The "piers" in the photo are the foundations for the rotary coal car unloader that the L&N installed in 1927. This equipment rotated railroad coal cars so their contents could flow down into a hopper then be sent onto ships through chutes. At the time it was the most modern coal unloader in the world. The unloader was about the only part of the wharf left after the fire in 1955.
http://home.mchsi.com/~jerrym151/Continued/SouthernStates3.h...
may have one or more photos of this structure.
Thank you for this information!! Has been in debate in our family conversations for many months. Now I am validated in the facts shown!!