I'm getting some stuff ready to put on ebay, but don't know who this engine belongs to. It's obviously an old Army 2-8-0 or sure looks like one and I think it was taken either in the Memphis or Birmingham area, but am not sure. Superheated and looks like a BLW plate.
It's a 35MM B&W neg. I've strained my old eyeballs but the lettering on the tender isn't readable. Engine number is 3.

I think the third large word on the tender is Smitz. I won't swear to it, but that is what it looks like to me. I am almost positive on the S, M, and Z. Maybe those letters will give someone else a clue.

I think there was a Merrit Chapman Smith or Scott or similarly named company near Memphis that owned a Frisco 2-6-0 back in the day. I've enlarged this shot to 500% and just can't make it out.
Somebody on here will figure it out.

Could the last word possibly be "Service"?

That's what it looks like to me.

Whatever the ownership, I'm fairly certain that this is an ex-US Army "Pershing" 2-8-0, note the similarities:

http://www.railpictures.net/viewphoto.php?id=144424

That was my first impression, but since I'm often wrong I wanted a loophole. Sure has some nice fat tires on it.

I've enlarged the tender at 2400dpi and burned in the background,dodged the lettering. It looks like the one word says Service. I don't remember how the engines at Ft.Polk were lettered but in the time frame that this was shot, that would work. I think they just said USA on the tender. Too bad it's not a 4x5 or PC negative instead of 35MM.

While the environment definitely looks US, could this be a repatriated engine? There were a batch of these apparently turned over to the Italians after the WWII invasion, and the name Marsiglio Rails Service turns up on Google, but without much of a hit. Maybe a Marsiglio relative brought it back to the States? Maybe someone with knowledge of contractors in the suspected location has an idea.

It's in the USA. It was in a strip of 6 negatives (35MM) which included a couple shots of Frisco steam engines at Memphis and some GM&N and M&O photos. Look to be in the early-mid '40s as the GM&N Rebel was in one shot. I'm guessing it's in the south near Memphis due to the other shots.
I'm convinced it's a WWI Pershing 2-8-0.

Military Railway Service?

I keep wondering if that's what it says (Military Railway Service). Does anyone have an idea how the engines at Ft. Polk were lettered? I'll have to Google and see what I can find.

The engine is a Pershing all right, but I don't think that it is at Camp Claiborne, as the facilities there have no topographic relief. All the pictures of the engines there were simply lettered U.S.A. on the tender in any of the pictures that I have seen. I have pictures of Tremont and Gulf 28, which became Texas State RR #300, and as far as I know, it was the only Pershing at Camp Claiborne. This engine is quite different that the 1948 pictures of #28. The tender is different, the headlight positionning is different, and there is no power reverse, as there is on #28, but that does not rule out the possibility that those were changes made at Camp Claiborne during the war.