We've seen it before, here it is again!
Cheers!
Sure , @deandddd - Athanasius Kircher was no less an intellectual than Newton or Galileo...just that he didn't get quite as much "patronage" as the other two and hence is less known !
Regards
@deandddd, that's a really great list. Thanks for sharing it. While these may have been discussed before, I found some remarkable gems in that list that I had not actually heard of before!
Just take a look at the 1886 book by Frederick Culmer Sr.: "The Inner World. A new theory setting forth that the Earth is a hollow sphere containing an internal habitable and inhabited region."
Readable copies:
And I'll make one comment tot all of you ...
The way things are going, we mightnot be able to communicate on the interneat as we have in the past. So it is important to gather a collection of hard copy books in order to perserve the information that we have about underground worlds.
Dean