“A skipper on one of the bigger passenger lines would be just as keen as you could be not to have his ship mixed up with anything discreditable.  But passengers are an impious lot.  They are just bursting for want of a job, most of them; they revel in anything like an accident to break the monotony; and if they can spot a bit of foul play—­or say they helped to spot it—­why, there they are, supplied with one good solid never-stale yarn for all the rest of their natural lives.  So you see they’ve every inducement to do a lot of ferreting that a ship’s officers (with other work on hand) would not dream about.”

Captain Kettle pulled thoughtfully at his neat red pointed beard.  “You’re putting the thing in a new light, sir, and I thank you for what you’ve said.  I see my course plain before me.  So soon as we have dropped the pilot, I shall go straight to this Mr. Cranze, and tell him that from information received I hear he’s going to put Mr. Hamilton over the side.  And then I shall say:  ’Into irons you go, my man, so soon as ever Hamilton’s missing.’”

Lupton laughed rather angrily.  “And what would be the result of that, do you think?”

“Cranze will get mad.  He’ll probably talk a good deal, and that I shall allow within limits.  But he’ll not hit me.  I’m not the kind of a man that other people see fit to raise their hands to.”

“You don’t look it.  But, my good sir, don’t you see that if you speak out like that, you’ll probably scare the beggar off his game altogether?”

“And why not?  Do you think my ship’s a blessed detective novel that’s to be run just for your amusement?”

Lupton tapped the table slowly with his fingers.  “Now look here, Captain,” he said, “there’s a chance here of our putting a stop to a murderous game that’s been going on too long, by catching a rogue red-handed.  It’s to our interest to get a conviction and make an example.  It’s to your interest to keep your ship free from a fuss.”

“All the way.”

“Quite so.  My Company’s prepared to buy your interest up.”

“You must put it plainer than that.”

“I’ll put it as definitely as you like.  I’ll give you L20 to keep your eye on these men, and say nothing about what I’ve told you, but just watch.  If you catch Cranze so clearly trying it on that the Courts give a conviction, the Company will pay you L200.”

“It’s a lot of money.”

“My Company will find it a lot cheaper than paying out L20,000, and that’s what Hamilton’s insured for.”

“Phew!  I didn’t know we were dealing with such big figures.  Well, Mr. Cranze has got his inducements to murder the man, anyway.”

“I told you that from the first.  Now, Captain, are you going to take my check for that preliminary L20?”

“Hand it over,” said Kettle.  “I see no objections.  And you may as well give me a bit of a letter about the balance.”

“I’ll do both,” said Lupton, and took out his stylograph, and called a waiter to bring him hotel writing paper.