He determined to chance a shot at the destroyer, submerge and go out to sea again. Sighting on the dimly outlined destroyer he released a torpedo and then, without waiting to observe the result of the random shot, gave the signal to dive. Down went the _Dewey_. And in another moment, as the gallant sub slipped away into the depths, she lurched suddenly with a staggering motion and brought up sharp with an impact that shook the vessel from stem to stern. Officer Cleary was catapulted off his feet and crashed into the steel conning tower wall, with an exclamation of pain. The _Dewey_ seemed to have run hard against an undersea wall. "Reverse the engine!" shouted McClure. "We must have run upon a sandy shoal." Frantically he rang the engine room to back away. But the order came too late. With a slow ringing noise that plainly bespoke the grating of the ship's keel on the bed of the ocean the submarine slid forward and then came to a dead stop, quivering in every steel plate from the tremendous throbbing of her engines. "Great Scott, we've run aground!" exclaimed McClure as he stood wild-eyed in the conning tower. Jack was despatched to the engine room for a report from Chief Engineer Blaine. He returned in a moment to say that the ship's engines were reversed and the propeller shafts revolving to the limit of the ship's power. Nevertheless, it was only too evident that the _Dewey_ was enmeshed in a treacherous shoal from which she was unable to extricate herself. Officer Binns was ordered to throw off all possible ballast. One by one the tanks were emptied. The air pumps were working valiantly but at each discharge of water ballast the officers of the stranded vessel waited in vain for the welcome "lift" that would tell them the ship was floating free again. The last ballast tank had now been emptied and the depth dial still showed eighty-four feet. "Looks as though we were stuck, all right," was McClure's solitary comment as he gazed again at the depth dial. The engines now were shut down, the air pumps had ceased working. There was not a sound throughout the submersible, except the low drone of the electric fans that swept the air along the passageways. Every man waited in stoical silence a further word from his chief. "Jonah had nothing on us," cried Bill Witt grinning, as the group of boys retreated down the passageway leading forward from the conning tower into the main torpedo compartment. Lieutenant McClure and his officers were conferring together over the _Dewey's_ dilemma. "This ship is no fish," ventured Ted timidly, his mind engrossed in the new danger that threatened. "Well, it's a whale of a submarine, isn't it?" continued Bill in a brave effort to be funny. Ted agreed, but was in no humor for joking, and hurried amidships to join Jack, who had remained within call of his commander.