PART III

IX. [Out in the North Sea. Preparing for Action ]145
X. [The Spear of Foam ]154
XI. [The Submarine Fights for England ]164
XII. The last Chapter—in two parts—
[Doris and Marjorie have a late Visitor ]177
[Return of the Seven Heroes ]184

John Carey's Map of the Marshes


THE SECRET SERVICE SUBMARINE


PART I