@roger,
I have an entire set of photos 10x12" of the entire rolling stock of the Reading Railroad. It is a collection of inventory that was made for the war department in 1940 . It has everything of all their engines (COWS)
, yard engines, mine crawlers, tenders, Spinos, and trollies . I also have a similar collection of "crumb boxes" (Cabooses). Back then the metal skinned ones were a new thing and the Reading still had plenty of wood siding caboose.
Its a pile over 300-400 photos long. Ive been offered a hefty amount for em but I think Im going to will em to a museum that knows how to care for em.
The photographer's signature and a war department number is on the back of each one, as well as the makwr and tech specs an wheel configurations.
I guess the WD was getting ready for the eventuality