It was Roy who called his attention to it.

’Ken, there’s a thundering great fish out there.  Do they keep sharks in these waters?’

Before Ken could reply, the splash was followed by a slight grating sound, then a dull clank, like two metal plates being lightly struck together.

Hope dawned suddenly in Ken’s heart, sending a tingling shock through the whole of his perishing body.

‘That’s no fish,’ he muttered.  ‘That’s no fish.’  Then raising himself as high as he could out of the water he sent a sharp cry for help pealing through the darkness.

‘Hallo!  Hallo!  Who’s that?’

Never had Ken been happier to hear the sound of a human voice.

‘Three survivors from the “Maid of Sker,"’ he answered.  ’Our boat’s upset.’

‘Hang on!’ came the quick reply.  ‘We’ll have you out in a jiffy.’

There came low voiced orders, the low purr of an engine, and a low dark bulk topped by a curious square-looking turret came gliding towards them.

‘What is it?’ muttered Roy in a dazed tone.

‘A submarine,’ Ken answered gladly.  ’That’s her conning tower.  Here she comes.  Hang on to Gill, or the wash will take him off.’

A moment later, and the long gray craft swam up right alongside of the dinghy.  It was the most beautiful bit of steering imaginable.  A hand reached out and pulled the dinghy close against the hull, and strong arms gripped and lifted the three aboard.

Ken felt himself swung gently up the conning tower, then he was lowered with equal ease and skill through the open hatch.  Within an incredibly short time he was flat on a mattress laid on the throbbing steel floor of the submarine.

A keen-faced officer stood beside him.

‘Both the sweepers gone?’ he asked gravely.

’I’m afraid so, sir.  The “Swan” was knocked all to bits, and we saw the “Maid” sink.  I believe we are the only survivors.’

’We heard the firing, but couldn’t get here sooner.  But you’re in khaki.  How’s that?’

’Horan and I are escaped prisoners, sir.  We stole a boat up by Kilid Bahr, and were picked up by the “Maid.”  Gill is the only man left from the trawler.  He was one of the crew of the “Maid’s” dinghy that went to help the “Swan’s” people.’

‘And you?’

‘Horan and I were trying to save him when the “Maid” was hit.’

The other nodded approvingly.

’Ah, you’re Australians.  Good men!  But I see you’re about all in.  I shan’t bother you with any more questions now.  Williams, see these men have a change, and a tot of rum.  And some of you give ’em a good rub down.  They’re stiff with cold.’

He nodded again and went off.

Williams, a burly torpedo coxswain, at once took charge of Ken.  His big hands were as tender as a woman’s as he stripped off the boy’s soaking clothes and substituted for them a fresh suit of warm lammies.  Before putting them on, he gave Ken such a rubbing with a rough towel as sent the stagnant blood tingling through every vein.