Storm pedal!!! Yes, this piece by Michel Corrette features the storm pedal. Cavaillé-Coll organs had a L'Orage pedal on the far bottom left hand side which activated six or seven notes from the bottom of the pedal board upwards. The sound effect is meant to resemble a "storm" (cluster of notes). To perform this work on an organ without a storm pedal, you would need to move your feet sideways and activate as many notes as possible in the bottom octave.
This work is in the public domain and maybe be downloaded from IMSLP: http://imslp.simssa.ca/files/imglnks/usimg/3/30/IMSLP128472-WIMA.30c3-Corrette_Suite_2eTon_10.pdf