supposed that Beau had!"
"How do you know?" I asked, aghast.
"By the way you looked at him--oh, half a dozen times."
"I had reason to suspect him," I said.
"What reason--except that you caught hold of his wrist in the dark, when he was probably doing just what you were doing, trying to catch Gussie in the act of putting it back?" asked Digby.
"I'd rather not say any more about it, Dig," I replied. "It's Beau's business after all, and . . ."
"Don't be a colossal ass," interrupted Digby. "Of course it's Beau's business, and that's what we are talking about. The more we both know, the more we can both help him--either to get away, or to come back. . . . If we knew he is guilty, which, of course, he isn't, we could draw red herrings across his trail; and if we knew he is innocent, which he is, we could lay for the real thief and catch him out."
"Beau doesn't want him caught out, evidently," said I.
"What--not if it's the miserable Gussie?" asked my brother indignantly.
"It isn't," said I. "And Beau knows it."
"Well--let's have those reasons, and we'll get to work," said Digby. "You needn't feel as though you were giving Beau away. There is no more harm in my knowing than in your knowing, and there may be some good. I am not asking you to tell Aunt, or the police, am I, bun-head?"
This was true enough. No harm could result from Digby's knowing all that I knew.
Moreover, if, as Digby assumed, Michael were shielding somebody else, presumably he would welcome any evidence that strengthened the case against himself.
"Well," said I reluctantly, "it's like this, Dig. . . . Beau went down to the drawing-room last night. I met him with the key in his hand . . ."
"And what were you doing, if one might ask?" interrupted my brother.
"Going to see if the 'Blue Water' had been returned," I replied.
"Anyhow, Beau hadn't returned it, had he?" grinned Digby.
"No--but at the time I, naturally enough, thought he had," said I, "and I suppose that fixed the idea in my mind. I first got the idea--naturally enough, again--when I caught his hand hovering over the glass cover in the darkness."
"Anything else?" asked Digby.
"Yes, the third reason I had for suspecting Beau--though I put my faith in him before all reason--was that I found him going to the brass box with a leather and duster to rub out the finger-prints he had made in taking and returning the key."
Digby whistled.
"Ingenious," he murmured. "As artful as our Auntie, if she had the idea. . . . Detectives would have the idea anyhow."
"I think she did have the idea," I said. "I believe she went straight from the drawing-room and polished all the finger-marks from the lid and front of the damned thing."
"And how do you know that Beau was on to the dodge?" asked Digby.
"He said so. He came into the hall with the cleaning-things in his hand, just as I was doing it myself."
Digby stared.
"Doing it yourself?" he said. "Why?"
"Oh, can't you see?" I groaned. "If Beau had been playing the wild ass, I didn't want his finger-prints to be found there, on top of the fact that I had been seen clutching his fist in the drawing-room."
"Yours were there as well as his," observed Digby, "if you went to the box for the key."
"Yes--they were," said I, "and they are there, alone, now."
"Stout fella," approved Digby. "I'll go and shove mine on too, and fog the Sherlocks. . . . But you really are a goat," he went on. "Don't you see that Beau was probably going to do precisely what you were doing? He was going to polish the beastly thing clean of all foot-marks, and then jab his own on."
"Why?" I asked.
"To shield the real culprit, of course," said Digby patiently.
"Yes--but why?" I repeated. "Why should Beau be a gratuitous ass and take the blame instead of--Gussie, for example? He'd have been more likely to nose him out and then slipper him well."
"Because he knew it wasn't Gussie," replied my brother solemnly.
"Who then?" I asked.
"He didn't know," answered Digby. "But isn't it as clear as mud, that since it wasn't Gussie or Isobel, it was you or me--or else Claudia?"
I was silent.
"Now look here, John," went on Digby. "'Nuff said, and time to do something instead. But first of all, do you still suspect Beau?"
"I have never suspected him," I replied. "I have only realised that I caught his hand, met him with the drawing-room key, and know he was going to rub finger-prints off the brass box."
"Plain yes or no," said Digby. "Do you suspect Beau?"
"Absolutely not," I said promptly. "No. No. No!"
"Very good then. Now--Did you do it?"
"I did not," said I.
"Nor did I. Very well! Since Isobel and Augustus mutually prove each other innocent, as she was holding his arm, yards from the table all the time--who is left?"
"Claudia?" said I unhappily.
"Now d'you get it?" smiled Digby, leaning back against the bottom of the bed, and clasping his hands round his knee.
"Good God, man," I cried, starting up. "You don't mean to tell me you suspect Claudia of jewel-stealing?"
"Keep calm," he replied. "I am not talking about whom I suspect. I am asking you who remains if you eliminate me and yourself as admittedly innocent, and Isobel and Augustus as proven innocent."
"Michael and Claudia!" I murmured. "Which idea is the more ridiculous?" I said aloud.
"Equally impossible," answered Digby. "Also the fact remains that it was one of those two--if it wasn't you. Furthermore, the fact remains that Michael has bolted for one of two reasons--because he is a frightened thief, or because he wished to shield the guilty person--you or Claudia."
A silence fell between us.
"I'm going dotty," said I at last.
"I've gone," said Digby, and we sat staring at each other.
After a time he rose.
"Got to get a move on," he said.
"What are you going to do?" I asked.
"Dunno," he replied.
As he was leaving the room
