The Airplane Boys among the Clouds

"I tell you, Elephant, it's the Bird boys, and nobody else!" "But they had a monoplane last summer, Larry; and you can see for yourself it's a biplane out yonder over the lake. So that's why I thought it must be Percy Carberry and his crony, Sandy Hollingshead." "Shucks! stir up your think-box, Elephant. Get a move on your mind, and look back. Don't you remember Percy lost his old biplane when he took that trip down to South America, and had some trouble with the revolutionists in Colombia?"