The news had barely reached the Admiralty, when telegrams were pouring in from Manchester and Liverpool, reporting that both places had been shelled from an unknown type of craft that had appeared sixteen miles west by north of the Bar Lightship. In this case, the firing lasted only a couple of minutes or so, for on the appearance of an Isle of Man packet-boat the submarine hastily dived. That pointed to the fact that the crew of the submarine were evidently "jumpy", otherwise they would not have dived simply because of a small and unarmed steamer. . . . . . . . . . True to his promise, Brian Strong had a complete apparatus ready in the specified time. In the presence of a number of naval experts, the device was submitted for trials. For the sake of secrecy, the apparatus was placed on the light cruiser _Cariad_, the vessel with the experts on board being ordered to proceed to a position twenty miles south-east of the Nab tower. Four modern-type seaplanes from Calshot were detailed to play the part of hostile aircraft. At the time specified, two of them were observed approaching from the nor'-east at an altitude of 2000 feet. The inventor, feeling far from cool and collected, peered through the telescopic sights. In spite of the fact that the rays had been proved, he was assailed by doubts. Supposing something--a minute adjustment--was in error and the device failed? Or if the current should prove too strong or too weak for the sensitive instrument? He feared failure, not because the apparatus might be defective, but by reason of the ridicule that would be hurled at him. Slowly, Uncle Brian trained the projector, still hesitating. The nearest seaplane was now a bare two miles away, flying serenely, almost defiantly, in the cloudless sky. "Three thousand yards," chaunted the range-finding officer. Some of the experts shrugged their shoulders. The rays were to be released at nine thousand yards. For all they knew, the inventor had done so, but without effect. At last, with a nervous jerk, Brian Strong depressed the lever actuating the mysterious current. The leading seaplane held on for perhaps five seconds, then like a wounded partridge, it began to dive towards the water. The pilot, retaining his presence of mind, righted his 'bus and allowed her to volplane, until the inventor trained the projector upon the second sea-plane. At the first sign of the ignition being cut out, the pilot banked steeply. The sudden swerve brought the seaplane outside the invisible beam. The twin motors picked up again. By this time Brian had recovered his composure. He was again an inventor, sure of himself, and tasting in full measure the joy of achievement, when not a moment before his sensations had been much like those of a nervous schoolboy faced by a tough "paper", and by no means confident of the result. The slightest deflection made it possible for the ray to hold the machine as surely as the spider's web does the enmeshed fly.