I became very interested in this 20 or 30 years ago...I recommend "America B.C" by Professor Barry Fell.
I was so impressed I called him up at the time and discussed some details with him
Some fascinating stuff in there; Micmac Indian language connections with Eastern Civilizations, mohomadan inscriptions confused with American Indian rock carvings,...but go ahead and read it on your own, whomever of you is interested ...I hope you saw the documentary recently on this subject (can't remember the details!) on the Learning channel or the History channel...
...I wasn't prepared for this to pop up tonight here , so nothing pre- set in my 80+ year old memory banks !?!
Bill