“No way of simulating it, anyway,” the Captain commented. “But it’s about the only thing we leave out in this training.” “There’s one big difference,” March said. “In training, if you make a mistake, why you just get a bad mark from the teacher. In real submarining in war time, you’re likely to get—dead. And carry a lot of others along with you.” “What do you mean?” the Skipper asked. “That’s true at the beginning, of course, but not now. You’re really navigating this boat, Mr. Anson. Nobody else is doing it, and nobody’s checking up on you. If you do it wrong, we’ll pile up on Montauk Point!” March gulped. And Stan looked a little worried. “What’s the matter, Stan?” March asked. “Are you scared? Think I’m not a good enough navigator?” “No, I was just wondering,” Stan said, “if the same thing applied to me—if I’m really totally responsible for all these engines on this trip.” “Of course you are, Mr. Bigelow,” the Skipper smiled. “And I’m sure you’ll handle them very nicely, just as I’m confident Mr. Anson will take us just where we’re supposed to go. You are not allowed to take over these duties until you have proved conclusively, in your previous work, that you could do so.” As darkness descended over the waters of Long Island Sound, the training sub surfaced and found herself just where she was supposed to be at that time, much to March’s relief. Hiding behind a point of land near the end of Long Island, they charged their batteries, while a skeleton crew stayed on watch. Most of the others went to bed for a few hours’ sleep in the bunks which lined the walls of most of the rooms. March and Stan shared a tiny cabin, but were not in it at the same time, as their watches followed one another. Before dawn the next morning the sub set off from its cove, submerged, and followed the next course under water. Sending up the periscope at about ten o’clock, the Skipper saw the target boats at the designated spot and the sub went through a series of simulated attacks on enemy shipping, crash diving to get away from “destroyers” attacking them, lying on the bottom with all motors shut off for a spell, then sneaking away at a depth of two hundred feet in a circuitous course to outwit the enemy waiting for them. During all the trip the Skipper and Lieutenant Commander Sutherland were closely observing, without seeming to do so, the actions of March and Stan, and of the student diving section which had shipped with them for this special trip. They were interested in seeing not just whether the men could handle their jobs, but _how_ they did it—if calmly or with too much tension. On occasion one or the other of the two senior officers would give a conflicting order or misunderstand something reported by Stan or March, just to see what happened. Not once did Stan or March become upset, and the two older men smiled at each other meaningly. [Illustration: _The Sub Set Off and Submerged_]