The effect upon the natives was astonishing. In an agony of fear they threw themselves face downwards in the dust, shrieking and moaning in a most dismal manner. By a pure coincidence the rock that Gerald had selected for destruction had been regarded by the savages as the home of the tutelar god of war, and its disintegration had appalled the superstitious savages far more than any personal chastisement. They realised that the power of the white man was greater than that of the deity whom they regarded as their protector in their treacherous attacks upon harmless trading and fishing vessels that stress of weather had driven into their harbours. Punctually at the time stated Captain Brookes returned with the rest of the landing-party. By means of signs the savages were told that they were spared on condition that they refrained from molesting the crews of any ships that might at some future time visit Desolation Inlet. This they seemed to understand, and by gesticulations promised to conform to their captors' commands. "Cast them adrift," ordered Captain Brookes, then turning to Gerald he continued: "Well, that's done with. There's not much doubt as to the efficacy of the ZZ-rays. But the wireless is now in working order once more, and the first message that I received is one that requires our urgent presence in the Mediterranean Sea. Until I hear further details I had better not say any more, but, rest assured, Mr. Tregarthen, that compared with our next venture, recent events are mere child's play." (_To be continued_) [Illustration: Seated up to his waist in water was the aviator, clad in an inflated rubber suit. The engine was lost to view, the tips of the twin propellers just projected above the surface.] [Illustration: fifth instalment] BY PERCY F. WESTERMAN Author of "A Lad of Grit," etc. _ILLUSTRATED BY E. S. HODGSON_ *Synopsis* GERALD TREGARTHEN, sub-lieutenant of H.M.S. _Calder_, being on leave, sails from Poole with his old school-chum Jack Stockton on board the latter's yacht _Playmate_. In mid-Channel the yacht is run down; the two friends are rescued, and find themselves on board a mysterious cruiser--the _Olive Branch_--commanded by Captain Brookes. Finding that Tregarthen is a British naval officer, Captain Brookes announces his intention of keeping him on board, and, after due deliberation, Gerald decides to fall in with the captain's plans, as far as his sense of loyalty will permit.