This information was taken from the Chattanooga Choo Choo website:
The Terminal Station was erected in 1908, with its centerpiece - a magnificent dome - that rose majestically over the concourse. Built of steel and concrete and buttressed by huge brick arches, the dome rested on four steel supports 75 feet apart. Suspended from the ceiling were four brass chandeliers, each with 40 lights circling an 18-inch opal globe. From an architectural standpoint, this dome over the entire 68 x 82 foot general waiting rooms was the most attractive design feature of its time.
It was on the underside of this dome, the part in view above the waiting room, that the only attempt to decorate in colors was made -- artistic plaster embellishments of heraldic emblems, which are now fully restored. The dome was truly lavish and beautiful in its different prismatic colors, especially when lighted at night.
This photo was taken near dusk on a clear night.
Train service stopped in 1970, and the depot was converted to a Hotel. The main room with the dome is now the hotel lobby