The bright rays of the setting sun were shining over the valley of Ettrick, and lighting up the stone turrets on the old tower of Oakwood.

For many a long year the old tower had stood empty, while its owner, Sir Michael Scott, one of the most learned men who ever lived, wandered in distant lands, far across the sea.

He had been a mere boy when he left it, to study at Durham and Oxford: then the love of learning had carried him first of all to Paris, where he had been famed for his skill in mathematics; then to Italy, and finally to Spain, where he had studied alchemy under the Moors, and had learned from them, so 'twas said, much of the magic of the East, so that he had power over spirits, and could command them to come and go at his bidding, and could read the stars, and cure the sick, and do many other wonderful things, which made all men regard him as a wizard.

And now that he had come back to his old home once more, the country folk avoided him, and gazed with awe at the great square tower where, they said, he spent most of his time, practising his magic art, and holding converse with the powers of darkness.

The King, on the other hand, thought much of this most learned knight, and would fain have seen more of him at his court in Edinburgh, but Sir Michael loved the country best, and spent most of his time there, writing, or reading, or making experiments.

This evening, however, he was not in his tower, but was sitting by the side of the Ettrick, studying with deepest interest all the sights and sounds of nature which were going on around him. For he loved nature, this studious, quiet, middle-aged man, and the sight of the little minnows darting about in the water, and the trouts hiding under the stones, and the partridges coming whirring across the cornfields, gave him as much pleasure as all the wonderful sights which he had seen in far-off lands.

Suddenly he raised his head and listened. Far away in the distance he seemed to hear the sound of trumpets, and the "thud," "thud" of horses' hoofs, as if a body of men were riding quickly towards him.

"Some strangers are approaching," he said to himself, "and if I am not mistaken they are soldiers. I will hasten home and learn their errand. Mayhap it is a message from his Majesty the King."

He rose to his feet slowly, for his limbs were somewhat cramped with sitting, and walked with stately dignity to the tower.

The riders had just arrived, and, as he expected, they bore a message from the King. As he approached, a knight clad in full armour rode forward, preceded by a man-at-arms, and, bending low over his horse's neck, presented to him a parchment packet, sealed with the Royal Seal.

"The King of Scotland, whom God preserve, sends greetings to his loyal cousin Sir Michael Scott," he said, "and whereas various French sailors have committed acts of piracy on the high seas, and have attacked and robbed divers Scottish vessels, he lays on him his Royal commands that he will betake himself to France with all speed, and deliver this packet into the hands of the French King. And, further, that he will demand that an answer to the writing contained therein be given him at once, and that he hasten back with all dispatch, and draw not rein, nor tarry, till he deliver the answer to the King in Edinburgh."

Sir Michael took the packet from the messenger's hand and bowed gravely. He was accustomed to receive such orders, and everyone wondered at the marvellously quick way in which he obeyed them.

"Carry my humblest greetings to his Majesty," he answered, "and assure him that I will lose no time, but will at once set about making my preparations. By dawn of day I will be gone, mounted on the swiftest steed that ever the eye of mortal man gazed upon."

"Is it swifter than the horse which his Majesty keeps for his own use at Dunfermline?" asked the soldier curiously. "For if it is, it must indeed be a noble animal, and 'twould fetch a good price among the barons of the court. Ever since his Majesty has turned his mind so much to horses, his courtiers have vied with each other to see which of them could become the possessor of the swiftest animal."

"My horse is not for sale," said Sir Michael shortly, "not though men offered me his weight in gold."

The young officer bowed again. There was something in Sir Michael's tone which forbade him asking to see the horse, much as he should have liked to do so; so, giving a signal to his men, he turned his horse's head in the direction of Edinburgh, and rode off, leaving Sir Michael standing on the doorstep gazing after them, a strange smile on his face.

"A good price," he repeated; "by my troth, 'twould need to be a very good price which would buy my good Diabolus from me. But I must go and summon him."

Muttering strangely to himself, he turned and entered the tower.

He went up the narrow, winding, stone stairs until he reached a little iron-studded door. This door was locked, but he opened it with a key which hung from his girdle, and, entering the low-roofed attic-room to which it led, he locked it again carefully behind him. The attic was at the top of the tower, and through the narrow windows which pierced three of its walls, a glorious view was to be had over the surrounding country.

But Sir Michael had not come up there to admire the view; he had other work to do—work which seemed to need mysterious preparations.

First of all, he proceeded to dress himself in a curiously shaped black cloak, and a hunting cap made of hair, which he took down from a nail in the wall. The cloak was very long, and completely enveloped his figure, and, when he had pulled the hairy cap well down over his eyes, no one would have taken him, I warrant, for the quiet, middle-aged, master of Oakwood.

When he was dressed he took down a leaden platter from a shelf by the door, and, opening a cupboard, he took out a little glass bottle full of a clear amber-coloured liquid, which glowed like melted fire. Setting down the platter on a little round table in the middle of the room, he dropped one or two drops of this liquid on it, and in an instant they broke into tongues of flame which curled up high above his head.

It was a strange and weird fire, enough to frighten any man, but the still, dark-robed figure standing beside it never moved, not even when a number of tiny little imps appeared, clad in scarlet, and green, and blue, and purple, and danced round and round it on the table, tossing their tiny arms, and twisting their queer little faces, as if they had gone mad.

He waited patiently until the little creatures had finished their dance and disappeared, then he seized the platter, and, going to one of the narrow windows, he flung it open, and, pushing the platter through it, he threw it, with its burning load, far out into the gathering twilight.

He watched the fire as it fell, in glowing fragments, among the oak trees which surrounded the tower, then he opened a small, black, leathern-bound book, which lay chained to a monk's desk which stood in a corner. Opening it he read a few words in an unknown tongue, then he turned to the window again and waved a little silver wand over his head three times.

"Come, Diabolus. Come, Diabolus," he muttered, and then he knelt on the floor and waited eagerly, his eyes fixed on the Western horizon.

The sun had sunk, but the sky was clear, and one or two stars had appeared, and were shining out peacefully, like little candles set in a golden haze.

Presently, however, big black clouds began to appear, and pile up, one against another, till the little stars were blotted out, and the whole sky became as black as night.

In a little time the dull muttering of thunder could be heard far away over the woods. It came nearer and nearer—crash upon crash, and roar upon roar—while the lightning flashed, and a perfect tempest of wind arose and lashed the branches of the tall trees into fury. Truly it was an awful storm.

The wizard felt the solid masonry of the tower rock beneath him, but he was as calm as if only a little gust of wind had been passing on a summer's day.

Still he knelt on, peering eagerly into the darkness. At last his eyes grew bright and keen, for he saw a shadowy form come floating through the air, driven by the wind. He knew now that his charm had worked, and that this was his familiar spirit—the spirit over whom he had most control—who had come in the form of a great black horse, with flaming eyes, and flowing mane, to carry him over the sea to France.

With one bound he flew through the window, and alighted on its back.

"Now woe betide thee, Diabolus," he said, "if thou fliest not swiftly. For I must be in Paris by daylight to-morrow."

The huge black horse shook its mane, and snorted fiercely, as if it understood, and without more ado it flew on its way, its uncanny black-cloaked rider seated on its back.

As soon as they had disappeared, the storm died away, and the moon rose, and the little stars shone out over Oakwood Tower as clearly and quietly as if there had never been a cloud in the sky. Meanwhile Sir Michael Scott and his huge black charger were flying over hills, and valleys, and rivers, in the darkness. They even flew over the sea itself, and never halted until the day broke, and there, far below, lay the city of Paris, dimly seen in the gray morning light.

In the King's Palace the lackeys were hardly awake. They gazed at one another in astonishment when the heavy iron knocker on the great gate fell with a knock that echoed through the courtyard.

"Who dares to knock so loudly at this early hour?" asked the fat old porter in great indignation. "Whoever it be, I trow he may e'en wait outside till I have broken my fast."

But before he had done speaking the knocker fell once more, and there was something so commanding in the sound that the little man hurried off, grumbling to himself, to get the key.

"Beshrew me if it doth not sound like a messenger from some great king," said a man-at-arms who was standing by, and the porter's heart misgave him at the thought that perhaps by his tardiness he had got himself into trouble.

But when he opened the great door, instead of the company of armed men whom he dreaded to see, there was only a solitary rider, muffled in a great black cloak, and wearing a hairy cap drawn down over his face, seated on an enormous black horse. The stranger's dress was so outlandish, and his horse so big, that the porter crossed himself.

"Surely 'tis the Evil One himself," he muttered; and when the lackeys heard his words, they crowded round the doorway. They, too, were puzzled at Sir Michael's appearance, and began to laugh and jeer at him.

"He is like a hooded crow," cried one.

"Nay, 'tis an old wife in her husband's clothes," shouted another.

"Surely the cloak belonged to Noah," cried a third.

But they started back in dismay when the muffled figure pushed up his cap, and demanded an audience of the King.

"I come from the King of Scotland," he said haughtily, "and his business brooks no delay."

A shout of laughter greeted his demand.

"Thou a messenger from the King of Scotland!" they cried. "A likely story, forsooth! The King of Scotland sends not beggars, in old rusty suits, as his ambassadors. No, no, my good fellow, thou askest us to believe too much. Whatever thou art, thou art not a king's messenger."

"What!" cried Sir Michael. "Ye refuse to do my bidding! and all because I am not decked out in crimson and gold, and ridest alone without a retinue. Well, ye shall see that it is not always wise to judge of a man by his outward appearance. Make way there." And without wasting any more words, he leaped from his horse, and, throwing its bridle over a pillar, he strode right through the middle of them, and made his way to the King's private apartment, without even waiting to be announced.

Now the King of France was accustomed to be treated with great ceremony, and when this dark-robed man strode into his bed-chamber, and held out the parchment packet to him, demanding an instant answer, he was very indignant, and refused to open it.

"Thou sayest that thou comest from the King of Scots," he said. "Well, I believe thee not. If thou wert Sir Michael Scott, as thou sayest thou art, thou wouldst have come with an armed escort, as befitted thy rank and station. Therefore begone, Sirrah, and count thyself happy that I have not had thee thrown into one of the palace dungeons, as a punishment for thy insolence."

"By my troth," cried Sir Michael angrily, "if this is the way thou wouldst answer my master's demands, I trow I can soon bring thee to a better frame of mind."

Without waiting for an answer, he flung down the parchment packet on the floor, and strode out of the room in the same way that he had entered, leaving the angry King gazing after him in astonishment.

"The fellow is mad," he cried to the nobles who stood round. "See to it that he is shut up until he comes to his senses."

But Sir Michael had already reached the courtyard, and passed through the great door to where his horse was waiting outside. He lowered his voice and spoke gently to the mighty beast.

"Stamp, my steed, and show the varlets that we are better than we seem to be," he said. And at his bidding the gigantic creature lifted one of its forefeet, and brought it down with all its might on the pavement.

In an instant it was as though an earthquake were passing over the city. The great towers of the Palace which frowned overhead rocked and swayed, and all the bells on a hundred church steeples chimed and jangled, until the air was thick with the sound of them.

The King and his courtiers were very much alarmed at these strange events, but they did not like to own that it was the mysterious stranger who was the cause of them. All the same, the King called a hurried council, and when the nobles were assembled, and seated in their places in the great hall, he opened the parchment packet, and took out the papers which it contained. When he had read them his face flushed with anger. The King of Scotland's demands were very urgent, and moreover they were stated in no uncertain language, and as he considered that he was a much more powerful monarch than King Alexander, he did not like to be dictated to.

"Ah," he said, "so my Lord of Scotland lays down his own terms with a high hand. Methinks he must learn that this is not the way to obtain favours from France."

"Ay, so in good sooth he must learn," repeated the nobles in one breath. "And in order that the lesson be made plain, we advise that his messenger be cast into prison, and that no notice be taken of his requests."

"Your advice pleases me well," said the King. "Command that the officers seize the fellow at once. Certs, he may think himself lucky that We permit his head to remain on his shoulders."

The command was given, but Sir Michael had been growing more and more impatient that no more notice seemed to be taken of his errand, and when the officers of the guard appeared, and, instead of handing him the French King's answer, as he had expected, laid their hands on him to drag him off to prison, his anger knew no bounds.

"What," he cried, "doth the King still refuse to listen? By my troth, he shall rue the delay," and once more he whispered in the black horse's ear, and once more the mighty creature lifted its great forefoot and brought it down with a crash on the pavement.

The effect was even more terrible than it had been before.

In an instant great thunder clouds rolled up from the horizon, and a fearful storm broke over the city. The thunder rolled and the lightning flashed, and strange and weird figures were seen floating in the air. The great bells which hung in the steeple of the great Cathedral of Notre Dame gave one awful crash, and then burst in two, while the towers and pinnacles of the splendid church came tumbling down in the darkness. The very foundations of the Palace were shaken, and rocked to and fro, till everyone within it was thrown to the ground. The King himself was hurled from his throne of state, and was so badly hurt that he cried aloud with pain and fear.

As for the courtiers, they lay about the floor in all directions, paralysed with terror, crossing themselves, and calling on the Saints to help them. They were so terrified that not one of them thought of going to their Royal Master's aid.

The King was the first to recover himself. "Alack! alack!" he groaned, rising to his feet. "Woe betide the day that brought this fellow to our land! Warlock or wizard, I know not which, but one of them he must be, for no mere mortal man could have had the power to work this harm to our city."

While he was speaking a loud trampling of feet was heard outside the great hall, and all the lackeys came tumbling in, pell-mell, without waiting to do their reverence, just as if the King had been any common man.

"O Sire," they cried, "grant the fellow anything and everything he asks, and let him be gone. He threatens that he will cause this awful beast to stamp yet once again, and, if he does, the whole land of France will be ruined. If your Majesty but knew what harm hath been wrought in the city already!"

"Yes, let him begone," wailed the courtiers, slowly beginning to pick themselves up from the floor, and feeling their bones to see if any of them were broken.

And, indeed, the King was nothing loth to grant their request, for he felt that if the mysterious stranger were allowed to stand at the door much longer his whole kingdom would be tumbling to pieces about his ears. Better far that the King of Scotland should be satisfied, even although it was sorely against his inclinations.

With trembling fingers he picked up the papers and once more read them. Then he wrote an answer promising to fulfil all the Scotch King's demands and he sealed up the packet, and flung it to the nearest lackey.

"Give it to him and bid him begone," he cried, and a sigh of relief went round the hall, as a minute later the man returned with the tidings that the great black horse and its outlandish rider had vanished.

"Heaven grant that when next my Cousin of Scotland sends an ambassador, he choose another man," said the King, and there was not a soul in all the palace who did not breathe a fervent "Amen."

Meanwhile, Sir Michael and his wonderful steed were speeding along on their homeward way. They had crossed the north of France, and were flying over the Straits of Dover, when the creature began to think that it might work a little mischief on its own account.

It had taken a sudden fancy to remain in France for a while, and it thought how nice it would be if it could pitch its master, whom it rather feared than loved, over its head into the water, and so be rid of him for ever.

It knew that as long as it was under his spell, it had to do his bidding, but it knew also that there were certain words which could break the spell even of a wizard, and it began to wonder if it would be possible to make Sir Michael pronounce one of these.

"Master," it said at last slyly, for when it wanted it had the power of speech, "I know little about Scottish ways, but I have oft-times been told that the old wives and children there mutter some words to themselves ere they go to bed. 'Tis some spell, I warrant, and I would fain know it. Canst tell me the words?"

Now the wily animal knew perfectly well what words the children of Scotland were taught to repeat as they knelt at night at their mother's knee, but it hoped that its master would answer without thinking.

But Sir Michael had not studied magic for long years for nothing, and he knew that if he answered that the women and children in Scotland bowed their knees and said their Pater Noster ere they went to bed, the holy words would break the spell, and he would be at the mercy of the fiend, who, when he needed him, was obliged to take the form of a horse, or serve him in any other way which he required.

So he shook the creature's bridle and answered sharply, "What is that to thee, Diabolus? Attend to the business thou hast in hand, and vex not thy soul with silly questions. If thou truly desirest to know what the bairns are taught to say at bed-time, then I would advise thee, when thou art in Scotland, and hast time to spare from thy wicked devices, to go and stand by a cottage window, and learn for thyself. Mayhap the knowledge will do thee good. In the meantime think no more of the matter, unless thou wouldst feel the weight of my wand on thy flanks."

Now, if there was one thing which the great horse feared, it was the wizard's magic wand, so he put his mind to his work, and flew with all the swiftness he possessed northwards over England, and across the Cheviots, until at last they came in sight of Edinburgh, and the Royal Palace of Holyrood.

Here Sir Michael slid from his back, and dismissed him with a little wave of his wand. "Avaunt, Diabolus," he said, and at the words the magic horse vanished into thin air, and, strange to say, the black cloak and hairy cap which the wizard had worn on the journey seemed to fall from him and vanish also, and he was left standing, a middle-aged, dignified gentleman, clad in a suit of sober brown.

He hurried down to the Palace, and sought an instant audience of the King. The lackeys bowed low, and the doors flew open before him, as he was led into his Majesty's presence, for at the Court of Holyrood Sir Michael Scott was a very great person indeed.

But for once a frown gathered on King Alexander's face when he saw him. Kings expect to be obeyed, and he was not prepared to see the man appear whom he had ordered off to France with all speed the day before.

"What ho! Sir Michael," he said coldly. "Is this the way that thou carriest out our royal orders. In good sooth I wish I had chosen a more zealous messenger."

Sir Michael smiled gravely. "Wilt please my Sovereign Lord to receive this packet from the hand of the King of France?" he said with a stately bow. "Methinks that he will find that in it all his demands are granted, and that I have obeyed his behests to the best of my power."

The King was utterly taken aback. He wondered if Sir Michael were playing some trick on him, for it was absolutely impossible that he could have gone and come from France in twenty-four hours.

When he opened the packet, however, he saw that it was no trick. In utter amazement he called for his courtiers, and they crowded round him to examine the papers. They were all in order, and all the requests had been granted without more ado. Reparation was to be made for the damage that had been done to the Scottish ships, and in future all acts of piracy would be severely punished. It was evident that the papers had been taken to Paris, for there was the French King's own seal, and there was his name signed in his own handwriting, though how they had been carried thither so quickly, nobody ventured to say.

"'Tis safer not to ask, your Majesty," whispered one old knight, making the sign of the Cross as he spoke, "for there are strange tales afloat, which say that the Lord of Oakwood keeps a familiar spirit in that ancient tower of his, who is ready to do his bidding at all times; and, by my soul, this goes far to prove it."

The King looked round uneasily, in case Sir Michael had heard this last sentence. He felt that if this were true, and he were a wizard, as men hinted, it was best not to incur his displeasure; but he need not have been afraid. The Lord of Oakwood loved not courts, and now that he had done his errand, and the papers were safe in the King's hand, he had taken advantage of the astonishment of the courtiers to slip unobserved through the crowd, and, having borrowed a horse from the royal stables, he was now riding leisurely out of the city, on his way home to his old tower on the banks of the Ettrick.