Pirates of Venus — Edgar Rice Burroughs

Carson Napier set out for Mars in a secret interplanetary rocket but found him-self instead on a different world--the cloud-hidden planet Venus.

Venus was a startling world--semi-private, semi-civilized. It was a place of unmapped oceans dotted with great islands; a world whose trees pierced the clouds and whose cities squatted on their branches; a planet whose inhabitants included men, half-men, and monsters, all struggling with each other for dominance.

Carson Napier's adventures, his search for the beautiful Duare, are a Burroughs novel in the best Tarzan tradition.