Henry is currently playing with irish side Portadown and is apparently a left footed centre half. Not much else is known about him - although he's less than six foot, which is a bit short for a defender.
One of the other trialists expected to join the squad at some point during the summer is Hibs striker Sam Morrow. Chances are there will be more, which is surprising considering MacPherson hasn't signed a single player he's had on trial since taking over at the tail end of 2003 - although Richard Brittain and Alex Burke both signed last summer after a spell training with the squad.
meanwhile, it seems that Saints multi-signing exciterment isn't over. There are reports that there will be at least two more arrivals - possibly Stephen Glass and Rab Douglas - before the squad jets off to Italy next weekend.
Story sources: Sunday Mail, Sunday Herald