he said carelessly.

"My dear Professor," replied Nicol Hendry a little coldly, "those who write stories about our profession always say that it is our invariable rule to suspect everybody, but we have a little common-sense, and we know the records of these ladies and gentlemen in the minutest detail from the Prince himself to Fraulein Hulda. We have not the slightest reason to suspect any of them."

"Ah, just so," said the other musingly; "no, of course you wouldn't have, and, unfortunately, I cannot tell you why you should. But I'll tell you this: if you ever do find cause to suspect any of these persons, you will find that this group is not complete. It ought to contain the photograph of Prince Oscar Oscarovitch."

"Prince Oscar Oscarovitch!" exclaimed Nicol Hendry, staring at him this time with wide-open eyes. "Why on earth should you----"

"Pardon me, my dear sir," interrupted Franklin Marmion gently, "remember that you are not supposed to care anything about the why or the how. I have already explained that I cannot explain."

"A thousand pardons, Professor. I don't often forget myself, but I did then. You took me so utterly by surprise."

"I fancy that you will be a good deal more surprised before you have come to the end of this affair," was the smiling but almost exasperating reply; "but, as I implied, I can only give you clues. I cannot even tell you how I get them, and it is for you to follow them or not as your judgment dictates. Now, here are one or two to go on with. Try and find out whether or not there was a four-funnelled Russian destroyer anywhere in the neighbourhood of Trelitz on the night of the 6th. Trace as closely as you can the movements of Prince Oscarovitch on that and the two preceding days. Try and find out whether or not a large closed chariot something like a barouche, drawn by four black horses, went from anywhere in the direction of the Castle on that day. And lastly, keep a very close eye upon the Egyptian Adept, as he calls himself--his name is Phadrig Amena--who worked those alleged miracles at my daughter's garden-party the other day. The Prince practically invited himself, and brought this fellow with him. If you can find out the true relationship between them I think you will have found out enough to keep you rather busy for the present. If you do think anything of these little points and examine them, let me know how you get on. We are going abroad for a bit of a holiday, but I will send you my address every now and then.

Now, let us go back into the drawing-room, and my daughter will give us some tea."

When Nicol Hendry left "The Wilderness" that afternoon he was about the most mystified man in London. After he had gone, Franklin Marmion said to Nitocris:

"Well, Niti, what do you think of our gimlet-eyed friend? Will he do?"

"Yes, Dad; I like his manner, and he seems very clever in his own way.

Quite a gentleman, too," she replied.

"I'm glad you think that," he added; "but what a pity it is that we could not get the world to accept fourth dimensional evidence without turning the said world inside out. We could clear up the whole _affaire_ Zastrow in a week then."

"But we shouldn't enjoy our holiday as much, I'm afraid, it would be too exciting," concluded Nitocris.

CHAPTER XVIII

MURDER BY SUGGESTION

Two days later the Marmions left London for Copenhagen, whence they intended to take a trip among the Baltic Islands, now looking their brightest and prettiest, then up along the Norwegian Fiords, just before the tourist rush began, and finally across from Trondjem to Iceland.

They were both excellent sailors, and both disliked crowds, especially when the said crowds were pleasure-hunting. Moreover, they had now a particular reason for being alone that they might enjoy together--they, the only two mortals who could do so--the countless marvels of that new existence which had now become possible for them. Where, too, could they do this to more advantage than in the ancient Northland, whose marvellous past would now be to them even as the present of their own temporal lives?

The Van Huysmans, and, of course, Lord Lester Leighton, were to remain in London until the end of the Season. Uncle Ephraim had cabled warm congratulations and large credits, and so Brenda, very naturally as a newly-engaged girl and a prospective Countess, wanted all that London and Ranelagh and Henley, Ascot and Goodwood and Cowes, could give her before her devoted lover's yacht carried them off to the Mediterranean.

Later in the autumn they were all to go over to the States to spend the winter in Washington and New York, whence they were to return to London for the wedding in May: surely as pleasant a programme--I fear that Miss Brenda spelt it "program"--as could be desired even by a fair maiden upon whom the kindly Fates had already showered their choicest gifts.

The only bitter drop in the family cup of content was the fact that Professor van Huysman was as far away as ever from the exposure of the fallacy which, as he was immovably convinced, those abominable demonstrations _must_ contain.

After due consultation between Nicol Hendry and his colleagues of France, Germany, and Russia, it was decided to follow up the clues which he had so mysteriously received. The others would, of course, have been very glad to know where and how he got them, but at the outset he had put them on their honour not to ask, and so professional etiquette made it impossible for them to do anything but accept his a.s.surance that he had received them from a source which was quite beyond reproach. Once they accepted the situation, they got to work with a quiet thoroughness which resulted in the spreading of an invisible but unbreakable net round the footsteps of every one of the suspects from the great Oscarovitch himself to the humble seller of curios in Candler's Court, and his still humbler friends Pent-Ah and Neb-Anat, who were known to the few who knew them as Mr and Mrs Pentana, renovators, and, possibly manufacturers, of ancient gems and relics.

But to one pair of eyes, at least, the police-net was as plainly visible as a spider's web hanging in the sunlight.

Within three days Phadrig received a visit from a shabbily-dressed but well-to-do Jew trader with whom he had done business before, who wanted to know if he could put him in the way of getting some really good old Egyptian gems and jewellery to show on approval to a wealthy patron who wanted to give his daughter a set of rare and uncommon ornaments on her wedding day. It was by this means, by acting as an intermediary between those who had something to sell and those who wished to buy, that Phadrig was supposed to make his modest living. His knowledge of Eastern antiquities was admittedly great, though, of course, no one knew how great, and he had often been asked why, instead of living in such a wretched way, he did not start a little business for himself; to which he always replied that he had no capital, and that he preferred independence, however poor, to the cares and ties of regular trading.

When the Jew had stated his business, Phadrig looked at him with sleepy eyes with a strange expression in them which, for some reason or other, held his visitor's usually shifty gaze fixed, and said in a slow, gentle voice:

"It is very kind of you, Mr Josephus, to bring me all these nice little commissions. They are of much benefit to a poor student of antiquities like myself, although I do not like trading in things that I love.

Still, one must live if one would study. Now, I had a gem sent to me the other day which I would dearly love to possess, but, alas! as well might I long for the Koh-i-Noor itself. Moreover, it is already promised--nay, as good as sold. But what have the poor to do with such splendours save to help the rich to buy them!"

The Jew's prominent eyes shone with an inward light at the mention of the gem, and he said in a coaxing voice:

"My dear Phadrig, we have always been friends for ever so long, and you say I've been a good customer to you. Might I have a look at that gem?

You know how fond I am of the pretty things. Have you got it here?"

"Yes, and you shall see it with pleasure, my good Josephus," replied Phadrig, well knowing the thought that was in his mind when he asked if he had the gem there in that shabby, unprotected room.

He went to the old oak secretaire, unlocked a cupboard at the side, and then a drawer within it, followed in every motion by the gleaming eyes of the Jew, and took from it a leather parcel. He undid this and produced a box, about four inches long and three wide, of plain black polished wood. It looked solid, but Phadrig made a swift motion with his fingers, and one half of it slid off the other. He held it towards his visitor, and said:

"What do you think of that as a specimen of ancient art, Mr Josephus?"

The Jew looked. The inside of the box seemed filled with green light tinted with yellow. Out of the midst of it began to shine a deeper green light which crystallised into the most glorious emerald that he had ever even dreamt of. It was fully an inch square, flawless, and of perfect colour. The yellow sheen came from a framework of heavy, exquisitely-wrought gold. Phadrig took it out and held it before him, and the green light seemed to radiate through the dull atmosphere of the room. The Jew stared at it with bulging eyes and trembling under-lip, and his hands went out towards it with a gesture which seemed like worship.

"G.o.d of Israel," he gasped, "was anything so splendid ever seen before!

Mr Phadrig, is it--is it real?"

"Real?" echoed the Egyptian scornfully. "Did you ever see light like that come out of a sham stone? You should know more about gems than that, Mr Josephus."

"Ah yes, yes, of course. It is glorious; it is worthy to shine on the breastplate of the High Priest--and what a price it must be! Is it allowed to ask the name of the great millionaire for whom it is destined?"

"Yes. It will in a few hours be the property of Prince Oscar Oscarovitch."

As Phadrig spoke he hid the gem in his hand. His voice was so changed that the Jew looked up at him. His eyes were wide open now, and glowing with a fire that made them look almost dull red. They seemed to see right through his eyeb.a.l.l.s and look into his brain. Josephus started as though he had been struck. He tried to turn his head away, but the terrible eyes held him. His fat, greasy, olive face grew grey and dry, and his head shook from side to side.

"What is the matter, my dear Mr Josephus?" asked Phadrig, in slow, stern tones. "The mention of the Prince seems to have affected your nerves.

Are you acquainted with His Highness?"

"Me? I? Why, how should I know a great man like the n.o.ble Prince? No, no; of course I know him as a very grand and great gentleman, but that is all, really all, my dear Phadrig."

"Yes, yes, of course," said the Egyptian, once more in his gentle voice; "would not be likely, would it? Now, if you would like to look at the gem more closely, go and sit down there by the light and take it in your hand. You will see that it is engraved with hieroglyphics. They say that this jewel was once the property of Rameses the Great of Egypt, and was given by him to his daughter Nitocris."

This information did not interest the Jew in the slightest, since he had never heard the names in his life; but the delight and honour of holding such a glorious gem in his hand even for a few minutes was ecstasy to him. He sat down, and held out his fat, trembling hand greedily. With a smile of contempt Phadrig placed the jewel in it, and said:

"Examine it closely, my friend. It is well worth it, and it may be long before you see another like it."

"Like--like _it_, like _this_! By the beard of Father Moses, I should think not--I should think--I should--oh, beautiful--glor--glorious--splendid--did--splen--oh, what a light--li--light--li--oh----!"

As each of the disjointed syllables came from his shaking lips he mumbled more and more, and his head sank lower towards the priceless thing in his palm. As he gazed, the stone grew round and bigger and brighter, till it seemed like a great green-blazing eye glaring into the utmost depths of his being. Then the light suddenly went out, his head fell on his breast, and as his hand sank, Phadrig caught it and took away the jewel. Then he put the Jew back in the chair, and standing in front of him began in a slow, penetrating voice:

"Isaac Josephus, thou hast gazed upon the Horus Stone, and he who doeth that may not answer the questions of an Adept with lies save at the price of his life. Now answer me truly, or to-morrow morning those of thine household shall find thee dead in thy bed."

Wide open the eyes of the hypnotised man stared at him, and the loose lips quivered, but these were the only signs of life.

"Thou art not only a dealer in gems and curious things: thou art also a spy of the police; is not that so?"

"Yes."

"Believing that I am a very poor man, yet knowing that I dealt with objects of value, they thought me to be one who receives such things from thieves to sell them again, since they could not. Is that so?"