Reprint. Original publication date of Tom Swift series was ca. 1910-1919.; Alternate title on half-title page: The hidden city of the Andes.
"Professor Swyington Bumper seemed to live in a region all by himself. Though he was on board the Bellaconda, he might just as well have been in an airship, or riding along on the back of a donkey, as far as his knowledge, or recognition, of his surroundings went. He seemed to be thinking thoughts far, far away, and he was never without a book--either a bound volume or a note-book. In the former he buried his hawk-like nose"--Publisher's website.
Hidden city of the Andes
Andes Region -- Juvenile fiction.
Swift, Tom (Fictitious character) -- Juvenile fiction.