A "T" in Whyte notation designates a tank locomotive, equipped with side or saddle tanks. There was also a type called "well-tank" locomotives (designated "WT") That may be what this is, but I'd be more inclined to call it a Forney-type loco.
A bit of trivia here..........does anyone know the "code" for the 2-6-4
wheel arrangement (berkshire, mikado, consolidation etc.)?....no fair googling!!
It was one of the rarest wheel arrangements in N. America but was used extensively in Europe. I would not have known what it was called except that I ran across it just last week while reading up on Forney locomotives.
J