Bomba, the Jungle Boy and the Abandoned City

Bomba the Jungle Boy in the Abandoned City is the fifth book in a series of American boys adventure books produced by the Stratemeyer Syndicate under the pseudonym Roy Rockwood, published in the first half of the 20th century. Various sources say the author was Howard R. Garis, or John William Duffield. Roy Rockwood is a pen name. Bomba and his native-Indian companion must descend into the bowels of a buried Inca citadel; through pitch-blackness they must negotiate steep cliffs and volcanic fumes to track down a babbling medicine-man and his army of minions. The worst hazard is navigating a huge pit swarming with snakes; by edging their way along a parapet only inches wide; at any moment a snake may dart its head out of a crevice and sink its fangs into their flesh!