Williams O Guage Capitol Limited Series

[ajm6901]

I recently bought three cars from the Capitol Limited series on-line. I know there are four to the set. I'm trying to find numbers or designations to tell me what cars belong to the set and which one I'm missing. Does anyone have the set and the proper inventory as to how the cars are numbered or listed? I am currently looking for the fourth car.

[Joe Satnik]

Which type of passenger cars are these?

(Capitol Limited is B&O.)