The gentleman who was approaching the two girls was a quietly-dressed man of about thirty-two, but he looked somewhat older. He was tall and broad-shouldered. His clean-shaved face was massive in its make, and indicative of power. His expression was grave, and women would have put him down as plain were it not for his eyes, clear thoughtful brown eyes, with a noble look in them that inspired confidence and respect.

Dr. Duncan had acquired a considerable reputation as a surgeon since we last saw him in the Gaiety with Tommy Hudson. He was still working in the same hospital—that in which Mary and Susan were undergoing their training as nurses.

Taking off his hat, he addressed the girls in a pleasant tone. "I am glad to see that you are making the best of this beautiful afternoon. How lovely the foliage of the trees is, Miss Riley; is it not? I don't think I ever remember seeing such fine autumnal effects in the heart of London."

Susan replied in a sentimental voice: "Yes, doctor; but it means hard work for us I fear. This still dank weather makes nature look like a sort of huge death-bed, the vegetation rotting slowly, and the steam of decay hanging over everything. It's just the weather to breed fevers and rheumatisms. The weakly ill-fed poor will inhale the foul breath of the dying air, and rot off like all these pretty hectic leaves you are admiring so much."

The false voice in which she said this rather jarred on Dr. Duncan. He looked at her curiously, and said:

"Yes! but it is better for them than the cold winds and the snow and the frost after all, Miss Riley. The maladies and deaths they cause are out of the reach of us doctors, though the remedies are simple enough, God knows. Coals and bread, that is all that is wanted to stop nine-tenths of the illness of what is called a good old-fashioned winter."

Susan gave the doctor a soft look out of her voluptuous wicked eyes, and exclaimed in a sort of mellow cooing voice, which she knew how to put on when she wanted to fascinate: and it was well calculated to effect this object:

"Ah, doctor! they say that you give away a great deal of that sort of medicine among the poor of this district sometimes. How gratefully they speak of you! You are idolized in the lowest slums. They would die for you. It must be delicious to be loved by all as you are," and she threw out a sigh and another bewitching glance.

But the flattery was a little too thickly laid on for a man of this stamp, though he liked flattery well enough, as all men do, bad or good.

He turned to Mary and said, "Miss King, I have been concerned to see how pale and ill you have been looking of late. I am afraid the hard work is upsetting you. You should take a holiday. Why don't you run down to the sea-side for a week?"

Mary coloured slightly, and said, coldly: "Indeed, I feel very well, thank you, Dr. Duncan. I generally am rather pale, but I think I am as strong as anyone can be."

Susan felt rather annoyed at the manner with which her remarks had been received. She wanted to monopolize the doctor's conversation. She had been setting her cap at him for some time, for what purpose it is difficult to say, unless it were out of mere malice and vanity; for in her heart she disliked this cold man who would not fall into a violent infatuation about her, as most others would have done after a quarter of the love-making she had thrown away on him.

And now she remembered her time was up. She must return to the hospital, and perhaps the doctor would walk part of the way home with Mary. It was most provoking; for she felt that Mary's charms were as great as her own, greater perhaps, she suspected, when a wise man was concerned, though that silly child did not know how to employ them.

"Oh, dear!" she exclaimed, "I wish I could stay a little longer in this pretty place, and have a pleasant chat with you two, but it is time for me to go home."

"I am going home now, Susan," said Mary, "and I will walk as far as the hospital with you. It is on my way."

"And on mine too," said the doctor. "If you allow me I will accompany you."

Mary made no reply.

"Oh! how nice," gushed Susan. "It is so lonely to walk down all those dingy streets by oneself. It is a treat to have somebody with one, especially—" and the cunning beauty checked herself, and pretended to be embarrassed.

They talked on indifferent matters till they reached the gates of the hospital, through which Susan passed after affectionately kissing the younger woman, and a parting, "Good-bye, Mary, I'll see you to-morrow morning; good-bye, doctor."

"I am going to Praed Street," said the doctor. "That is in your direction I think. I am going to walk. It will do you good to walk too, Miss King, if you are not tired. Shall we go together? It will be a very great pleasure for me."

"Thank you, Dr. Duncan, I shall be very glad. I don't feel inclined to go in a stuffy omnibus on such a fine afternoon."

So they went together through the now gaslit streets, that were filled with that haze of the still November afternoon, which the true Londoner loves for the soft melancholy of it. It is all very well for us to abuse our London fogs; but there are fogs and fogs, and who would exchange that dreamy poetic indistinctness of effect, which Turner so well knew how to express on canvas, for all the hard clear outline of your Southern cities.

I remember once, in Buenos Ayres, seeing tears come to the eyes of an old Bohemian of Fleet Street, who had for years been dwelling in that city of pellucid atmosphere, when one winter evening a genuine English mistiness made its appearance for a while, reminding that home-sick exile of his dear dingy city of the far Northern island.

This was by no means the first time that the doctor had walked home with Mary. A mutual liking had for some time existed between them; but so far the keenest observer could not have detected, in a word or look of either, any signs of serious affection, if such existed. They were not a demonstrative couple, and did not carry their hearts on their sleeves as Sister Susan seemed to do.

The doctor would speak to her in a calm respectful way, paying only those attentions a well-bred man always pays to a young woman.

She, very much on her guard when with him, affected a manner that would have repulsed many less earnest admirers. She would be cold, curt almost to rudeness, and went so far as to assume, at times, a flippant cynicism, which she was far from feeling.

But the soft languor of this November afternoon seemed to have entered into the girl's soul; and during this particular walk her power of putting on such defensive affectations failed her for once.

Said the doctor: "What a strange girl that Miss Riley is; I cannot make her out at all."

"She is a very good nurse," replied Mary.

"Excellent; but she is different from all I have ever seen. She shows none of the nervousness, the more or less concealed repugnance, all other girls exhibit at the commencement of this unpleasant training."

"She is kind to the patients."

"Oh, yes! She in a way is the kindest of you all. She is never awkward. She sets to work in such a business-like way, and is so quick and deft. She is so free from nervousness that she inflicts a minimum of pain on a patient. She would make a splendid surgeon. But she seems to have no feeling for them, or, at any rate, conceals it as no novice ever did before. I have seen her assisting at a horrible surgical case, and she looked as calm, even absent-minded, over it, as if it had been a case of gardening, trimming and pruning plants, and not poor human flesh."

"I wish I was like her: I am very stupid and nervous sometimes."

"And yet I think I would rather be nursed by you, Miss King."

"I don't think it is very charitable of us to be criticising poor Miss Riley behind her back," said Mary, wishing to turn the conversation.

"Of us! Of me you mean. I am the only culprit. You have been generously taking up the cudgels in her defence. But we will change the subject. I have heard nothing of your aunt for some time. May I ask how she is?"

"My aunt! Oh, Mrs. King! She is very well indeed, thank you, Dr. Duncan; but I did not know you were even aware of her existence."

"I only heard, by accident, the other day, that she was your aunt, and that you lived with her; but I have known of her existence for years."

"Indeed!" exclaimed Mary.

"Oh, yes! She used to speak and lecture on woman's rights, on the abolition of the House of Lords, and such like questions. I heard her several times: very eloquent she was too. I was rather a Radical myself then, but I have changed my views since.... I trust you do not follow your aunt in all her opinions, Miss King?" and he looked rather anxiously at her.

"I think I do, Dr. Duncan."

There was a silence for a while. The man was evidently troubled, and was carefully pondering his next remark. Mary regarded him furtively, wondering what was coming.

"Some of your aunt's views are rather startling," he said. He was thinking of one of her speeches he had heard, in which she had upheld the unsavoury teachings of Mr. Bradlaugh, and had declared her favourite opinions as to the abominable nature of religion and morality.

"Startling! yes, I suppose they are startling—truth often is so," she replied.

"Is it truth?"

"Is what truth?" and she turned and looked him full in the face.

Finding himself driven into a corner, he spoke out boldly. "Miss King, I hope you will forgive me when I tell you that I feel a deep interest in you. I hope you will look on me as your friend, and that we shall know each other better some day. Do not think I am impertinent if I explain what I meant."

"I do not think so, Dr. Duncan."

"Well, I know what your aunt's opinions on certain matters—religion for instance—are, and I should be very sorry to think that you entertained the same."

"Oh! are they false opinions?"

"I think so; but that is hardly the question. Some false opinions are at any rate harmless, but these I speak of are certainly bad in their effects, whether they be true or false."

"Do you then believe that to know the truth can be bad?" she asked in a sarcastic tone.

"I don't say that; but don't you think that when a theory is put before you, you should be much more careful than usual in your examination of it, should require much more—indeed, absolute proof—before you accept it, if it is a theory, the belief in which cannot fail to have bad consequences?"

"A theory should stand on its own merits. It is no argument against an opinion to say that it is an unhappy one."

"Certainly not; but, surely, unless we are quite convinced that such a theory is correct—a difficult matter, as a rule—we should be very rash in not only accepting it, but in acting up to it. Take a parallel case, Miss King. In a court of law a far stronger and more indisputable chain of evidence is required to bring about an adverse verdict in the case of a prisoner charged with a capital crime, than in the case of one who is accused of an injury to a fellow that only makes him liable to a civil action. It is in that spirit, I think, we should try opinions on which the whole happiness of mankind depends. Before we condemn religion, and put away the system of morality which follows it, we should surely ask for more convincing evidence against them, than if it were merely a question of the truth or falsehood of some opinion which cannot influence mankind much either way for good or evil."

"Don't you call that an 'argumentum ad hominem?'" Mary said.

"I see I have a logician to deal with in you, Miss King. Mind, I do not wish to discuss religious truths with you. I am not a clergyman. I am merely throwing out suggestions as to the state of mind with which, I believe, one ought to approach speculations of this nature."

"Are you a religious man, Dr. Duncan?—but it is very rude of me to ask such a question."

"I am sorry to say I am not. My work is my religion at present, and fills all my thought."

"Why should not my work be my religion?"

"If it was it would be very well. To alleviate human misery is to act religion. Though I am far from being a religious man, and rarely go inside a church; though I may be a bad man, I do not question the fundamental laws of morality, on which I believe the whole happiness and loveliness of the human race depend. Now, your aunt does this; and though one may—mind, may—get on, and be virtuous, and good, and lovable, without being what people call religious, I doubt whether one can be so if one is constantly trying to prove to oneself that a priori religious and moral systems are untrue—if one comes to think that no action is per se bad and to be avoided. We must have a dogmatic morality, Miss King. I don't say that we can altogether act up to it, but we must believe in it. The evil-living man, who still admires and respects virtue, is in a happier way, I think, than a man, good in action, who yet has no belief in good. I know Mrs. King is one who has carried Utilitarian ethics to their extreme conclusions. This is a dangerous thing for us poor mortals to attempt. Misery is the result. Utilitarianism may do for angels—it won't do for us."

There were tears in Mary's eyes as he concluded. She had been too long fed on unwholesome doctrine to be in any way influenced by his arguments. He had merely told her what she already knew too well, that such a belief as she professed—that truth—was an apple of Sodom, full of bitterness and sorrow; but, somehow, his kind words brought vividly before her the utterness of her desolation, and she said in mournful tones, "Oh, how wicked you would think me if you knew all my thoughts; how you would loathe me!"

"Pray, don't say such a thing, Miss King," he exclaimed. "Whatever your opinions and doubts may be, you are not wicked. Do you know, I have often watched you in the hospital. I have taken great interest in you. I saw how sad and thoughtful you were, and I saw how kind you were to the sick—how patient, how sympathetic. I observed how you felt with their suffering, not in mere physical revolt at witnessing pain, but with a true woman's pity. No! I know you are not wicked."

He spoke earnestly, with a deep feeling, the meaning of which could hardly be mistaken.

Mary answered not a word. She was overawed by this man. She felt as if she could have sunk into the ground with her sense of shame and degradation. "What, this good man believes that I am good," she thought. "He has faith in me—affection for me! He loves me for my kindness to the sick—me, that am training to be a murderess—me, a baby-killer! Oh, the horror of the thing—the despair of my position!" She realized bitterly how deep, how irreconcilable must be her estrangement from her race. "She must never know love—she must steel her heart—crush her sympathies, and, oh! she must never again trust herself to talk in confidence with her fellows, especially with this doctor."

She could not speak with that choking sensation in her throat, so she walked on in silence.

Her companion looked at her and perceived the tears glistening in her downcast eyes. The doctor had, of late, found himself constantly thinking tenderly of this lonely, sad-looking girl, whose only companion was the frivolous Susan. He had, to a certain extent, guessed the cause of her sorrow, living as she did with the half-insane atheist and revolutionist he knew Mrs. King to be. He felt a great pity for the beautiful unprotected creature, in whom he saw such sweet possibilities of love and all the graces and good qualities of woman. The love that was coming to him was deep and strong and fierce as was his nature, and the girl was beginning to divine this.

No wonder that she was filled with dread when she knew that she had inspired such a feeling in such a man; for there lay that terrible secret between them, a secret whose nature he had so little suspected, when she warned him that he would loathe her, did he know it. She found that she was on the edge of a precipice, and felt a sick dizziness to see it, but also a painful fascination.

They walked on together through the dreamy November haze—both feeling as in a dream—without speaking, but each in some strange manner vaguely conscious of the spirit of the other's thought, of a close sympathy that was fast drawing them together. It was as if their hearts beat, their souls sung, in unison, to some awful music from another sphere. The streets and the people were no longer with them.

So it was, that when at last he spoke, the words were expected by her. She seemed to have felt their meaning before they came. They had been led up to by the unspoken emotions of either.

"Oh, Miss King, if you could only confide in me, and make me your friend! I would die, to be able to drive away that cloud from your mind, if I could only see you happy and smiling.... All that beautiful youth of yours, with its sweet possibilities, being destroyed by these dark phantoms! Oh, Mary, for God's sake, trust in me! Have you guessed how I love you? You must have done so. You fill all my thoughts. You know that you are everything in the world to me.... Oh, my sweet! my sweet! that I could make you throw yourself on my love. I believe I would make you happy. I would understand you, Mary, and we would make all your sadness go. We would go right away from the streets for a time, and walk through the green fields hand in hand like children again. In the bright, pure country we should drive all these phantoms right away; our human love would drive them right away. Mary! Mary!—" and he stopped and seized her two hands in his, carried away by his emotion.

They were standing by the railings of the garden of a deserted square, and the rays of a lamp fell full on her pale face.

He had raised an image of wonderful joys to her mind—but, oh! so impossible—so impossible!

She trembled in his grasp. She dared not raise her eyes to meet his.

"Mary! O Mary! can it be true? Do you care for me; do you love me a little?"

She could not preserve that outward calm any longer, with all that storm raging within her. She was stifling with it, and for an answer burst into hysterical sobs.

"Oh! my dear! my dear!" He folded her in his arms, and his passionate kisses were on her eyes and on her mouth.

Then, with a strength that surprised him, she suddenly thrust him off, and retreating a few yards back, stared at him with eyes dilated with horror and anguish.

"Oh! Dr. Duncan!" she cried, with a voice full of such tragedy that the strong man felt his veins tingle with terror. "Oh! go away! go away, and leave me.... You do not know what you are saying.... You are mad. Never speak to me again. Forget me, if you do not wish to be more miserable than ever man was before. You don't know what I am—what I must be. If you married me, you would go mad with what you discovered. You would blow your brains out, and mine too.... I am not exaggerating. I am talking sober truth. I mean this.... Yes, more.... Think of all the greatest criminals you have ever heard of. Think of the most hideous, unspeakable crimes ever invented by man, and then look on me as guilty of them all—yes, all of them, and worse. I warn you—remember, I have warned you."

The intense earnestness of her look—of her speech—terrified him. "What could she mean? Was she mad?" And he felt sick and dizzy with the pain of this thought.

"Now, Dr. Duncan, not another word. I won't bring you any further out of your way. Good-night." And she walked rapidly away.

He stood where he was, supporting himself by the railing—for a moment half-dazed at the shock he had received. Then there came a curious reaction to him after the first effects of her wild words. He was seized by a sort of frenzy—by the strongest of all the passions in its very greatest strength: love—love that is insane, and thinks of nothing—reckless of crime and consequence—the strong man's love that can make of him a fiend or an angel.

His blood tingled through his veins like fire. "Mary," he thought to himself, "Mary, you must be mine. Even if you are mad, I will still have you. I do not care what you are. I would be mad too, rather than lose you. Were you a thousand times worse than you say—if you have committed every crime—it can make no difference now to me. If you were a devil, I should have to become devil too, to please you. It must be love between us—love for good or bad. If it cannot be of heaven, it must be of hell; but love it must—shall be...." And the usually self-possessed man hurried through the streets with his brain on fire, his hands clenched, and his eyes glaring, so that people he passed got to one side or other of him in fear to let him go by, for his face was as that of a madman.

The devil had got hold of him for the time; and after the fit was over, he shuddered when he remembered how wild and wicked his fancies had been—how, in a moment, it had seemed as if all the good of years of careful training had run out of him, and left him a fiend without conscience or fear, capable of any deed, if by it he could but compass his desires.

And so it is with all of us at times. The passionate temptations of a man reveal to him, in flashes, what horrible depths of possible sin lurk in his nature—hidden unsuspected, awaiting their opportunity.

But he had clasped that slight, girlish form in his arms—he had kissed that unkissed mouth, and drawn madness from it—he was the slave of his passion for better or for worse.

Even when he thought more calmly over the whole matter on the following day, he still knew that his love for the girl was altogether his master. He still determined to press his suit.

Even were she really bad, he must risk all, and make her his. But he knew that she was not really bad in heart, though she might have been in action. He would gain her confidence, share with her her repentance for her sin, take on himself her burden. Even had she been the most abandoned of creatures, he would take her to his arms now. Go back he could not—would not.

And yet, of all men this was the one whom none would have suspected capable of making a rash marriage. Ah! how little we know how we ourselves would behave when the moment comes! We are all of us mad and weak then—yes, every one of us.