Rapidly turning into the Fifth Avenue from one of the cross streets above the old reservoir, at quarter past eleven o'clock on the night of November 6, 1879, I ran plump into an individual coming the other way.

It was very dark on this corner. I could see nothing of the person with whom I had the honor to be in collision. Nevertheless, the quick habit of a mind accustomed to induction had furnished me with several well-defined facts regarding him before I fairly recovered from the shock of the encounter.

These were some of the facts: He was a heavier man than myself, and stiffer in the legs; but he lacked precisely three inches and a half of my stature. He wore a silk hat, a cape or cloak of heavy woolen material, and rubber overshoes or arctics. He was about thirty-five years old, born in America, educated at a German university, either Heidelberg or Freiburg, naturally of hasty temper, but considerate and courteous, in his demeanor to others. He was not entirely at peace with society: there was something in his life or in his present errand which he desired to conceal.

How did I know all this when I had not seen the stranger, and when only a single monosyllable had escaped his lips? Well, I knew that he was stouter than myself, and firmer on his foot, because it was I, not he, who recoiled. I knew that I was just three inches and a half taller than he, for the tip of my nose was still tingling from its contact with the stiff, sharp brim of his hat. My hand, involuntarily raised, had come under the edge of his cape. He wore rubber shoes, for I had not heard a footfall. To an observant ear; the indications of age are as plain in the tones of the voice as to the eye in the lines of the countenance. In the first moment of exasperation of my maladroitness, he had muttered “Ox!” a term that would occur to nobody except a German at such a time. The pronunciation of the guttural, however, told me that the speaker was an American German, not a German American, and that his German education had been derived south of the river Main. Moreover, the tone of the gentleman and scholar was manifest even in the utterance of wrath. That the gentleman was in no particular hurry, but for some reason anxious to remain unknown; was a conclusion drawn from the fact that, after listening in silence to my polite apology, he stooped to recover and restore to me my umbrella, and then passed on as noiselessly as he had approached.

I make it a point to verify my conclusions when possible. So I turned back into the cross street and followed the stranger toward a lamp part way down the block. Certainly, I was not more than five seconds behind him. There was no other road that he could have taken. No house door had opened and closed along the way. And yet, when we came into the light, the form that ought to have been directly in front of me did not appear. Neither man nor man’s shadow was visible.

Hurrying on as fast as I could walk to the next gaslight, I paused under the lamp and listened. The street was apparently deserted. The rays from the yellow flame reached only a little way into the darkness. The steps and doorway, however, of the brownstone house facing the street lamp were sufficiently illuminated. The gilt figures above the door were distinct. I recognized the house: the number was a familiar one. While I stood under the gaslight, waiting, I heard a slight noise on these steps, and the click of a key in a lock. The vestibule door of the house was slowly opened, and then closed with a slam that echoed across the street. Almost immediately followed the sound of the opening and shutting of the inner door. Nobody had come out. As far as my eyes could be trusted to report an event hardly ten feet away and in broad light, nobody had gone in.

With a notion that here was scanty material for an exact application of the inductive process, I stood a long time wildly guessing at the philosophy of the strange occurrence. I felt that vague sense of the unexplainable which amounts almost to dread. It was a relief to hear steps on the sidewalk opposite, and turning, to see a policeman swinging his long black club and watching me.


This house of chocolate brown, whose front door opened and shut at midnight without indications of human agency, was, as I have said, well known to me. I had left it not more than ten minutes earlier, after spending the evening with my friend Bliss and his daughter Pandora. The house was of the sort in which each story constitutes a domicile complete in itself. The second floor, or flat, had been inhabited by Bliss since his return from abroad; that is to say, for a twelvemonth. I held Bliss in esteem for for his excellent qualities of heart, while his deplorably illogical and unscientific mind commanded my profound pity. I adored Pandora.

Be good enough to understand that my admiration for Pandora Bliss was hopeless, and not only hopeless, but resigned to its hopelessness. In our circle of acquaintance there was a tacit covenant that the young lady’s peculiar position as a flirt wedded to a memory should be at all times respected. We adored Pandora mildly, not passionately–just enough to feed her coquetry without excoriating the seared surface of her widowed heart. On her part, Pandora conducted herself with signal propriety. She did not sigh too obtrusively when she flirted: and she always kept her flirtations so well in hand that she could cut them short whenever the fond, sad recollections came.

It was considered proper for us to tell Pandora that she owed it to her youth and beauty to put aside the dead past like a closed book, and to urge her respectfully to come forth into the living present. It was not considered proper to press the subject after she had once replied that this was forever impossible.

The particulars of the tragic episode in Miss Pandora’s European experience were not accurately known to us. It was understood, in a vague way, that she had loved while abroad, and trifled with her lover: that he had disappeared, leaving her in ignorance of his fate and in perpetual remorse for her capricious behavior. From Bliss I had gathered a few, sporadic facts, not coherent enough to form a history of the case. There was no reason to believe that Pandora’s lover had committed suicide. His name was Flack. He was a scientific man. In Bliss’s opinion he was a fool. In Bliss’s opinion Pandora was a fool to pine on his account. In Bliss’s opinion all scientific men were more or less fools.


That year I ate Thanksgiving dinner with the Blisses. In the evening I sought to astonish the company by reciting the mysterious events on the night of my collision with the stranger. The story failed to produce the expected sensation. Two or three odious people exchanged glances. Pandora, who was unusually pensive, listened with seeming indifference. Her father, in his stupid inability to grasp anything outside the commonplace, laughed outright, and even went so far as to question my trustworthiness as an observer of phenomena.

Somewhat nettled, and perhaps a little shaken in my own faith in the marvel, I made an excuse to withdraw early. Pandora accompanied me to the threshold. “Your story,” said she, “interested me strangely. I, too, could report occurrences in and about this house which would surprise you. I believe I am not wholly in the dark. The sorrowful past casts a glimmer of light–but let us not be hasty. For my sake probe the matter to the bottom.”

The young woman sighed as she bade me good night. I thought I heard a second sigh, in a deeper tone than hers, and too distinct to be a reverberation.

I began to go downstairs. Before I had descended half a dozen steps I felt a man’s hand laid rather heavily upon my shoulder from behind. My first idea was that Bliss had followed me into the hall to apologize for his rudeness. I turned around to meet his friendly overture. Nobody was in sight.

Again the hand touched my arm. I shuddered in spite of my philosophy.

This time the hand gently pulled at my coat sleeve, as if to invite me upstairs. I ascended a step or two, and the pressure on my arm was relaxed. I paused, and the silent invitation was repeated with an urgency that left no doubt as to what was wanted.

We mounted the stairs together, the presence leading the way, I following. What an extraordinary journey it was! The halls were bright with gaslight. By the testimony of my eyes there was no one but myself upon the stairway. Closing my eyes, the illusion, if illusion it could be called, was perfect. I could hear the creaking of the stairs ahead of me, the soft but distinctly audible footfalls synchronous with my own, even the regular breathing of my companion and guide. Extending my arm, I could touch and finger the skirt of his garment–a heavy woolen cloak lined with silk.

Suddenly I opened my eyes. They told me again that I was absolutely alone.

This problem then presented itself to mind: How to determine whether vision was playing me false, while the senses of hearing and feeling correctly informed me, or whether my ears and touch lied, while my eyes reported the truth. Who shall be arbiter when the senses contradict each other? The reasoning faculty? Reason was inclined to recognize the presence of an intelligent being, whose existence was flatly denied by the most trusted of the senses.

We reached the topmost floor of the house. The door leading out of the public hall opened for me, apparently of its own accord. A curtain within seemed to draw itself aside, and hold itself aside long enough to give me ingress to an apartment wherein every appointment spoke of good taste and scholarly habits. A wood fire was burning in the chimney place. The walls were covered with books and pictures. The lounging chairs were capacious and inviting. There was nothing in the room uncanny, nothing weird, nothing different from the furniture of everyday flesh and blood existence.

By this time I had cleared my mind of the last lingering suspicion of the supernatural. These phenomena were perhaps not inexplicable; all that I lacked was the key. The behavior of my unseen host argued his amicable disposition. I was able to watch with perfect calmness a series of manifestations of independent energy on the part of inanimate objects.

In the first place, a great Turkish easy chair wheeled itself out of a corner of the room and approached the hearth. Then a square-backed Queen Anne chair started from another corner, advancing until it was planted directly opposite the first. A little tripod table lifted itself a few inches above the floor and took a position between the two chairs. A thick octavo volume backed out of its place on the shelf and sailed tranquilly through the air at the height of three or four feet, landing neatly on top of the table. A finely painted porcelain pipe left a hook on the wall and joined the volume. A tobacco box jumped from the mantlepiece. The door of a cabinet swung open, and a decanter and wineglass made the journey in company, arriving simultaneously at the same destination. Everything in the room seemed instinct with the spirit of hospitality.

I seated myself in the easy chair, filled the wineglass, lighted the pipe, and examined the volume. It was the Handbuch der Gewebelehre of Bussius of Vienna. When I had replaced the book upon the table, it deliberately opened itself at the four hundred and forty-third page.

“You are not nervous?” demanded a voice, not four feet from my tympanum.


This voice had a familiar sound. I recognized it as the voice that I heard in the street on the night of November 6, when it called me an ox.

“No,” I said. “I am not nervous. I am a man of science, accustomed to regard all phenomena as explainable by natural laws, provided we can discover the laws. No, I am not frightened.”

“So much the better. You are a man of science, like myself”–here the voice groaned–“a man of nerve, and a friend of Pandora’s.”

“Pardon me,” I interposed. “Since a lady’s name is introduced it would be well to know with whom or with what I am speaking.”

“That is precisely what I desire to communicate,” replied the voice, “before I ask you to render me a great service. My name is or was Stephen Flack. I am or have been a citizen of the United States. My exact status at present is as great a mystery to myself as it can possibly be to you. But I am, or was, an honest man and a gentleman, and I offer you my hand.”

I saw no hand. I reached forth my own, however, and it met the pressure of warm, living fingers.

“Now,” resumed the voice, after this silent pact of friendship, “be good enough to read the passage at which I have opened the book upon the table.”

Here is a rough translation of what I read in German:

As the color of the organic tissues constituting the body depends upon the presence of certain proximate principles of the third class, all containing iron as one of the ultimate elements, it follows that the hue may vary according to well-defined chemico-physiological changes. An excess of hematin in the blood globules gives a ruddier tinge to every tissue. The melanin that colors the choroid of the eye, the iris, the hair, may be increased or diminished according to laws recently formulated by Schardt of Basel. In the epidermis the excess of melanin makes the Negro, the deficient supply the albino. The hematin and the melanin, together with the greenish-yellow biliverdine and the reddish-yellow urokacine, are the pigments which impart color character to tissues otherwise transparent, or nearly so. I deplore my inability to record the result of some highly interesting histological experiments conducted by that indefatigable investigator Fröliker in achieving success in the way of separating pink discoloration of the human body by chemical means.

“For five years,” continued my unseen companion when I had finished reading, “I was Fröliker’s student and laboratory assistant at Freiburg. Bussius only half guessed at the importance of our experiments. We reached results which were so astounding that public policy required they should not be published, even to the scientific world. Fröliker died a year ago last August.

"I had faith in the genius of this great thinker and admirable man. If he had rewarded my unquestioning loyalty with full confidence, I should not now be a miserable wretch. But his natural reserve, and the jealousy with which all savants guard their unverified results, kept me ignorant of the essential formulas governing our experiments. As his disciple I was familiar with the laboratory details of the work; the master alone possessed the radical secret. The consequence is that I have been led into a misfortune more appalling than has been the lot of any human being since the primal curse fell upon Cain.

"Our efforts were at first directed to the enlargement and variation of the quantity of pigmentary matter in the system. By increasing the proportion of melanin, for instance, conveyed in food to the blood, we were able to make a fair man dark, a dark man black as an African. There was scarcely a hue we could not impart to the skin by modifying and varying our combinations. The experiments were usually tried on me. At different times I have been copper-colored, violet blue, crimson, and chrome yellow. For one triumphant week I exhibited in my person all the colors of the rainbow. There still remains a witness to the interesting character of our work during this period.”

The voice paused, and in a few seconds a hand bell upon the mantel was sounded. Presently an old man with a close-fitting skullcap shuffled into the room.

“Käspar,” said the voice, in German, “show the gentleman your hair.”

Without manifesting any surprise, and as if perfectly accustomed to receive commands addressed to him out of vacancy, the old domestic bowed and removed his cap. The scanty locks thus discovered were of a lustrous emerald green. I expressed my astonishment.

“The gentleman finds your hair very beautiful,” said the voice, again in German. “That is all, Käspar.”

Replacing his cap, the domestic withdrew, with a look of gratified vanity on his face.

“Old Käspar was Fröliker’s servant, and is now mine. He was the subject of one of our first applications of the process. The worthy man was so pleased with the result that he would never permit us to restore his hair to its original red. He is a faithful soul, and my only intermediary and representative in the visible world.

"Now,” continued Flack, “to the story of my undoing. The great histologist with whom it was my privilege to be associated, next turned his attention to another and still more interesting branch of the investigation. Hitherto he had sought merely to increase or to modify the pigments in the tissues. He now began a series of experiments as to the possibility of eliminating those pigments altogether from the system by absorption, exudation, and the use of the chlorides and other chemical agents acting on organic matter. He was only too successful!

"Again I was the subject of experiments which Fröliker supervised, imparting to me only so much of the secret of this process as was unavoidable. For weeks at a time I remained in his private laboratory, seeing no one and seen by no one excepting the professor and the trustworthy Käspar. Herr Friiliker proceeded with caution, closely watching the effect of each new test, and advancing by degrees. He never went so far in one experiment that he was unable to withdraw at discretion. He always kept open an easy road for retreat. For that reason I felt myself perfectly safe in his hands and submitted to whatever he required.

"Under the action of the etiolating drugs which the professor administered in connection with powerful detergents, I became at first pale, white, colorless as an albino, but without suffering in general health. My hair and beard looked like spun glass and my skin like marble. The professor was satisfied with his results, and went no further at this time. He restored to me my normal color.

"In the next experiment, and in those succeeding, he allowed his chemical agents to take firmer hold upon the tissues of my body. I became not only white, like a bleached man, but slightly translucent, like a porcelain figure. Then again he paused for a while, giving me back my color and allowing me to go forth into the world. Two months later I was more than translucent. You have seen floating those sea radiates, the medusa or jellyfish, their outlines almost invisible to the eye. Well, I became in the air like a jellyfish in the water. Almost perfectly transparent, it was only by close inspection that old Käspar could discover my whereabouts in the room when he came to bring me food. It was Käspar who ministered to my wants at times when I was cloistered.”

“But your clothing?” I inquired, interrupting Flack’s narrative. “That must have stood out in strong contrast with the dim aspect of your body.”

“Ah, no,” said Flack. “The spectacle of an apparently empty suit of clothes moving about the laboratory was too grotesque even for the grave professor. For the protection of his gravity he was obliged to devise a way to apply his process to dead organic matter, such as the wool of my cloak, the cotton of my shirts, and the leather of my shoes. Thus I came to be equipped with the outfit which still serves me.

"It was at this stage of our progress, when we had almost attained perfect transparency, and therefore complete invisibility, that I met Pandora Bliss.

"A year ago last July, in one of the intervals of our experimenting, and at a time when I presented my natural appearance, I went into the Schwarzwald to recuperate. I first saw and admired Pandora at the little village of St. Blasien. They had come from the Falls of the Rhine, and were traveling north; I turned around and traveled north. At the Stern Inn I loved Pandora; at the summit of the Feldberg I madly worshiped her. In the Höllenpass I was ready to sacrifice my life for a gracious word from her lips. On Hornisgrinde I besought her permission to throw myself from the top of the mountain into the gloomy waters of the Mummelsee in order to prove my devotion. You know Pandora. Since you know her, there is no need to apologize for the rapid growth of my infatuation. She flirted with me, laughed with me, laughed at me, drove with me, walked with me through byways in the green woods, climbed with me up aeclivities so steep that climbing together was one delicious, prolonged embrace; talked science with me, and sentiment; listened to my hopes and enthusiasm, snubbed me, froze me, maddened me–all at her sweet will, and all while her matter-of- fact papa dozed in the coffee rooms of the inns over the financial columns of the latest New York newspapers. But whether she loved me I know not to this day.

"When Pandora’s father learned what my pursuits were, and what my prospects, he brought our little idyl to an abrupt termination. I think he classed me somewhere between the professional jugglers and the quack doctors. In vain I explained to him that I should be famous and probably rich. ‘When you are famous and rich,’ he remarked with a grin, 'I shall be pleased to see you at my office in Broad street’ He carried Pandora off to Paris, and I returned to Freiburg.

"A few weeks later, one bright afternoon in August, I stood in Fröliker’s laboratory unseen by four persons who were almost within the radius of my arm’s length. Käspar was behind me, washing some test tubes. Fröliker, with a proud smile upon his face, was gazing intently at the place where he knew I ought to be. Two brother professors, summoned on some pretext, were unconsciously almost jostling me with their elbows as they discussed I know not what trivial question. They could have heard my heart beat. 'By the way, Herr Professor,’ one asked as he was about to depart, 'has your assistant, Herr Flack, returned from his vacation?’ This test was perfect.

"As soon as we were alone, Professor Fröliker grasped my invisible hand, as you have grasped it tonight. He was in high spirits.

”'My dear fellow,’ he said, 'tomorrow crowns our work. You shall appear–or rather not appear–before the assembled faculty of the university. I have telegraphed invitations to Heidelberg, to Bonn, to Berlin. Schrotter, Haeckel, Steinmetz, Lavallo, will be here. Our triumph will be in presence of the most eminent physicists of the age. I shall then disclose those secrets of our process which I have hitherto withheld even from you, my colaborer and trusted friend. But you shall share the glory. What is this I hear about the forest bird that has flown? My boy, you shall be restocked with pigment and go to Paris to seek her with fame in your hands and the blessings of science on your head.’

“The next morning, the nineteenth of August, before I had arisen from my cot bed, Käspar hastily entered the laboratory.

”'Herr Flack! Herr Flack!’ he gasped, 'the Herr Doctor Professor is dead of apoplexy.’“


The narrative had come to an end. I sat a long time thinking. What could I do? What could I say? In what shape could I offer consolation to this unhappy man?

Flack, the invisible, was sobbing bitterly.

He was the first to speak. "It is hard, hard, hard! For no crime in the eyes of man, for no sin in the sight of God, I have been condemned to a fate ten thousand times worse than hell. I must walk the earth, a man, living, seeing, loving, like other men, while between me and all that makes life worth having there is a barrier fixed forever. Even ghosts have shapes. My life is living death; my existence oblivion. No friend can look me in the face. Were I to clasp to my breast the woman I love, it would only be to inspire terror inexpressible. I see her almost every day. I brush against her skirts as I pass her on the stairs. Did she love me? Does she love me? Would not that knowledge make the curse still more cruel? Yet it was to learn the truth that I brought you here.”

Then I made the greatest mistake of my life.

“Cheer up!” I said. “Pandora has always loved you.”

By the sudden overturning of the table I knew with what vehemence Flack sprang to his feet. His two hands had my shoulders in a fierce grip.

“Yes,” I continued; “Pandora has been faithful to your memory. There is no reason to despair. The secret of Fröliker’s process died with him, but why should it not be rediscovered by experiment and induction ab initio, with the aid which you can render? Have courage and hope. She loves you. In five minutes you shall hear it from her own lips.”

No wail of pain that I ever heard was half so pathetic as his wild cry of joy.

I hurried downstairs and summoned Miss Bliss into the hall. In a few words I explained the situation. To my surprise, she neither fainted nor went into hysterics. “Certainly, I will accompany you,” she said, with a smile which I could not then interpret.

She followed me into Flack’s room, calmly scrutinizing every corner of the apartment, with the set smile still upon her face. Had she been entering a ballroom she could not have shown greater self-possession. She manifested no astonishment, no terror, when her hand was seized by invisible hands and covered with kisses from invisible lips. She listened with composure to the torrent of loving and caressing words which my unfortunate friend poured into her ears.

Perplexed and uneasy, I watched the strange scene.

Presently Miss Bliss withdrew her hand.

“Really, Mr. Flack,” she said with a light laugh, “you are sufficiently demonstrative. Did you acquire the habit on the Continent?”

“Pandora!” I heard him say, “I do not understand.”

“Perhaps,” she calmly went on, “you regard it as one of the privileges of your invisibility. Let me congratulate you on the success of your experiment. What a clever man your professor–what is his name?–must be. You can make a fortune by exhibiting yourself.”

Was this the woman who for months had paraded her inconsolable sorrow for the loss of this very man? I was stupefied. Who shall undertake to analyze the motives of a coquette? What science is profound enough to unravel her unconscionable whims?

“Pandora!” he exclaimed again, in a bewildered voice. “What does it mean? Why do you receive me in this manner? Is that all you have to say to me?”

“I believe that is all,” she coolly replied, moving toward the door. “You are a gentleman, and I need not ask you to spare me any further annoyance.”

“Your heart is quartz,” I whispered, as she passed me in going out. “You are unworthy of him.”

Flack’s despairing cry brought Käspar into the room. With the instinct acquired by long and faithful service, the old man went straight to the place where his master was. I saw him clutch at the air, as if struggling with and seeking to detain the invisible man. He was flung violently aside. He recovered himself and stood an instant listening, his neck distended, his face pale. Then he rushed out of the door and down the stairs. I followed him.

The street door of the house was open. On the sidewalk Käspar hesitated a few seconds. It was toward the west that he finally turned, running down the street with such speed that I had the utmost difficulty to keep at his side.

It was near midnight. We crossed avenue after avenue. An inarticulate murmur of satisfaction escaped old Käspar’s lips. A little way ahead of us we saw a man, standing at one of the avenue corners, suddenly thrown to the ground. We sped on, never relaxing our pace. I now heard rapid footfalls a short distance in advance of us. I clutched Käspar’s arm. He nodded.

Almost breathless, I was conscious that we were no longer treading upon pavement, but on boards and amid a confusion of lumber. In front of us were no more lights; only blank vacancy. Käspar gave one mighty spring. He clutched, missed, and fell back with a cry of horror.

There was a dull splash in the black waters of the river at our feet.