When old Mr. Salton had retired for the night, Adam and Sir Nathaniel returned to the study. Things went with great regularity at Lesser Hill, so they knew that there would be no interruption to their talk.

When their cigars were lighted, Sir Nathaniel began.

"I hope, Adam, that you do not think me either slack or changeable of purpose. I mean to go through this business to the bitter end-- whatever it may be. Be satisfied that my first care is, and shall be, the protection of Mimi Watford. To that I am pledged; my dear boy, we who are interested are all in the same danger. That semi- human monster out of the pit hates and means to destroy us all--you and me certainly, and probably your uncle. I wanted especially to talk with you to-night, for I cannot help thinking that the time is fast coming--if it has not come already--when we must take your uncle into our confidence. It was one thing when fancied evils threatened, but now he is probably marked for death, and it is only right that he should know all."

"I am with you, sir. Things have changed since we agreed to keep him out of the trouble. Now we dare not; consideration for his feelings might cost his life. It is a duty--and no light or pleasant one, either. I have not a shadow of doubt that he will want to be one with us in this. But remember, we are his guests; his name, his honour, have to be thought of as well as his safety."

"All shall be as you wish, Adam. And now as to what we are to do? We cannot murder Lady Arabella off-hand. Therefore we shall have to put things in order for the killing, and in such a way that we cannot be taxed with a crime."

"It seems to me, sir, that we are in an exceedingly tight place. Our first difficulty is to know where to begin. I never thought this fighting an antediluvian monster would be such a complicated job. This one is a woman, with all a woman's wit, combined with the heartlessness of a COCOTTE. She has the strength and impregnability of a diplodocus. We may be sure that in the fight that is before us there will be no semblance of fair-play. Also that our unscrupulous opponent will not betray herself!"

"That is so--but being feminine, she will probably over-reach herself. Now, Adam, it strikes me that, as we have to protect ourselves and others against feminine nature, our strong game will be to play our masculine against her feminine. Perhaps we had better sleep on it. She is a thing of the night; and the night may give us some ideas."

So they both turned in.

Adam knocked at Sir Nathaniel's door in the grey of the morning, and, on being bidden, came into the room. He had several letters in his hand. Sir Nathaniel sat up in bed.

"Well!"

"I should like to read you a few letters, but, of course, I shall not send them unless you approve. In fact"--with a smile and a blush--"there are several things which I want to do; but I hold my hand and my tongue till I have your approval."

"Go on!" said the other kindly. "Tell me all, and count at any rate on my sympathy, and on my approval and help if I can see my way."

Accordingly Adam proceeded:

"When I told you the conclusions at which I had arrived, I put in the foreground that Mimi Watford should, for the sake of her own safety, be removed--and that the monster which had wrought all the harm should be destroyed."

"Yes, that is so."

"To carry this into practice, sir, one preliminary is required-- unless harm of another kind is to be faced. Mimi should have some protector whom all the world would recognise. The only form recognised by convention is marriage!"

Sir Nathaniel smiled in a fatherly way.

"To marry, a husband is required. And that husband should be you."

"Yes, yes."

"And the marriage should be immediate and secret--or, at least, not spoken of outside ourselves. Would the young lady be agreeable to that proceeding?"

"I do not know, sir!"

"Then how are we to proceed?"

"I suppose that we--or one of us--must ask her."

"Is this a sudden idea, Adam, a sudden resolution?"

"A sudden resolution, sir, but not a sudden idea. If she agrees, all is well and good. The sequence is obvious."

"And it is to be kept a secret amongst ourselves?"

"I want no secret, sir, except for Mimi's good. For myself, I should like to shout it from the house-tops! But we must be discreet; untimely knowledge to our enemy might work incalculable harm."

"And how would you suggest, Adam, that we could combine the momentous question with secrecy?"

Adam grew red and moved uneasily.

"Someone must ask her--as soon as possible!"

"And that someone?"

"I thought that you, sir, would be so good!"

"God bless my soul! This is a new kind of duty to take on--at my time of life. Adam, I hope you know that you can count on me to help in any way I can!"

"I have already counted on you, sir, when I ventured to make such a suggestion. I can only ask," he added, "that you will be more than ever kind to me--to us--and look on the painful duty as a voluntary act of grace, prompted by kindness and affection."

"Painful duty!"

"Yes," said Adam boldly. "Painful to you, though to me it would be all joyful."

"It is a strange job for an early morning! Well, we all live and learn. I suppose the sooner I go the better. You had better write a line for me to take with me. For, you see, this is to be a somewhat unusual transaction, and it may be embarrassing to the lady, even to myself. So we ought to have some sort of warrant, something to show that we have been mindful of her feelings. It will not do to take acquiescence for granted--although we act for her good."

"Sir Nathaniel, you are a true friend; I am sure that both Mimi and I shall be grateful to you for all our lives--however long they may be!"

So the two talked it over and agreed as to points to be borne in mind by the ambassador. It was striking ten when Sir Nathaniel left the house, Adam seeing him quietly off.

As the young man followed him with wistful eyes--almost jealous of the privilege which his kind deed was about to bring him--he felt that his own heart was in his friend's breast.

The memory of that morning was like a dream to all those concerned in it. Sir Nathaniel had a confused recollection of detail and sequence, though the main facts stood out in his memory boldly and clearly. Adam Salton's recollection was of an illimitable wait, filled with anxiety, hope, and chagrin, all dominated by a sense of the slow passage of time and accompanied by vague fears. Mimi could not for a long time think at all, or recollect anything, except that Adam loved her and was saving her from a terrible danger. When she had time to think, later on, she wondered when she had any ignorance of the fact that Adam loved her, and that she loved him with all her heart. Everything, every recollection however small, every feeling, seemed to fit into those elemental facts as though they had all been moulded together. The main and crowning recollection was her saying goodbye to Sir Nathaniel, and entrusting to him loving messages, straight from her heart, to Adam Salton, and of his bearing when-- with an impulse which she could not check--she put her lips to his and kissed him. Later, when she was alone and had time to think, it was a passing grief to her that she would have to be silent, for a time, to Lilla on the happy events of that strange mission.

She had, of course, agreed to keep all secret until Adam should give her leave to speak.

The advice and assistance of Sir Nathaniel was a great help to Adam in carrying out his idea of marrying Mimi Watford without publicity. He went with him to London, and, with his influence, the young man obtained the license of the Archbishop of Canterbury for a private marriage. Sir Nathaniel then persuaded old Mr. Salton to allow his nephew to spend a few weeks with him at Doom Tower, and it was here that Mimi became Adam's wife. But that was only the first step in their plans; before going further, however, Adam took his bride off to the Isle of Man. He wished to place a stretch of sea between Mimi and the White Worm, while things matured. On their return, Sir Nathaniel met them and drove them at once to Doom, taking care to avoid any one that he knew on the journey.

Sir Nathaniel had taken care to have the doors and windows shut and locked--all but the door used for their entry. The shutters were up and the blinds down. Moreover, heavy curtains were drawn across the windows. When Adam commented on this, Sir Nathaniel said in a whisper:

"Wait till we are alone, and I'll tell you why this is done; in the meantime not a word or a sign. You will approve when we have had a talk together."

They said no more on the subject till after dinner, when they were ensconced in Sir Nathaniel's study, which was on the top storey. Doom Tower was a lofty structure, situated on an eminence high up in the Peak. The top commanded a wide prospect, ranging from the hills above the Ribble to the near side of the Brow, which marked the northern bound of ancient Mercia. It was of the early Norman period, less than a century younger than Castra Regis. The windows of the study were barred and locked, and heavy dark curtains closed them in. When this was done not a gleam of light from the tower could be seen from outside.

When they were alone, Sir Nathaniel explained that he had taken his old friend, Mr. Salton, into full confidence, and that in future all would work together.

"It is important for you to be extremely careful. In spite of the fact that our marriage was kept secret, as also your temporary absence, both are known."

"How? To whom?"

"How, I know not; but I am beginning to have an idea."

"To her?" asked Adam, in momentary consternation.

Sir Nathaniel shivered perceptibly.

"The White Worm--yes!"

Adam noticed that from now on, his friend never spoke of Lady Arabella otherwise, except when he wished to divert the suspicion of others.

Sir Nathaniel switched off the electric light, and when the room was pitch dark, he came to Adam, took him by the hand, and led him to a seat set in the southern window. Then he softly drew back a piece of the curtain and motioned his companion to look out.

Adam did so, and immediately shrank back as though his eyes had opened on pressing danger. His companion set his mind at rest by saying in a low voice:

"It is all right; you may speak, but speak low. There is no danger here--at present!"

Adam leaned forward, taking care, however, not to press his face against the glass. What he saw would not under ordinary circumstances have caused concern to anybody. With his special knowledge, it was appalling--though the night was now so dark that in reality there was little to be seen.

On the western side of the tower stood a grove of old trees, of forest dimensions. They were not grouped closely, but stood a little apart from each other, producing the effect of a row widely planted. Over the tops of them was seen a green light, something like the danger signal at a railway-crossing. It seemed at first quite still; but presently, when Adam's eye became accustomed to it, he could see that it moved as if trembling. This at once recalled to Adam's mind the light quivering above the well-hole in the darkness of that inner room at Diana's Grove, Oolanga's awful shriek, and the hideous black face, now grown grey with terror, disappearing into the impenetrable gloom of the mysterious orifice. Instinctively he laid his hand on his revolver, and stood up ready to protect his wife. Then, seeing that nothing happened, and that the light and all outside the tower remained the same, he softly pulled the curtain over the window.

Sir Nathaniel switched on the light again, and in its comforting glow they began to talk freely.