Rick returned the scientist's jubilant grin, then he turned to look back at the rapidly receding pirate island, the volcano black and forbidding in the gathering dusk. "We'll be back," he promised the invisible scientists. "We'll be back!" CHAPTER XIII The Two Datus The _Swift Arrow_ moved slowly through the darkness toward the Tawi Tawi Group. Chahda was at the helm, while Rick, Scotty, and Zircon held a council of war in the cabin. The Hindu boy kept popping in and out, letting the MTB travel with locked rudder for a few minutes at a time so he could be in on the conference. "It has to be Shan," Rick said flatly. "No fishing village ever had that many vintas. And no peaceful fishermen ever fired on a stranger the way that mob fired on us. Besides, there's a mountain." "I agree." Zircon examined his pistol barrel carefully, then ran a cleaning rag through it again. "Furthermore, those vintas operated in a planned defense, in a way no fishermen would ever do. I'm convinced that it is the right island. The problem now is, what do we do?" Scotty paused in reassembling his rifle after a thorough cleaning. "Is there a choice? We can't rush the village and rescue our friends, even if we knew where they were. We'll have to get the constabulary, and the Philippines Naval Patrol, and mount an all-out assault on the place." "No!" Rick exclaimed. "We can't do that. If the pirates saw an armed fleet approaching, they'd kill Tony and Shannon, and get rid of their bodies. The fleet would find nothing at all." Chahda asked in quick alarm, "You think they kill scientists when we come today?" "I doubt it," Rick explained. "After all, one boat isn't a threat to them, even a fast one like this one. I think they'd only get rid of Tony and Shannon if they saw they were going to be invaded." "Then what can we do?" Scotty asked. "I'm not sure. Anyway, the first thing is to see if our friends are really there. When we get some more facts, maybe we can work out a plan." Zircon nodded. "That's sensible. The question is, how can we reconnoiter the island? Circling it in the boat again will only tell us what we already know." "Only one way. We go look," Chahda pointed out. Rick knew the Hindu boy was right. But getting ashore presented problems. If the MTB got within swimming distance, the pirates would see it. Of course they could row ashore by night in the rubber life raft the big boat carried. He suggested it to the others. Chahda leaped at the idea. "Silent boat is good, Rick, but not rubber boat. You remember we still got vinta?" "Of course!" Rick saw that Chahda had hit on the answer. They had left the captured vinta in a small cove on the shore of an uninhabited island a few miles to the north. "We can get it and tow it to easy sailing distance. The pirates won't think anything of a single vinta even if they see it. There must be boats coming and going all the time." "That is what I think too." Chahda ran back to the helm.