I stumbled across a double feature on YouTube tonight while researching New York freight yards. Made by the New York Central in the 50s, there are some great shots of how a yard works from the hump yards to the inspection pits. Includes a nice overview of different types of freight cars, a few minutes on changing wheels, and some shots of interesting tools in steam locomotive servicing. The "Leave it to Beaver" type music gets tedious after a few minutes, but it is worth it. The second shorter film at the end is a general "railroads are heart of America" piece and just a few minutes long.