Hi,
I was wondering if this might be a 4 track PRR mainline. The PRR did use gauntlet track in several places.
All I know about it is in the caption in the scan and it is Pennsylvania.
I'd not considered 4-rail dual gauge. This is a real possibility. Since there is no date other than the book was placed in the 1800's, your guess is as good as mine.
I wonder if there was a bridge or tunnel behind the camera?
It almost looks like the near "points" stub can select either track of the gauntlet (assuming it is a gauntlet) and the far stub selects the siding MAYBE?????
Doug vV
PS PRR's stated gauge (in official reports) was 4' 9" - wide gauge