Geoff backed his chum up with a vengeance, gripping the man's hands and tearing his rifle from him. Then, seizing him by the legs, while Philip managed to grip the man's shoulder, still holding his mouth firmly closed, the two rushed him to the side and flung him over into the river, Geoff tossing his rifle into the water after him. "Now back," he whispered to Philip, taking him by the sleeve of his coat, "the chap is sure to shout and alarm the others. Let's get back and down to our dinghy till things quiet down again. Of course, if he doesn't shout, all the better, for then we shall be able to tackle the other business." Even before they could turn to run along the deck, the splash which the man's body had made as it fell into the water was followed by a shriek, and then by a hoarse shout as he sang out loudly for help, by a shout which stirred the silence hanging over the river, and brought the men bobbing up from their quarters for'ard, and those three officers stumbling up the steps of their cabin and out on to the deck. And in that short space of time Philip and Geoff had stolen aft, and, slipping over the rail, had slid down into the dinghy. "Quite a little commotion!" laughed Geoff as he listened to the shouts above him. "Of course I'm sorry for the sentry." "Rather a dirty game, eh?" said Philip. "But I suppose all's fair in war, eh, Geoff? And besides, supposing I had been the sentry, and you'd come along and chucked me overboard, I should naturally enough howl out so as to give the alarm and to ask for assistance; but I shouldn't be dead, not by a long chalk, and, seeing that I can swim, I should do my best to keep myself afloat till the river twisted and deposited me on one of the banks. If that sentry's sensible, that's what he'll do; on the other hand, if he can't swim--which is hard lines, of course, but not our fault, and a matter we can't deal with--of course, there it is, he'll drown, and neither of us can help it. The best we can do is to wish him luck, for he's now out of the way and not likely to harm us." Meanwhile there was pandemonium on the deck of the vessel, shouts and cries coming to the two young officers in the dinghy, shouts and cries which were drowned by the stentorian voice of one of the officers, undoubtedly the bald-headed individual who was senior of the party. "What's that? What's happened?" he bellowed. "Someone shouted, and I'm sure I heard a splash in the river. Where's the sentry? Pass him aft here so that he can report on the incident." But of the sentry there was not a sign, though a faint shout coming from farther down the river, whither the unfortunate fellow had now floated, was sufficient evidence of the cause of that splash which the Commander had heard, and explanation of the absence of the sentry. "Deserter!" cried one of the officers, seizing upon the first idea which came to him.