Here's an odd piece of railroad history.  What is it?

 

This answer is from Matt 'CrazyDelmar' Davis:

A locomotive from the Chicago Tunnels Railway. The line ran underground beneath buildings in the loop area delivering mail, paper, and other supplies, and removing waste and other items. The only surviving pieces of rolling stock are located at the Illinois Central Railway museum near Union, IL.

Thanks Matt

 

The above photo is from Bruce Moffat.  Bruce is the author of the book:
"The Chicago Tunnel Story: Exploring the railroad "forty feet below""

Bruce plans to write an article for this web site on the, now defunked, subterranean railroad.  The story of the vast Tunnel System gets more interesting after the railroad is abandoned.