"hello, sparks; you look a bit off colour?"

this was dr. selwyn's greeting as mostyn, having handed over the watch to plover, walked into the doctor's cabin.

"i feel it, doc," replied peter. "touch of the old complaint—malaria."

selwyn had detected the symptoms the moment the wireless officer showed his face inside the door. peter was trembling violently. he was feeling horribly cold, and his head was aching badly.

"taken any quinine?" asked the medical man.

"yes," was the reply. "my ears are buzzing already."

"then turn in," ordered selwyn. "i'll make you up a draught. keep as warm as you jolly well can. this will make you perspire freely before midnight, and you'll be fit by this time to-morrow."

peter waited while the doctor made up the medicine, and then staggered to his cabin, where mahmed, greatly concerned, helped his master into bed and piled blankets and a bridge-coat upon his shivering body.

it was now one bell in the first dog watch.

at two bells peter was still awake and trembling with cold spasms when watcher plover hurriedly entered the cabin.

plover had no idea that mostyn was down with malaria, and it was not unusual for him to find peter lying on his bunk when off duty.

"call for the ship, sir," he reported. "no bloomin' error this time. svp as sure's my name's plover."

mostyn kicked off the blankets and rolled out of the bunk. he staggered as he stood up, and would have been glad of plover's assistance. but the watcher, having delivered his message, had gone back to his post.

with a terrific buzzing in his ears peter almost dragged himself along the alleyway and up the bridge-ladder. many a time he had regretted the absence of a second wireless officer. now, above everything, he wanted an efficient substitute; but, of course, none was available.

entering the wireless-cabin, he picked up the telephones and gave the acknowledgment. then, a pencil in his trembling hand, he waited for the text of the message to come through:

"sw. tlb. few. cni. tlxq. vp aeld tni pu. aemq".

yes, peter had that all right, but, ever on the cautious side, he asked for the message to be repeated.

"here you are," he said, handing the duplicate message to his assistant. "nip off with that to captain bullock."

"don't you look rummy, sir?" remarked plover, noting for the first time mostyn's drawn features.

"am a bit," admitted peter. "i'll be all right by the morning. skip along."

watcher plover "skipped along" at his usual stolid pace to the old man's cabin, while peter, almost incapable of controlling his trembling limbs, somehow contrived to regain his bunk.

"signal just come through, sir," reported plover, as he handed the pencilled form to the skipper.

"all right," replied the old man brusquely. "hand me that book; the second on the left. that'll do, carry on."

it did not take captain bullock long to decode the message, but a frown of perplexity spread over his forehead as he read the momentous words.

then he rang the bell and ordered plover to return.

"who received this?" he asked.

"mr. mostyn, sir; he had the signal repeated."

"all right. you may go."

the assurance that the wireless officer had personally taken down the code message removed all doubts from captain bullock's mind.

"mr. preston," he sang out.

"ay, ay, sir,"

"fresh orders," announced the old man. "here you are: 'i have received telegraphic instructions from your owners for you to proceed straight to bulonga, where you will unload steelwork, proceeding thence to port sudan'. bring me the chart of the mozambique coast, preston, and let's see where we are—and the sailing directions while you are about it."

the acting chief hastened to fetch the required articles.

"bulonga—that's in mozambique," commented the old man. "what the blazes the kilba protectorate people want to have the steelwork dumped there for goodness only knows. however, it's my place to carry out instructions, mr. preston."

"ay, ay, sir," concurred the acting chief without enthusiasm. he had no love for the portuguese east african ports. a long spell there meant mosquitoes; mosquitoes meant malaria and other evils in its train. and there was simply nothing to see or do in these ports. preston had "had some" before to-day.

"they give no reason for the alteration, sir?" he inquired. "i suppose by any chance we haven't got the signal incorrectly?"

"no reason, mr. preston," replied captain bullock. "and here is the signal in duplicate. mostyn took that precaution, so i can stake my boots on its accuracy."

the two officers spent some time in poring over the chart and reading up the description of bulonga harbour and its approaches, as set down in the admiralty sailing directions for the east coast of africa.

"it'll be a tight squeeze for our draught," commented the skipper. "it'll mean a portugee pilot, worse luck. i know those gentry of old. i hope there's a british agent there to take over the brocklington company's consignment."

had captain bullock known that peter was down with a severe bout of malaria he would not have wagered his footgear so readily, for mostyn had made a mistake in taking in the signal. more, he had duplicated the mistake when he received the repetition at his own request.

with his head buzzing like a high-pressure boiler peter had read d (—..) for b (—...), his temporarily disordered sense of hearing failing to detect the slight but important difference.

consequently, instead of the west barbican shaping a course for rangoon, which in the code signal appeared as aelb, she was making for the comparatively unimportant harbour of bulonga (aeld).

the while ludwig schoeffer's seven-day watch was silently ticking out the seconds, minutes, and hours in the west barbican's baggage hold. the german agent was sublimely ignorant of the change in the ship's plans. he was still at durban, awaiting the news that the west barbican was overdue and believed missing. he would have been considerably surprised had he known that there was every likelihood of the ship sinking in bulonga harbour, where at low tide she would have barely enough water to lie alongside the quays.

if he had only known the vital difference that the omission of a "dot" in the spurious signal was to cause!