A ladder at the far end led to a loft, only a few feet above the living-space, and looking up I could see straw pallets laid upon the planking. The fire, stacked with turf and furze, lay in a recess let into the wall, and a stew-pot simmered above the smoke, slung between iron bars fixed to the earthen floor. A girl, her lank hair falling below her shoulders, was kneeling by the fire, and as the horseman called a greeting she looked up at him and smiled.

I was close upon his heels, and suddenly he turned, staring straight at me, shoulder to shoulder. I could feel his breath upon my cheek, and I put out one hand, instinctively, to fend him off. I felt a sudden sharp pain on my knuckles and saw that they were bleeding, and at the same time I heard a splintering of glass. He was not there any longer, neither he, nor the girl, nor the smoking fire, and I had driven my right hand through one of the windows of the disused kitchen in Kilmarth's basement, and was standing in the old sunken courtyard beyond.

I stumbled through the open door of the boiler-room, retching violently, not at the sight of blood but because I was seized with an intolerable nausea, rocking me from head to foot. Throbbing in every limb, I leant against the stone wall of the boiler-room, the trickle of blood from my cut hand running down to my wrist.

In the library overhead the telephone began to ring, sounding, in its insistency, like a summons from a lost, unwanted world. I let it ring.

CHAPTER TWO

IT MUST HAVE taken the best part of ten minutes for the nausea to pass. I sat on a pile of logs in the boiler-room waiting. The worst thing about it was the vertigo: I dared not trust myself to stand. My hand was not badly cut, and I soon staunched the blood with my handkerchief. I could see the splintered window from where I sat, and the fragments of glass on the patio beyond. Later on I might be able to reconstruct the scene, judge where my horseman had been standing, measure the space of that long vanished house where there were now patio and basement: but not now. Now I was too exhausted.

I wondered what sort of figure I must have cut, if anyone had seen me walking over the fields and across the road at the bottom of the hill, and climbing the lane to Tywardreath. That I had been there I was certain. The state of my shoes, the torn cloth of one trouser leg, and my shirt clammy cold with sweat — this had not come about from a lazy amble on the cliffs.

Presently, the nausea and vertigo having passed, I walked very slowly up the back stairs to the hall above. I went into the lobby where Magnus kept his oilskins and boots and all the rest of his junk, and stared at myself in the looking-glass above the wash-basin. I looked normal enough. A bit white about the gills, nothing worse. I needed a stiff drink more than anything. Then I remembered that Magnus had said: Don't touch alcohol for at least three hours after taking the drug, and then go slow. Tea would be a poor second-best, but it might help, and I went into the kitchen to make myself a cup. This kitchen had been the family dining-room when Magnus was a boy; he had converted it during recent years. While I waited for the kettle to boil I looked out of the window at the courtyard below. It was a paved enclosure, surrounded by old, moss-encrusted walls. Magnus, in a burst of enthusiasm at some time, had attempted to turn it into a patio, as he called it, where he could flop about nude if a heat-wave ever materialised. His mother, he told me, had never done anything about the enclosure because it led out from what were then the kitchen quarters.

I looked upon it now with different eyes. Impossible to recapture what I had so lately seen — that muddied yard, with the cow-house adjoining, and the track leading to the wooded grove above. Myself following the horseman through the trees. Was the whole thing hallucination engendered by that hell-brew of a drug? As I wandered, mug in hand, through to the library, the telephone started to ring again. I suspected it might be Magnus, and it was. His voice, clipped and decisive as always, stood me in greater stead than the drink I could not have, or the mug of tea. I flung myself down in a chair and prepared for a session.

"I've been ringing you for hours," he said. "Had you forgotten you promised to put through a call at half-past three?"

I had not forgotten, I told him. "The fact is, I was otherwise engaged."

"So I imagined. Well?"

The moment was one to savour. I wished I could keep him guessing. The thought gave me a pleasing sensation of power, but it was no use, I knew I had to tell him.

"It worked," I said. "Success one hundred per cent." I realised, from the silence at the other end of the line, that this piece of information was totally unexpected. He had visualised failure. His voice, when it came, was pitched in a lower key, almost as though he were talking to himself.

"I can hardly believe it," he said. "How absolutely splendid." And then, taking charge, as always, "You did exactly as I told you, followed the instructions? Tell me everything, from the beginning… Wait, though, are you all right?"

"Yes," I said, "I think so, except that I feel bloody tired, and I've cut my hand, and I was nearly sick in the boiler-room."

"Minor matters, dear boy, minor matters. There's often a feeling of nausea afterwards, it soon passes. Go on."

His impatience fed my own excitement, and I wished he had been in the room beside me instead of three hundred miles away.

"First of all," I said, enjoying myself, "I've seldom seen anything more macabre than your so-called lab. Bluebeard's chamber would be an apter description for it. All those embryos in jars, and that revolting monkey's head.."

"Perfectly good specimens and extremely valuable," he interrupted, "but don't get side-tracked. I know what they are for: you don't. Tell me what happened."

I took a sip of my rapidly cooling tea, and put down the mug.

"I found the row of bottles," I continued, "all in the locked cupboard. Neatly labelled, A, B, C. I poured exactly three measures from A into the medicine-glass, and that was that. I swallowed it, replaced the bottle and glass, locked the cupboard, locked the lab, and waited for something to happen. Well, nothing did." I paused, to let this information sink in. No comment from Magnus.

"So," I went on, "I went into the garden. Still no reaction. You told me the time factor varied, that it could be three minutes, five, ten, before anything happened. I expected to feel drowsy, although you hadn't specifically mentioned drowsiness, but as nothing seemed to be happening I thought I would go for a stroll. So I climbed over the wall by the summer-house into the field, and began to walk in the direction of the cliffs."

"You damn fool," he said. "I told you to stay in the house, at any rate for the first experiment."

"I know you did. But, frankly, I wasn't expecting it to work. I planned to sit down, if it did, and drift off into some delightful—"

"Damn fool," he said again. "It doesn't happen that way."

"I know it doesn't, now," I said.

Then I described my whole experience, from the moment the drug took effect to the smashing of the glass in the basement kitchen. He did not interrupt me at all except to murmur, when I paused for breath and a sip of tea, "Go on.. go on.."

When I had finished, including the aftermath in the boiler-room, there was complete silence, and I thought we had been cut off. "Magnus," I said, "are you there?"

His voice came back to me, clear and strong, repeating the same words that he had used at the start of our telephone session.

"How splendid," he said. "How absolutely splendid. Perhaps…" The truth was that I was completely drained, exhausted, having been through the whole process twice.

He began to talk rapidly, and I could just imagine him sitting at that desk of his in London, one hand holding the receiver, the other reaching out for his inevitable doodling-pad and pencil.

"You realise", he said, "that this is the most important thing that has happened since the chemical boys got hold of teonanacatl and ololiuqui? These only push the brain around in different directions — quite chaotic. This is controlled, specific. I knew I was on to something potentially tremendous, but I couldn't be sure, having only tried it on myself, that it wasn't hallucinogenic. If this was so, you and I would have had similar physical reactions — loss of touch, greater intensity of vision, and so on — but not the same experience of altered time. This is the important thing. The tremendously exciting thing."

"You mean", I said, "that when you tried it on yourself you also went back in time? You saw what I did?"

"Precisely. I didn't expect it any more than you did. No, that's not true, because an experiment I was working on then made it remotely possible. It has to do with D.N.A., enzyme catalysts, molecular equilibria and the like — above your head, dear boy, I won't elaborate — but the point that interests me at the moment is that you and I apparently went into an identical period of time. Thirteenth or fourteenth century, wouldn't you say, judging from their clothes? I too saw the chap you describe as your horseman — Roger, didn't the Prior call him? — the rather slatternly girl by the fire, and someone else as well, a monk, which immediately suggested a tie-up with the mediaeval priory that was once part of Tywardreath. The point is this: does the drug reverse some chemical change in the memory systems of the brain, throwing it back to a particular thermodynamic situation which existed in the past, so that the sensations elsewhere in the brain are repeated? If it does, why does the molecular brew return to that particular moment in time? Why not yesterday, five years ago, or a hundred and twenty years? It could be — and this is the thing that excites me — it could be that there is some very potent link connecting the taker of the drug with the first human image recorded in the brain, while under the drug's influence. In both our cases we saw the horseman. The compulsion to follow him was particularly urgent. You felt it, so did I. What I don't yet know is why he plays Virgil to our Dante in this particular Inferno, but he does, there's no escaping him. I've made the 'trip'—to use the students' phraseology — a number of times, and he's invariably there. You'll find the same thing happens on your next adventure. He always takes charge." The assumption that I was to continue acting as guineapig for Magnus did not surprise me. It was typical of our many years of friendship, both at Cambridge and afterwards. He called the tune, and I danced, in God only knew how many disreputable escapades in our undergraduate life together, and later when we went our separate ways, he to his career as a biophysicist and thence to a professorship at London University, I to the tamer routine of a publisher's office. My marriage to Vita three years ago had made the first break between us, possibly a salutary one for us both. The sudden offer of his house for the summer holidays, which I had accepted gratefully, being between jobs — Vita was urging me to accept a directorship in a flourishing New York publishing firm run by her brother, and I needed time to decide — now appeared to have strings attached. The long, lazy days with which he had baited me, lying about in the garden, sailing across the bay, were beginning to take on another aspect.