“Heard all about this discovery of those missing Saxonsteade diamonds?” he asked as he and Bryce picked up their knives and forks.  “Queer business that, isn’t it?  Of course, it’s got to do with those murders!”

“Think so?” asked Bryce.

“Can anybody think anything else?” said Sackville in his best dogmatic manner.  “Why, the thing’s plain.  From what’s been let out—­not much, certainly, but enough—­it’s quite evident.”

“What’s your theory?” inquired Bryce.

“My stepfather—­knowing old bird he is, too!—­sums the whole thing up to a nicety,” answered Sackville.  “That old chap, Braden, you know, is in possession of that secret.  He comes to Wrychester about it.  But somebody else knows.  That somebody gets rid of Braden.  Why?  So that the secret’ll be known then only to one—­the murderer!  See!  And why?  Why?”

“Well, why?” repeated Bryce.  “Don’t see, so far.”

“You must be dense, then,” said Sackville with the lofty superiority of youth.  “Because of the reward, of course!  Don’t you know that there’s been a standing offer—­never withdrawn!—­of five thousand pounds for news of those jewels?”

“No, I didn’t,” answered Bryce.

“Fact, sir—­pure fact,” continued Sackville.  “Now, five thousand, divided in two, is two thousand five hundred each.  But five thousand, undivided, is—­what?”

“Five thousand—­apparently,” said Bryce.

“Just so!  And,” remarked Sackville knowingly, “a man’ll do a lot for five thousand.”

“Or—­according to your argument—­for half of it,” said Bryce.  “What you—­or your stepfather’s—­aiming at comes to this, that suspicion rests on Braden’s sharer in the secret.  That it?”

“And why not?” asked Sackville.  “Look at what we know—­from the account in the paper this morning.  This other chap, Glassdale, waits a bit until the first excitement about Braden is over, then he comes forward and tells the Duke where the Duchess’s diamonds are planted.  Why?  So that he can get the five thousand pound reward!  Plain as a pikestaff!  Only, the police are such fools.”

“And what about Collishaw?” asked Bryce, willing to absorb all his companion’s ideas.

“Part of the game,” declared Sackville.  “Same man that got rid of Braden got rid of that chap!  Probably Collishaw knew a bit and had to be silenced.  But, whether that Glassdale did it all off his own bat or whether he’s somebody in with him, that’s where the guilt’ll be fastened in the end, my stepfather says.  And—­it’ll be so.  Stands to reason!”

“Anybody come forward about that reward your stepfather offered?” asked Bryce.

“I’m not permitted to say,” answered Sackville.  “But,” he added, leaning closer to his companion across the table, “I can tell you this—­there’s wheels within wheels!  You understand!  And things’ll be coming out.  Got to!  We can’t —­as a family—­let Ransford lie under that cloud, don’t you know.  We must clear him.  That’s precisely why Mr. Folliot offered his reward.  Ransford, of course, you know, Bryce, is very much to blame—­he ought to have done more himself.  And, of course, as my mother and my stepfather say, if Ransford won’t do things for himself, well, we must do ’em for him!  We couldn’t think of anything else.”