A friend found an awesome photo album at a yard sale, and allowed me to scan the photos, with permission to do as I wish with them, in trade for her having copies of the scans. The first 12 images are railroad construction photos, and appear to be of the Northern Pacific, but all the scenes but one only show narrow gauge, horse drawn Western Dump Cars working on a cut and fill. There's also a wonderful Vulcan Iron Works steam shovel.
The cars are of the HR&Co. and although it's tough to make out, on the sides, I think it reads, Halverson Richards & Co.
On the next image, note the flowing locks on the horses! Who'd a thunk it on work horses at a construction site!
Since there are no labels in the entire album, even though it's beautifully put together, I can only guess at locations and dates. From the groupings, it would appear to be in the north central part of the country, possibly Minnesota, North Dakota, or Montana. The photo prints and styles lead me to think 1870's-90's.
Steve