Vainly did the accomplished airman attempt to extricate his machine from the numbing influence. Looping, banking, attempting a spinning nose dive, he tried ineffectually to dodge the invisible but none the less paralysing beam, employing all the artifices of a flying man who had won experience in that perilous school--the Great War. It was a gallant struggle. The seaplane--a mere glider encumbered by the dead weight of a useless pair of engines--was beaten. The third and fourth shared the same fate, and whilst the four were resting on the water, the inventor demonstrated the effect of playing the ray fanwise. The moment one seaplane "started up" she was rendered powerless by the swift swing of the electric beam. Another and yet another attempted to rise, but hardly had the engines fired when they were reduced to a state of silent impotency. "That gadget will clip the wings of the Rioguayan air fleet," exclaimed Sir John Pilrig enthusiastically. "And the Rioguayans will clip ours," added another Admiralty official. "Precisely," agreed the Deputy Chief of Staff. "That wipes the air menace off the board. Now there are the submarines to be taken into account. Conditions somewhat different from those during the last war. S'pose your rays aren't applicable to underwater craft, Mr. Strong, or have you managed to solve still another problem of modern warfare?" Brian shook his head. "'Fraid not, sir," he replied. "But there's no insurmountable difficulty, I take it. A submarine's electrical engines ought to be 'shorted' by the rays. The difficulty appears to me to be the non-adaptability of water to the conditions of a concentrated current." "Meanwhile, we just carry on," rejoined Sir John. "After all, we didn't do so badly with depth-charges and hydrophones.... That will do, Captain Parr," he continued, addressing the Commanding-Officer of the cruiser. "There is no need for further trials. Will you please have a signal sent to the seaplanes to that effect? They can part company and return to Calshot." The four aircraft began "taxi-ing" into the wind, prior to "taking off". To do so, they had to pass to wind'ard of the _Cariad_, and, when at a sufficient altitude, turn and retrace their course. "Wireless telephone message, sir!" reported the Yeoman of Signals to the Captain of the _Cariad_. "Sea-plane reports submarine approaching within one thousand yards of ship. Request instructions." "Port eight," ordered the owner, with the idea of turning the cruiser so that her stern, instead of her broadside, should present itself to a possible foe. "Any of our submarines out?" he demanded of the Officer of the Watch. "None, sir," was the prompt reply. "All submarines of the Portsmouth Division were to use the Needles Channel." "Then heaven help me if she's one of ours," exclaimed the Captain grimly. "By Jove, won't it make 'em jump!"