Great photos!
As an avid caver in the Southeast for the last 15+ years, I learned many years ago that Ruby Falls was maintained by running a pump to the top of the falls and recirculating the water since it really is only a seasonal waterfall. However, from my understanding, there is/was a very good example of a saber tooth tiger skull off the tourist trail of the cave. (
http://www.stationr.org/caving/lowercv.php)
Just down the road (~.5 miles away) is Mystery Falls, a closed cave with a pit of over 305 feet deep.
-tv