brussels 1918
Brilliant Belgium organist, pupil of Brusse.s Conservatory and from 1861 teacher of piano and organ there, with many tours as a virtuoso. Wrote an OrganSonata, many Fantasias (including one with orchestra), a Serenade for flute, violin, cello, organ and piano, a Piano Trio, piano pieces, motets, etc. (sent by Patsy Harris <firstname.lastname@example.org>)