《The Outdoor Girls on Pine Island》 - 免费有声读物

In this 7th volume of the "Outdoor Girls" series, the girls spend the summer in a bungalow on Pine Island. The young people accidentally discovered a gypsy cave concealed by underbrush, and succeed not only in rounding up the band of gypsies, but in recovering several valuable articles that had been stolen from the girls. (Summary adapted from the book)