Have any photos of these you can post on here? I think I asked before about one shown in the station at the Shelburne,
Vt. museum RR station, of which I could not get a good photo, high up in a dark building. It shows a "combination" of a horizontal steam locomotive attached from cab back to a passenger car, all as one unit. There were also inspection engines
with, sometimes stepped, seats in a coach compartment around the front of the boiler and smokebox (so company management could get a good look at a lumber dray stalled on the tracks before they hit it 
). In addition there were
steam coaches, similar to gas electrics, offered by Baldwin, Alco, Unit Stanley, and others, but these last are well covered
in the Keilty "Doodlebug" books. I am not aware of anything addressing those earlier critters.
