1863. Bailey, Gilbert Stephen. 1863. The great caverns of Kentucky: Diamond cave, Mammoth cave, Hundred dome cave. Published – Chicago: Church and Goodman, illus: b&w: maps; 63 pages. https://archive.org/details/greatcavernsofke00bail
I came across a book for sale on eBay tonight that had been published in 1863. The price is quite a bit out of my league, but a pdf of the document can be downloaded from http://www.archive.org at the link above.
Why I am posting this is because even though it is in archive.org my previous searches had not found it. I wonder why not? I guess I just accidentally skipped over it.
It is still just cool to find a new book on the cave after all this time.
Edward Forrest Frank