Going from memory of some historical research that I did some years back, I would guess the time era of the photo as being in the 1910-1917 era. Though it is hard to see at the resolution of this photo, the locomotive in the photo appears to have a diamond stack and an electric arc headlight. I believe that the arc headlights began replacing oil headlamps by around 1910 and diamond stacks were pretty much gone by the late teens, thus the locomotive having both suggests a period likely in the early to mid-teens. By the early '20's, the arc headlights were being rapidly replaced by incandescent headlights, as well.
It is indeed a fascinating photo--a lot has changed in the Chama yard in a century or so, but a whole lot hasn't.
I do wonder what the round object is on the platform--a roll of newsprint paper, maybe?
The Rotary in the photo could be either OM or ON--both were used on Cumbres in that time period (the OY didn't come along until 1923). ON would later go to Salida/Gunnison.
Edited 1 time(s). Last edit at 06/29/2015 09:40PM by Wade Hall.