Bruce,
The round house pattern in the second picture is the “Q’s”.
The first picture’s round house was the Illinois Central’s. It sits immediately south of Centralia in the community of Wamac. Wamac was created by the IC when the Fathers of Centralia decided to try and blackmail the IC when they needed to expand around the 1870’s. They felt that the original IC created community was now important enough that the IC would pay a bigger price for land for expansion within the city. WRONG, the IC went immediately outside the southern boundary of Centralia and incorporated Wamac, named for WAshington, MArion and Clinton counties, since the property in question straddled all three counties. Throughout the history of Centralia, the town’s fathers have lost pissing contests to the railroads, but they never seem to learn.
Right now the battle is over a proposed railroad crossing/overpass on the Southern, now Norfolk Southern, south of town. Always interesting politics to watch.
As the worm turns.