Title: The Hardy Boys (House on the Cliff / Secret of the Old Mill / Tower Treasure)
Description: Contains:

 - House on the Cliff
 - Secret of the Old Mill
 - [Tower Treasure](https://openlibrary.org/works/OL47950W)
Subjects: American Detective and mystery stories, Children's stories, American, Mystery and detective stories, siblings, Mystery, Juvenile Fiction, Fiction, Children's stories, Teenage boys
Places: Tower Mansion, New York City, Albany, Bayport, Bayport High, Bayport Police Station, Bayport Railroad Station, Cherryville, Crescent Theater, Ducksworth, Elm Street, Flint’s, Hardys’ house, High Street, Market Street, Morton farm, Pine Street, Renshaw, Rocco’s, Ruben Street, Schwartz’s Masquerade and Costume Shop, Shaw house, Thornton, Willow Grove, Willowville
People: Frank Hardy, Joe Hardy, Chet Morton, Hurd Applegate, Adelia Applegate, Henry Robinson, Perry Robinson, Fenton Hardy, John Jackley, Hobo Johnny, Chief Collig, Laura Hardy, Iola Morton, Mr. Morton, Mrs. Morton, Mrs. Robinson, Paula Robinson, Tessie Robinson, Callie Shaw, Oscar Smuff