The title of this trio is a play on words as the regimental march pictures soldiers marching and perhaps firing a canon. However, the canon is a canon in the musical sense. In this piece the three parts are marching along together to the same beat, but all are playing different melodies and rhythms making this a great exercise in independent counting and playing.The 8th notes must be short and crisp, but not chopped, and the quarter notes well separated. Baritone is a good substitute for the trombone, and the second trumpet part can be well played by a French horn with a high range only up to E. A tuba part is also supplied for the possibility of using the trio as a brass choir with multiple players on a part. The optional parts make this a very useful brass trio.