Early South American flying information.
Another good source is Glacier Pilot, about the famed Alaskan aviator, Bob Reeve, who founded Reeve Aleutian Airways.
It mainly focuses on his Alaskan exploits, but it touches upon his time flying in South America . . . including some interesting techniques of finding a sweet spot of visibility just off-shore while trying to fly north up west of the Andes.
Great history, and a good read.