The Answer is.....

Cincinnati people will know this. The Mt. Adams Incline, here's another view with the Rookwood Pottery on the top left. Say thanks to Shorpy's website for helping us understand. The venicular arrangement was to make it possible to run the street cars up the high hills surrounding the main city business area. The massive structure between the two buildings is an archeological remnant of the device. The buildings are likely just visible in the older photos. Other hills surrounding the city had Inclines, as well.