And so the weary watch went on. The wind, hitherto off-shore, had suddenly veered to the south-east and blew with considerable violence right in the teeth of the convoy. Even at reduced speed the Bolero was "shipping it green" right over her raised fo'c'sle, while stinging showers of icy spray lashed viciously against the canvas dodgers and rattled like hail against the plate-glass windows of the chart-house.
There was a marked change in the Sub's appearance, as he crouched under the lee of the dodger. His hitherto slim figure looked podgy, and for a good reason.
Underneath his great-coat he wore his monkey-jacket, three sweaters, and a muffler. Oilskin trousers tucked into and turned over the tops of his sea-boots, and a weather-beaten cap rammed well down over his eyes completed his watch-keeping kit. With him stood the signalman and quartermaster, both enveloped in duffel suits.
On deck everything was battened down, for the glass was falling rapidly and giving every indication of a sharp, if short, blow before very long. Already the wind was moaning dismally through the wireless aerials, and causing the bridge canvas to bag in a double series of almost inflexible bulges.
At six bells (10 p.m.) the signal was given to the convoy to alter course eight points to port. Then ensued an anxious time, some of the vessels obeying with alacrity, others dallying in the carrying out of their instructions. With the wind now abeam, the lumbering craft rolled horribly, while the long, lean destroyers, which largely rely upon steadiness by reason of their speed, were constantly rolling rail under. Torn clouds of reeking smoke from the vessels to windward, mingled with icy spray, swept over the Bolero, whose position on that account was the most undesirable of the escorting craft.
"It's Fritz's chance, absolutely," thought Alec. "A U-boat could be lying awash a cable's length away and we shouldn't spot her. And it's a dirty night to have to stand by a sinking tramp."
"There's something on our port bow, sir," reported the look-out, stretching a glistening oilskin-enshrouded arm in the direction indicated.
"Yes, by Jove," ejaculated Seton. "It's a dirty Fritz. Starboard two, quartermaster, and let her have it."
It was for one thing fortunate that the Bolero was running at greatly reduced speed, otherwise the lurking U-boat might have been passed unnoticed.
The submarine had evidently been compelled to rise to recharge batteries, the heavy sea notwithstanding. Her hydrophones had given indication of the presence of the convoy, and the latter's recent change of course had set the vessels slightly abeam and at gradually reducing distance. The kapitan-leutnant of the U-boat, quick to grasp the situation, had waited until the escorting destroyers on the convoy's port hand had passed, and was now manoeuvring to fire a torpedo at the rearmost tramp—which also happened to be the largest. Owing to the darkness it was almost impracticable to make use of the periscope, so the German submarine remained awash in order to take a direct bearing on her intended victim.