Floppo and Philip are both correct, and you couldn't ask for a better ID that Floppo's. As an aside, Gloria Piccoli Wolfe of the Eagle Block family was once my bookkeeper. The following links have a picture of the front of that same train, slightly blurred as I guess the train was doing its usual 15 or so mph and I tend to use slow film and slow shutter speeds. The 493 was the lead engine and the 497 was the second. Shortly after this photo was taken, the train stopped, the 493 uncoupled and ran light ahead of the train into Durango as I have the next picture in this series of the 493 running light through Grandview.
I thought the line from Chama westward was under appreciated from a photographer's standpoint. I was fortunate enough to follow a few trains through this area and found it to be as interesting as the Chama to Cumbres section.
And a question I always had concerned the loads in these boxcars. I had heard of driller's mud, knew what it was used for, but had only a vague concept of how it was shipped. The second link is the packaged driller's mud from 2 boxcars that had just been unloaded at Aztec. The station would have been at my back. Imagine all those bages being transferred by hand from standard gauge cars in Alamosa, and then again being unloaded and stacked by hand in Aztec. At least at this point, a fork lift could then be used to load these pallets on a truck. And there were hundreds, perhaps thousands of these loads back in the 50s and 60s.
My color pictures from that excursion at Aztec appeared on a Sundance calendar some years back. I have some more b&w photos from that trip with the 483 I'll post later.
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