"Mr. 'Blimp' might try a bomb himself," suggested Ensign Andrews. "I believe he carries a few." "Not as powerful ones as we carry," Darrin answered. "Besides, he has to be at a greater altitude, when hunting submarines, than it's handy to drop a bomb from. There is too much margin of chance that the enemy craft will graze by when the bomb is dropped from the air. In our case, if we drop when directly over the Hun, there can hardly be a miss, and it's the dirigible's business to tell us when we are directly over the enemy." In the meantime, on board the destroyer, all was made ready, and Dave followed the same tactics as before. This time, too, there was a normal explosion, though a solid hit was made and the submarine destroyed. Apart from the "blimp's" report there could be no doubt as to the destruction. The spread of oil on the surface of the sea told the story. "If you and we hurry, we may bag another before dark," Dave sent by wireless, as the aircraft started back again. "We'll do our best, believe us!" came back the word. In the late afternoon a slight haze came up, which gradually deepened. Darrin followed for a few miles, keeping the "blimp" in sight. She was some six miles away when a radio message came from her in code in these words: "Can you see steamship about four knots north-west of us?" Dave challenged the lookout on the military mast, but that seaman reported the weather a bit too thick to enable him to make out the steamship. Darrin accordingly wirelessed back this information. "Looks like a tramp steamer," came the next message, "but she acted suspiciously when she sighted us. Her skipper appears perturbed, which he would hardly be if his business is honest. Weather is thickening so we may lose him in the haze. Better close in." "Will do so," Dave replied. Then followed explicit directions as to the course the destroyer must follow. The next code message from the airship was: "Skipper of steamship so bothered that he appears to be rigging anti-aircraft gun. Am about to signal him to stop for search." Despite the haze over the sea the "blimp's" movements could still be made out from the deck of the destroyer. Mast lookouts and those on bridge and deck followed the "blimp's" movements with keen interest. "He maneuvers as if he were closing in on the steamship," declared Ensign Andrews. "If the steamer's skipper uses anti-aircraft guns the dirigible's commander will be justified in dropping bombs," Dave returned. "It's a stupid piece of business for any lightly armed steamer to attempt to resist a 'blimp.' But of course the steamer's skipper does not know that there is a warship so close." "The rascal's firing on us," reported the "blimp." "If you'll keep back we'll close in and talk to the stranger," Darrin suggested, by wireless. "We're hit," almost instantly came the report from the airship. "Badly?" Dave asked by radio. "Investigating. Report soon."