It all began because Tess Kenway became suddenly and deeply interested in aeroplanes, airships and "all sort of flying things," as Dot, the smallest Corner House girl, declared. Perhaps one should modify that "suddenly"; for Tess had begun to think about flying-as a profession-as long ago as the winter before (and that was really a long time for a little girl of her age) when she had acted as Swiftwing the Hummingbird in the children's play of The Carnation Countess.