Quotation from: The Beasts of Tarzan

Written by: Edgar Rice Burroughs

By the time that Tarzan had travelled entirely about the coast of
the island, and made several trips inland from various points, he
was sure that he was the only human being upon it.

Nowhere had he found any sign that men had stopped even temporarily
upon this shore, though, of course, he knew that so quickly does
the rank vegetation of the tropics erase all but the most permanent
of human monuments that he might be in error in his deductions.