"By a supreme feat of contortion she complied with his request, and glaring at her wrathfully the Professor removed his net and killing-bottle.
"'Six sofas in this room', he rumbled, 'and you must needs choose this one!'
"'How dare you call me woman!' she said shrilly.
"'I thought you were one,' he answered calmly, 'but you know best. Anyway, whatever you are, there's no cause to break my butterfly-net.' He placed it carefully in a corner and began wandering round the room inspecting the pictures. And he was keeping up a running commentary on the unspeakable manner in which they were hung when his host entered with a large revolver in his hand. The ladies shrieked, but Sir Rube held up his hand reassuringly.
"'Please do not be alarmed', he remarked. 'I am just going to say a few words, if I may, for the benefit of those of you who do not know the facts. This evening at dinner the note which I received upset me greatly. It was from a man who has been annoying me considerably for some months past: a man, I may say, who imagines he has some grudge against me. Now, since this note was delivered by hand, the assumption is that the man is about the place. He dared me, you may remember, to carry out the little ceremony of handing round the great Magor diamond. Had it not been for this note I should have postponed it till the last evening of your visit; as it is, however, I propose to kill, if I can, two birds with one stone.
"'Knowing this man to be a desperate character, I think it more than likely that he will make some attempt at a hold-up. He is probably hoping that the effect of his note will be exactly what we are going to let it be. Bluff, you perceive, of the second degree. Now then—what will occur if my surmise is correct? He will enter by the window, which we will open to its full width, and cover us with his revolver. We shall all put up our hands, and at that moment my three men who are hidden on each side of the window will collar him from behind.'
"'That's all very well,' said the Professor, nervously, 'but supposing he lets off his gun? He might hit somebody.'
"'Don't you worry about that, Professor,' laughed Sir Rube. 'My men will see to that. And if there is any trouble, there is always this.' He patted his own revolver significantly. 'Now we will start. But there is one thing I beg of you, ladies—try to appear quite natural. Don't keep glancing at the window, or anything of that sort, or it may give the show away. Leader, would you mind opening it as wide as you can? Thank you. Now if we form a circle: that's right.'
"He placed his revolver on a table behind the cabinet, so that it was quite invisible from the window; then with a flourish he opened the lid. 'The great Magor diamond, ladies and gentlemen,' he said grandiloquently, but, in spite of his warning to the others, his eyes kept darting towards the window. 'The largest and most perfect stone in the world.'
"He picked it up on its velvet stand and with a low bow presented it to Lady Shotover. 'Take it in your hands and feel the weight, dear lady,' he cried. And then in an undertone he added: 'I'm getting back to my revolver.'
"It passed from hand to hand, and everybody dutifully gave forth gurgles of wonder and delight, though it was noticeable that it moved with a rapidity that suggested a red hot stone. No one had the slightest wish to be the temporary possessor of it when the expected visitor materialised. Until, that is, it came to the Professor, who was beyond any thought of such a trifle as the Magor diamond. One of the girls had put it in his hand, but he was quite unconscious of it. For he was staring at a spot on the carpet opposite him, and his eyes were almost coming out of his head.
"'Look,' he whispered hoarsely. 'Heavens! but it is. I know it is. Here, take the bauble.' He literally threw the diamond at Mrs. Maddox, who was sitting next to him, leaped like a maniac for his butterfly-net, and the next moment with a sweep he brought it down on the floor.
"'It is!' he shrieked in an ecstasy, examining the net. 'The killing-bottle! Give me the killing-bottle!'
"'What on earth is it?' cried his host irritably.
"'The killing-bottle! cried the Professor. 'Hurry! hurry!' Somebody gave him the bottle, and with infinite care he inserted it under the net. 'A Death's Head moth,' he explained. 'And a perfect specimen. What luck! What incredible luck!'
"He straightened up and beamed on the company.
"'What a ridiculous fuss to make over a butterfly!' said Mrs. Maddox acidly, but the Professor was impervious to insult. With his killing-bottle in his hands he sat crooning gently to himself, whilst every now and then he held it up to the light to examine it better.
"'After which entertaining interlude,' remarked his host sarcastically, 'we might perhaps return to the trifling subject of my diamond.'
"Mrs. Maddox was still holding it, and once more it started on its round, amidst a chorus of praise. But somehow it rang a little flat; the solemnity of the moment had been spoiled. And Sir Rube, quite justifiably, felt ruffled. Why the deuce did the little fool want to go prancing after a wretched moth in the middle of the ceremony?
"The diamond came to Aaronhaus. Now, at any rate, would come the real appreciation of an expert. 'What do you think of that, my boy?' he said complacently. 'Something like a diamond—what?'
"The Jew looked at it; then at his host. 'Very like it.' he agreed courteously. 'Of course, my dear Jenkins, I should have realised that with the possibility of this man trying to get your stone you would take additional precautions. Still, I congratulate you, I must say.' He examined it again critically. 'Perfect,' he remarked.. 'Perfect. Who did it for you?'
"A sudden silence settled on the room. 'What the hell are you talking about? said Sir Rube thickly.
"'This,' said the Jew. 'It's paste, and very perfect paste. And I wondered who had done it.'
"'You lie!' roared his host, snatching it out of the Jew's hand. He examined it himself; then he let it drop on the floor.
"'By God!' 'he said softly, 'you're right!' His eyes roved round the silent circle of people, and there was murder in them. Sir Rube Jenkins of Mexbridge Towers had departed; Rube Jenkins of the mining camp had taken his place. 'Which of you—did it?' he said even more softly.
"Lord Shotover rose to his feet. 'We have the misfortune to be your guests,' he remarked icily.. 'And as their temporary spokesman I have the honour to inform you that a man who can use the word you have just used in the presence of ladies is a cad and an outsider of the first water.'
"'Maybe,' said the other thickly, picking up his revolver. 'But no one leaves this room till my diamond is handed back. I'll give the culprit half a minute: if it's not forthcoming by then, I send for the police.'
"'What exactly is your accusation? demanded Colonel Maddox.
"'A very simple one,' said the other. 'In the course of my diamond being handed round, somebody has substituted this paste thing for it. Where is the real one?'
"'Probably in that ridiculous bottle of the Professor's,' said Mrs. Maddox venomously.
"One of the girls gave a nervous little laugh, and then gasped. For the entire room was staring at Professor Rankel, whose face had gone the colour of putty.
"'Ridiculous,' he spluttered. 'Absurd.' He clutched the bottle even tighter as Sir Rube advanced towards him. 'I tell you it is absurd!' he cried shrilly.
"'You look as if it was,' snarled his host, levelling his revolver at the Professor's head. 'Give me that bottle!'
"He snatched it from the other's hands, opened it and turned it upside down. And there fell out a very dead moth and the great Magor diamond.
"'You dirty little thief,' said Sir Rube softly as he picked it up. 'So that is why you were prancing round with a butterfly-net.' And then he broke off abruptly, and peered at the diamond. 'But I don't understand,' he stuttered. 'This is paste too!' And even the so-called Professor looked astounded.
"'Am I going dippy?' Sir Rube cried. 'Look, Aaronhaus! That's paste, isn't it?'
"'It