Henry F. Seal 
Last updated: 22.06.17
All that can presently (January 2016) be gleaned about by internet searching is that Henry F. Seal is the one-off composer of S.V.A. Cadet March (1908) published by Henry F. Seal, Winchester, Virginia, USA.
Surfers are welcome to contribute information about this composer.

Further sheet music at DBE: ON HOLD