I had sustained no injuries apart from a few slight bruises. Passersby helped me to my feet, while, in that other city, pedestrians performed the same service for my strange double.

I repeated the experiment under varying conditions, in city and country. Always I saw my ultra-dimensional double, in an equivalent situation, duplicating my actions. It seemed that there was no person, animal, plant, machine, building, landscape, in our world which did not have its counterpart in the other. All happenings occurred coincidentally in the two spheres.

Then came the astounding change. I had deferred taking the drug for some days, realizing that my health had suffered too heavily from its use and that death might soon follow if I persisted in further experiments. During that time I had experienced some strange mental states, which I could not recall clearly afterwards. Also, there had been several odd lapses of consciousness, lasting for several hours, which were always preceded by mental confusion and a preoccupation with thoughts remote from my usual trend. In particular, there would come to me the thought of an absolute vacuum, between the worlds, apart from time and place. Through superior, godlike will-power, it seemed to me, a being might enter this vacuum and thus insulate himself from the cosmic laws that would otherwise control his destiny. Such insulation seemed desirable to me, and I would find myself willing it intently just as consciousness deserted me. Thus alone could I divorce my actions from those of the otherworld being, and escape the doom which menaced us both through repeated use of the powerful compound drug.

Feeling still too weak and ill to go out, I made the next experiment with the drug in my laboratory, lying on the couch. The drug acted as usual, the vision clarifying itself till I saw once more the vessels and furniture of that alien laboratory beyond my own. But, to my amazement, the vast, many-cubed couch, on which I had thought to see a reclining figure, was vacant! I looked everywhere about the place, but in vain, for the companion of my visions.

Then, for the first time in my use of the super-drug, I experienced the sensation of hearing. A voice began to speak, low, toneless, coming from no direction—and yet from all directions. Sometimes I thought it spoke in my own brain, rather than from any point in space. It said:

“Can you hear me? I am Abernarda Chameechamach, your twin in the four-dimensioned cosmos you have visioned.”

“Yes, I can hear you,” I replied. “Where are you?” Whether I spoke aloud, or merely thought the words, I am not sure.

“I have isolated myself in the vacuum of super-space,” was the answer. “It is the only way in which I can break the rapport between our existences—which must be broken if I am to escape the death that threatens you. In this vacuum, all laws and all forces are inoperative, except those of thought and will. I can will myself into the vacuum and out of it again. My thoughts can pass to your world and become audible to you in your present state under the influence of the drug.”

“But how can you do these things independently of me?” I asked.

“Because my will and my brain are superior to yours, though otherwise identical with them. Our worlds are twin, as you have realized; but mine, which has one more dimension than yours, is the primary one, the world of causes. Yours is the secondary world of effects. It was I who invented the super-drug, in my efforts to stimulate a new sense that would reveal cosmic reality. Your invention of it was the result of mine, just as your existence is the result of my existence. I alone of the people in this world, through the drug, have learned that there is a secondary sphere; and you alone, in yours, have visioned the primary sphere. My knowledge, through a law of the higher dimension, enables me to act now upon the secondary world through thought alone. Insulating myself in this vacuum, I have willed that you should perform actions from whose necessity I myself am exempt. Several times the only result was a loss of consciousness on your part, corresponding to my stay in the vacuum. But now I have triumphed. You have taken the drug, while I stand aloof between the worlds, invisible, and apart from the chain of cause and effect.”

“Since you have not used the drug,” I asked, “how is it that you are conscious of me? Can you see me?”

“No, I cannot see you. But I am aware of you through a sense not dependent upon the drug: a sense that my very knowledge of your existence enables me to use. It is part of my superior mind power. I do not intend to use the drug again; but I wish that you shall continue to use it.”

“Why?” I queried.

“Because you will soon die from the effects of such use. I, abstaining, will escape death. Such a thing, I believe, has never before happened in the history of the double cosmos. Death, in your world, like birth and everything else, has always been the concomitant of a like happening in mine. What the outcome will be, I am not quite sure. But, by breaking the nexus between us, and outliving you, it may be that I shall never die.”

“But is my death possible without yours?” I questioned.

“I think that it is. It will result from the continuation of actions that would also cause my death, if I did not choose to interrupt them in myself. When your death approaches, I shall enter the vacuum again, where no cosmic cause or consequence can follow me. Thus I shall be doubly safe.”

For several hours past, I have been writing this account at my laboratory desk. Whatever happens to me—whether death or something stranger than death—a record of my incredible experiences will at least remain when I am gone.

Since my conversation with the being who calls himself Abernarda Chameechamach, I have tried to abstain wholly from the super-drug and have several times delayed yielding to the impulse that makes me continue its use. I find myself wishing, willing intensely that Abernarda Chameechamach should take the drug while I refrain, and should perish in my stead.

During my few recent experiments with the drug, I have seen only the empty laboratory of my trans-dimensional twin. Apparently, on each occasion, that being has absented himself in super-space. He has not spoken to me again.

However, I have a strange feeling that I am closer to him than at any time during our mutual visions or our one conversation. My physical enfeeblement has progressed pace by pace with a remarkable strengthening and enlargement of my mental faculties. It seems, indescribably, that another dimension has been added to my mind. I feel myself the possessor of senses beyond the normal five and the one activated by the drug. I believe that the powers of Abernarda Chameechamach, though directed against me, have to some extent passed into me through a cosmic law that not even he is able to abrogate from his station beyond time and place. There is a balance that must right itself, even though temporarily disturbed by the unknown forces of a four-dimensioned mind.

His very volition has transferred itself to me, and has turned back against him, though I am subject to him in ways already indicated. I am possessed by the image of the cosmic vacuum in which he isolates himself. More and more I feel in myself the desire, the will and the power to project myself bodily into the vacuum, and thus escape the chain of consequences that began with the discovery of the super-drug.

What, I wonder, will happen if I should escape in this manner before the drug kills me? What will happen to me, and to Abernarda Chameechamach, if we should meet face to face in that void between the worlds of our double cosmos?

Will the meeting mean annihilation for us both? Will we survive as two entities—or a single entity? I can only wait and conjecture.

Does that other also doubt and wonder while he waits?