But, unfortunately, the Knat carried no anti-aircraft guns, and by no possible exercise of ingenuity could the machine-guns, mounted as they were, be made to fire in a vertical direction. So Lawless had to gnash his teeth and watch the airship floating overhead within easy range, yet as safe, so far as he was concerned, as though she were five miles up.
"There goes my thousand quid, so close that I could almost touch her," he said bitterly to Trent. "Isn't it just my luck?"
"Pity we didn't think to rig up one of our Q.F's vertically," remarked the Sub-Lieutenant. "We could easily have done it."
Lawless turned his back on him in disgust. It was quite true that they might have done as Trent suggested, but the idea had not previously occurred to him. It was too late now, for it would take at least half a day to accomplish, and the Zeppelin could hardly be expected to wait complacently while those below made ready for her destruction.
Suddenly there was a loud explosion just to starboard of the destroyer, and a column of water arose so close that, in subsiding, it washed over the deck.
"By Jove, she's dropping bombs!" exclaimed Lawless, at the same time ringing down "Full-speed" to the engine-room.
However, in a few moments they had passed out of danger, and the airship was lost in the mist. The firing to the north-west still continued, though with decreasing vigour, as if fewer ships were engaged. This suggested to Lawless that some of the enemy vessels were drawing off, in which case he might possibly meet one or more on their flight back to the fastnesses of Heligoland.
"This is where we keep our eyes skinned and stand-by for trouble," said the Lieutenant as he reduced speed again. "See anything, Trent?"
"Not yet," answered the latter, who was straining his eyes in an endeavour to penetrate the fog.
About ten minutes afterwards there came the heavy thud of ship's engines going at full speed, though as yet nothing could be seen of the ship itself. The situation for those on board the Knat was one of infinite peril, for they did not know from one moment to another when, from out of the enveloping fog, a great towering mass might hurl itself upon their frail craft and send it to the bottom. Yet for obvious reasons Lawless dared not make any signal or betray his presence to the unknown monster advancing at, probably, between thirty or forty knots an hour.