"He said that that was better. 'It is a personal fancy, and depends on your KNOWING that there is nothing between you and the top of the Dent Blanche. And you know because your eyes tell you there is nothing.

Even if you were blind, you might have a sort of sense about adjacent matter. Blind men often have it. But in any case, whether got from instinct or sight, the KNOWLEDGE is what matters.'

"Hollond was embarking on a Socratic dialogue in which I could see little point. I told him so, and he laughed. "'I am not sure that I am very clear myself. But yes--there IS a point. Supposing you knew-not by sight or by instinct, but by sheer intellectual knowledge, as I know the truth of a mathematical proposition--that what we call empty s.p.a.ce was full, crammed. Not with lumps of what we call matter like hills and houses, but with things as real--as real to the mind. Would you still feel crowded?'

"'No,' I said, 'I don't think so. It is only what we call matter that signifies. It would be just as well not to feel crowded by the other thing, for there would be no escape from it. But what are you getting at? Do you mean atoms or electric currents or what?'

"He said he wasn't thinking about that sort of thing, and began to talk of another subject.

"Next night, when we were pigging it at the Geant cabane, he started again on the same tack. He asked me how I accounted for the fact that animals could find their way back over great tracts of unknown country.

I said I supposed it was the homing instinct.

"'Rubbish, man,' he said. 'That's only another name for the puzzle, not an explanation. There must be some reason for it. They must KNOW something that we cannot understand. Tie a cat in a bag and take it fifty miles by train and it will make its way home. That cat has some clue that we haven't.'

"I was tired and sleepy, and told him that I did not care a rush about the psychology of cats. But he was not to be snubbed, and went on talking.

"'How if s.p.a.ce is really full of things we cannot see and as yet do not know? How if all animals and some savages have a cell in their brain or a nerve which responds to the invisible world? How if all s.p.a.ce be full of these landmarks, not material in our sense, but quite real? A dog barks at nothing, a wild beast makes an aimless circuit. Why?

Perhaps because s.p.a.ce is made up of corridors and alleys, ways to travel and things to shun? For all we know, to a greater intelligence than ours the top of Mont Blanc may be as crowded as Piccadilly Circus.'

"But at that point I fell asleep and left Hollond to repeat his questions to a guide who knew no English and a snoring porter.

"Six months later, one foggy January afternoon, Hollond rang me up at the Temple and proposed to come to see me that night after dinner. I thought he wanted to talk Alpine shop, but he turned up in Duke Street about nine with a kit-bag full of papers. He was an odd fellow to look at--a yellowish face with the skin stretched tight on the cheek-bones, clean-shaven, a sharp chin which he kept poking forward, and deep-set, greyish eyes. He was a hard fellow, too, always in pretty good condition, which was remarkable considering how he slaved for nine months out of the twelve. He had a quiet, slow-spoken manner, but that night I saw that he was considerably excited.

"He said that he had come to me because we were old friends. He proposed to tell me a tremendous secret. 'I must get another mind to work on it or I'll go crazy. I don't want a scientist. I want a plain man.'

"Then he fixed me with a look like a tragic actor's. 'Do you remember that talk we had in August at Chamonix--about s.p.a.ce? I daresay you thought I was playing the fool. So I was in a sense, but I was feeling my way towards something which has been in my mind for ten years. Now I have got it, and you must hear about it. You may take my word that it's a pretty startling discovery.'

"I lit a pipe and told him to go ahead, warning him that I knew about as much science as the dustman.

"I am bound to say that it took me a long time to understand what he meant. He began by saying that everybody thought of s.p.a.ce as an 'empty h.o.m.ogeneous medium.' 'Never mind at present what the ultimate const.i.tuents of that medium are. We take it as a finished product, and we think of it as mere extension, something without any quality at all.

That is the view of civilised man. You will find all the philosophers taking it for granted. Yes, but every living thing does not take that view. An animal, for instance. It feels a kind of quality in s.p.a.ce.

It can find its way over new country, because it perceives certain landmarks, not necessarily material, but perceptible, or if you like intelligible. Take an Australian savage. He has the same power, and, I believe, for the same reason. He is conscious of intelligible landmarks.'

"'You mean what people call a sense of direction,' I put in.

"'Yes, but what in Heaven's name is a sense of direction? The phrase explains nothing. However incoherent the mind of the animal or the savage may be, it is there somewhere, working on some data. I've been all through the psychological and anthropological side of the business, and after you eliminate the clues from sight and hearing and smell and half-conscious memory there remains a solid lump of the inexplicable.'

"Hollond's eye had kindled, and he sat doubled up in his chair, dominating me with a finger.

"'Here, then is a power which man is civilising himself out of. Call it anything you like, but you must admit that it is a power. Don't you see that it is a perception of another kind of reality that we are leaving behind us? ', Well, you know the way nature works. The wheel comes full circle, and what we think we have lost we regain in a higher form. So for a long time I have been wondering whether the civilised mind could not recreate for itself this lost gift, the gift of seeing the quality of s.p.a.ce. I mean that I wondered whether the scientific modern brain could not get to the stage of realising that s.p.a.ce is not an empty h.o.m.ogeneous medium, but full of intricate differences, intelligible and real, though not with our common reality.'

"I found all this very puzzling and he had to repeat it several times before I got a glimpse of what he was talking about.

"'I've wondered for a long time he went on 'but now quite suddenly, I have begun to know.' He stopped and asked me abruptly if I knew much about mathematics.

"'It's a pity,' he said,'but the main point is not technical, though I wish you could appreciate the beauty of some of my proofs. Then he began to tell me about his last six months' work. I should have mentioned that he was a brilliant physicist besides other things. All Hollond's tastes were on the borderlands of sciences, where mathematics fades into metaphysics and physics merges in the abstrusest kind of mathematics. Well, it seems he had been working for years at the ultimate problem of matter, and especially of that rarefied matter we call aether or s.p.a.ce. I forget what his view was-atoms or molecules or electric waves. If he ever told me I have forgotten, but I'm not certain that I ever knew. However, the point was that these ultimate const.i.tuents were dynamic and mobile, not a mere pa.s.sive medium but a medium in constant movement and change. He claimed to have discovered--by ordinary inductive experiment--that the const.i.tuents of aether possessed certain functions, and moved in certain figures obedient to certain mathematical laws. s.p.a.ce, I gathered, was perpetually 'forming fours' in some fancy way.

"Here he left his physics and became the mathematician. Among his mathematical discoveries had been certain curves or figures or something whose behaviour involved a new dimension. I gathered that this wasn't the ordinary Fourth Dimension that people talk of, but that fourth-dimensional inwardness or involution was part of it. The explanation lay in the pile of ma.n.u.scripts he left with me, but though I tried honestly I couldn't get the hang of it. My mathematics stopped with desperate finality just as he got into his subject.

"His point was that the const.i.tuents of s.p.a.ce moved according to these new mathematical figures of his. They were always changing, but the principles of their change were as fixed as the law of gravitation.

Therefore, if you once grasped these principles you knew the contents of the void. What do you make of that?"

I said that it seemed to me a reasonable enough argument, but that it got one very little way forward. "A man," I said, "might know the contents of s.p.a.ce and the laws of their arrangement and yet be unable to see anything more than his fellows. It is a purely academic knowledge. His mind knows it as the result of many deductions, but his senses perceive nothing."

Leithen laughed. "Just what I said to Hollond. He asked the opinion of my legal mind. I said I could not p.r.o.nounce on his argument but that I could point out that he had established no trait d'union between the intellect which understood and the senses which perceived. It was like a blind man with immense knowledge but no eyes, and therefore no peg to hang his knowledge on and make it useful. He had not explained his savage or his cat. 'Hang it, man,' I said, 'before you can appreciate the existence of your s.p.a.cial forms you have to go through elaborate experiments and deductions. You can't be doing that every minute. Therefore you don't get any nearer to the USE of the sense you say that man once possessed, though you can explain it a bit.'"

"What did he say?" I asked.

"The funny thing was that he never seemed to see my difficulty. When I kept bringing him back to it he shied off with a new wild theory of perception. He argued that the mind can live in a world of realities without any sensuous stimulus to connect them with the world of our ordinary life. Of course that wasn't my point. I supposed that this world of s.p.a.ce was real enough to him, but I wanted to know how he got there. He never answered me. He was the typical Cambridge man, you know--dogmatic about uncertainties, but curiously diffident about the obvious. He laboured to get me to understand the notion of his mathematical forms, which I was quite willing to take on trust from him. Some queer things he said, too. He took our feeling about Left and Right as an example of our instinct for the quality of s.p.a.ce. But when I objected that Left and Right varied with each object, and only existed in connection with some definite material thing, he said that that was exactly what he meant. It was an example of the mobility of the s.p.a.cial forms. Do you see any sense in that?"

I shook my head. It seemed to me pure craziness.

"And then he tried to show me what he called the 'involution of s.p.a.ce,'

by taking two points on a piece of paper. The points were a foot away when the paper was flat, they coincided when it was doubled up. He said that there were no gaps between the figures, for the medium was continuous, and he took as an ill.u.s.tration the loops on a cord. You are to think of a cord always looping and unlooping itself according to certain mathematical laws. Oh, I tell you, I gave up trying to follow him. And he was so desperately in earnest all the time. By his account s.p.a.ce was a sort of mathematical pandemonium."

Leithen stopped to refill his pipe, and I mused upon the ironic fate which had compelled a mathematical genius to make his sole confidant of a philistine lawyer, and induced that lawyer to repeat it confusedly to an ignoramus at twilight on a Scotch hill. As told by Leithen it was a very halting tale.

"But there was one thing I could see very clearly," Leithen went on, "and that was Hollond's own case. This crowded world of s.p.a.ce was perfectly real to him. How he had got to it I do not know. Perhaps his mind, dwelling constantly on the problem, had unsealed some atrophied cell and restored the old instinct. Anyhow, he was living his daily life with a foot in each world.

"He often came to see me, and after the first hectic discussions he didn't talk much. There was no noticeable change in him--a little more abstracted perhaps. He would walk in the street or come into a room with a quick look round him, and sometimes for no earthly reason he would swerve. Did you ever watch a cat crossing a room? It sidles along by the furniture and walks over an open s.p.a.ce of carpet as if it were picking its way among obstacles. Well, Hollond behaved like that, but he had always been counted a little odd, and n.o.body noticed it but me.

"I knew better than to chaff him, and had stopped argument, so there wasn't much to be said. But sometimes he would give me news about his experiences. The whole thing was perfectly clear and scientific and above board, and nothing creepy about it. You know how I hate the washy supernatural stuff they give us nowadays. Hollond was well and fit, with an appet.i.te like a hunter. But as he talked, sometimes--well, you know I haven't much in the way of nerves or imagination--but I used to get a little eerie. Used to feel the solid earth dissolving round me. It was the opposite of vertigo, if you understand me--a sense of airy realities crowding in on you-crowding the mind, that is, not the body.

"I gathered from Hollond that he was always conscious of corridors and halls and alleys in s.p.a.ce, shifting, but shifting according to inexorable laws. I never could get quite clear as to what this consciousness was like. When I asked he used to look puzzled and worried and helpless. I made out from him that one landmark involved a sequence, and once given a bearing from an object you could keep the direction without a mistake. He told me he could easily, if he wanted, go in a dirigible from the top of Mont Blanc to the top of Snowdon in the thickest fog and without a compa.s.s, if he were given the proper angle to start from. I confess I didn't follow that myself. Material objects had nothing to do with the s.p.a.cial forms, for a table or a bed in our world might be placed across a corridor of s.p.a.ce. The forms played their game independent of our kind of reality. But the worst of it was, that if you kept your mind too much in one world you were apt to forget about the other and Hollond was always barking his shins on stones and chairs and things.

"He told me all this quite simply and frankly. Remember his mind and no other part of him lived in his new world. He said it gave him an odd sense of detachment to sit in a room among people, and to know that nothing there but himself had any relation at all to the infinite strange world of s.p.a.ce that flowed around them. He would listen, he said, to a great man talking, with one eye on the cat on the rug, thinking to himself how much more the cat knew than the man."

"How long was it before he went mad?" I asked.

It was a foolish question, and made Leithen cross. "He never went mad in your sense. My dear fellow, you're very much wrong if you think there was anything pathological about him--then. The man was brilliantly sane. His mind was as keen is a keen sword. I couldn't understand him, but I could judge of his sanity right enough."

I asked if it made him happy or miserable.

"At first I think it made him uncomfortable. He was restless because he knew too much and too little. The unknown pressed in on his mind as bad air weighs on the lungs. Then it lightened and he accepted the new world in the same sober practical way that he took other things. I think that the free exercise of his mind in a pure medium gave him a feeling of extraordinary power and ease. His eyes used to sparkle when he talked. And another odd thing he told me. He was a keen rockclimber, but, curiously enough, he had never a very good head.

Dizzy heights always worried him, though he managed to keep hold on himself. But now all that had gone. The sense of the fulness of s.p.a.ce made him as happy--happier I believe--with his legs dangling into eternity, as sitting before his own study fire.

"I remember saying that it was all rather like the mediaeval wizards who made their spells by means of numbers and figures.

"He caught me up at once. 'Not numbers,' he said. "Number has no place in Nature. It is an invention of the human mind to atone for a bad memory. But figures are a different matter. All the mysteries of the world are in them, and the old magicians knew that at least, if they knew no more.'

"He had only one grievance. He complained that it was terribly lonely.

'It is the Desolation,' he would quote, 'spoken of by Daniel the prophet.' He would spend hours travelling those eerie shifting corridors of s.p.a.ce with no hint of another human soul. How could there be? It was a world of pure reason, where human personality had no place. What puzzled me was why he should feel the absence of this. One wouldn't you know, in an intricate problem of geometry or a game of chess. I asked him, but he didn't understand the question. I puzzled over it a good deal, for it seemed to me that if Hollond felt lonely, there must be more in this world of his than we imagined. I began to wonder if there was any truth in fads like psychical research. Also, I was not so sure that he was as normal as I had thought: it looked as if his nerves might be going bad.

"Oddly enough, Hollond was getting on the same track himself. He had discovered, so he said, that in sleep everybody now and then lived in this new world of his. You know how one dreams of triangular railway platforms with trains running simultaneously down all three sides and not colliding. Well, this sort of cantrip was 'common form,' as we say at the Bar, in Hollond's s.p.a.ce, and he was very curious about the why and wherefore of Sleep. He began to haunt psychological laboratories, where they experiment with the charwoman and the odd man, and he used to go up to Cambridge for seances. It was a foreign atmosphere to him, and I don't think he was very happy in it. He found so many charlatans that he used to get angry, and declare he would be better employed at Mother's Meetings!"

From far up the Glen came the sound of the pony's hoofs. The stag had been loaded up and the gillies were returning. Leithen looked at his watch. "We'd better wait and see the beast," he said.

"... Well, nothing happened for more than a year. Then one evening in May he burst into my rooms in high excitement. You understand quite clearly that there was no suspicion of horror or fright or anything unpleasant about this world he had discovered. It was simply a series of interesting and difficult problems. All this time Hollond had been rather extra well and cheery. But when he came in I thought I noticed a different look in his eyes, something puzzled and diffident and apprehensive.

"'There's a queer performance going on in the other world,' he said.