I dunno . . . the boxcar is one of the Litchfield 26 foot boxcars, judging from the circular poling pocket on the lower corner iron and the flat lower edge to the end fascia:
It is obviously being used as a baggage car, and has a stirrup step at the left end of the side door opening and a wide vertical hand grab attached to the door stop at the left end of the side door.
The framing under the trainman's leg, to me, looks like a two rung partial ladder. If so, talk about your safety violation! The brakeman would have to climb up on the horizontal attachments of the grab iron to reach the ladder and climb to the roof!
And is it just me, but does the first blurry letter to the left of the door look like a capital "B", for "Baggage"??
Perhaps Ron Rudnick could clarify what we're seeing.
It is a window.Right beside it appears to be a crudely built side ladder between it and the boxcar door.Somewhat like the one in the cover photo on one of the B&Ls taken at Heywood Springs post 1885 showing one of the Cooke Consolidations.