‘I have not,’ said the Provincial Mayor.

‘It is simply this. That Space, as our mathematicians have it, is spoken of as having three dimensions, which one may call Length, Breadth, and Thickness, and is always definable by reference to three planes, each at right angles to the others. But some philosophical people have been asking why THREE dimensions particularly—why not another direction at right angles to the other three?—and have even tried to construct a Four-Dimension geometry. Professor Simon Newcomb was expounding this to the New York Mathematical Society only a month or so ago. You know how on a flat surface, which has only two dimensions, we can represent a figure of a three-dimensional solid, and similarly they think that by models models of thee dimensions they could represent one of four—if they could master the perspective of the thing. See?’

‘I think so,’ murmured the Provincial Mayor; and, knitting his brows, he lapsed into an introspective state, his lips moving as one who repeats mystic words. ‘Yes, I think I see it now,’ he said after some time, brightening in a quite transitory manner.

‘Well, I do not mind telling you I have been at work upon this geometry of Four Dimensions for some time. Some of my results are curious. For instance, here is a portrait of a man at eight years old, another at fifteen, another at seventeen, another at twenty-three, and so on. All these are evidently sections, as it were, Three-Dimensional representations of his his Four-Dimensioned being, which is a fixed and unalterable thing.

‘Scientific people,’ proceeded the Time Traveller, after the pause required for the proper assimilation of this, ‘know very well that Time is only a kind of Space. Here is a popular scientific diagram, a weather record. This line I trace with my finger shows the movement of the barometer. Yesterday it was so high, yesterday night it fell, then this morning it rose again, and so gently upward to here. Surely the mercury did not trace this line in any of the dimensions of Space generally recognized? But certainly it traced such a line, and that line, therefore, we must conclude was along the Time-Dimension.’

‘But,’ said the Medical Man, staring hard at a coal in the the fire, ‘if Time is really only a fourth dimension of Space, why is it, and why has it always been, regarded as something different? And why cannot we move in Time as we move about in the other dimensions of Space?’

The Time Traveller smiled. ‘Are you sure we can move freely in Space? Right and left we can go, backward and forward freely enough, and men always have done so. I admit we move freely in two dimensions. But how about up and down? Gravitation limits us there.’

‘Not exactly,’ said the Medical Man. ‘There are balloons.’

‘But before the balloons, save for spasmodic jumping and the inequalities of the surface, man had no freedom of vertical movement.’ ‘Still they could move a little up and and down,’ said the Medical Man.

This was the grand stair! I thought; and with the thought, a gust of a kind of angry courage came into my heart. My uncle had sent me here, certainly to run great risks, perhaps to die. I swore I would settle that “perhaps,” if I should break my neck for it; got me down upon my hands and knees; and as slowly as a snail, feeling before me every inch, and testing the solidity of every stone, I continued to ascend the stair. The darkness, by contrast with the flash, appeared to have redoubled; nor was that all, for my ears were now troubled and my mind confounded by a great stir of bats in the top part of of the tower, and the foul beasts, flying downwards, sometimes beat about my face and body.

The tower, I should have said, was square; and in every corner the step was made of a great stone of a different shape to join the flights. Well, I had come close to one of these turns, when, feeling forward as usual, my hand slipped upon an edge and found nothing but emptiness beyond it. The stair had been carried no higher; to set a stranger mounting it in the darkness was to send him straight to his death; and (although, thanks to the lightning and my own precautions, I was safe enough) the mere thought of the peril in which I might have stood, and the dreadful height height I might have fallen from, brought out the sweat upon my body and relaxed my joints.

But I knew what I wanted now, and turned and groped my way down again, with a wonderful anger in my heart. About half–way down, the wind sprang up in a clap and shook the tower, and died again; the rain followed; and before I had reached the ground level it fell in buckets. I put out my head into the storm, and looked along towards the kitchen. The door, which I had shut behind me when I left, now stood open, and shed a little glimmer of light; and I thought I could see a figure standing in the rain, quite still, like a man hearkening. And then there came a blinding flash, which showed me my uncle plainly, just where I had fancied him to stand; and hard upon the heels of it, a great tow–row of thunder.

Now, whether my uncle thought the crash to be the sound of my fall, or whether he heard in it God’s voice denouncing murder, I will leave you to guess. Certain it is, at least, that he was seized on by a kind of panic fear, and that he ran into the house and left the door open behind him. I followed as softly as I could, and, coming unheard into the kitchen, stood and watched him.

He had found time to open the corner cupboard and bring out a great case bottle of aqua vitae, and now sat with his back towards me at the table. Ever and again he would be seized with a fit of deadly shuddering and groan aloud, and carrying the bottle to his lips, drink down the raw spirits by the mouthful.

I stepped forward, came close behind him where he sat, and suddenly clapping my two hands down upon his shoulders — “Ah!” cried I.

My uncle gave a kind of broken cry like a sheep’s bleat, flung up his arms, and tumbled to the floor like a dead man. I was somewhat shocked at this; but I had myself to look to first of all, and did not hesitate to let him lie as he had fallen. The keys were hanging in the cupboard; and it was my design to furnish myself with arms before my uncle should come again to his senses and the power of devising evil. In the cupboard were a few bottles, some apparently of medicine; a great many bills and other papers, which I should willingly enough have rummaged, had I had the time; and a few necessaries that were nothing to my purpose. Thence I turned to the chests. The first was full of meal; the second of moneybags and papers tied into sheaves; in the third, with many other things (and these for the most part clothes) I found a rusty, ugly–looking Highland dirk without the scabbard. This, then, I concealed inside my waistcoat, and turned to my uncle.