The Maine two footers were unique in that each line had specific freight consists that ran on a regular basis. If you find a scratchy old photo of a two foot gauge train and wonder which line it is the consist will help identify the railroad.
Examples:
The B&SR ran freights which often included the two SOCONY tank cars.
The SR&RL ran long trains of pulp wood racks for the mills. These are flat cars with high open slat sides and ends.
The KCRR freights had a couple of box cars with a cut of low sided gondola cars for coal.
The WW&F had mostly box and flat cars. In the Winslow Branch days there were flats with low side boards for coal.
The Monson had box and flat cars with the flats carrying crates or stacked slate shingles. The engines were often in the middle of the consist.
This is just a brief look at two foot freight operations, much more info is available in books and on line. The point is that each Maine Two Foot railroad had its own flavor. The WW&F Railway Museum does a great job of recreating the feel of the original line and the freight trains are a good example.