"You've turned your back on Mesopotamia, boys," exclaimed the licensed jester of the company. "Now you've the Mess-up-at-homia, an' so make the best of it. Blimy, wot's this comin'; a bloomin' Zeppelin!"
"Where?" exclaimed a dozen voices.
Following the direction of the speaker's outstretched hand Malcolm had his first view of an airship. It was not a large craft as airships go. Underneath its silver-grey envelope hung a small car like the fuselage of an aeroplane. As it approached, the whirring circle of a single, two-bladed propeller could be discerned. It was a "Blimp", or dirigible observation balloon.
The airship was flying rapidly "down wind" at an altitude of about two hundred feet. As it passed almost overhead the fuselage appeared to scrape the Pomfret Castle's main truck by inches. Presently the Blimp swung round and faced the wind, keeping on a course slightly diverging from that of the convoy. Plugging away dead in the eye of the wind its progress was not more than twenty miles an hour "over the ground", which in reality was a portion of the English Channel.
Suddenly the Pomfret Castle starboarded helm and broke out of line. The alteration of course had the effect of causing the huge vessel to list outwards. As she did so a long trail of foam almost parallel to the starboard side of the ship shot ahead until it was lost to sight in the distance.
For some moments not a single man moved. Attention had been shifted from the Blimp to the milk-white track in the water--the wake of the torpedo.
Only by prompt use of her helm had the Pomfret Castle escaped destruction. Even in home waters she had to run the gauntlet, despite the encircling line of destroyers.
With the utmost audacity a U-boat had lain submerged across the track of the convoy, trusting to be able to launch her bolt and disappear before even the swift destroyers could take her bearings, and close upon the spot where the tips of her periscopes had appeared when the torpedo had been discharged.
She had seen the escorting vessels and had taken the risk, but she had reckoned without the far-seeing eyes of the Blimp.
Already the airship had spotted a dark elongated shape beneath the waves. Invisible when viewed at a narrow angle to the surface, the submarine stood out clearly against the grey waste of waters when seen from above.