This promise was rapidly given by all of us, of course, and when we had each stowed the goggles away where they could easily be reached, we resumed our march.
Holden turned to me as we walked together, pulling the trolley. I could see his face more clearly now and was shocked to note that there were dark shadows under his eyes and his lips were a startling white. He seemed but the shadow of the man who had set out with us so enthusiastically from the Professor's Surrey home; looking back on that hectic period it seemed to me now that it had taken place not only long ago but on another planet, so alien and bizarre were our present surroundings. Most of us too had lost all sense of time and we could have been many weeks here, instead of the minutely documented days that we had spent beneath the surface of the earth. Even the time since leaving Croth seemed infinitely distant.
I put my face close to Holden as he mumbled something; his ravaged features looked like a steel engraving in the slowly growing light. I had to ask him to repeat his sentence, his words were so slow and hesitant.
What I eventually made out was the broken sentence, 'I cannot go on.'
I looked at him sharply. I saw now that he was trembling slightly as though he were suffering from fever. There had been such a marked deterioration in him since I had last had occasion to observe him a few days earlier that I was startled. But of course the dimness of the light in which we had previously been immured would have made it difficult to observe his condition in detail. I stopped abruptly as my companion's legs gave; the trolley veered and tipped against the wall of the tunnel with a sharp grating sound. Holden's knees buckled and he tried feebly to support himself with one hesitant hand on the metal railing of the trolley, failed and slipped to the ground in an insensate heap.
My shout brought Scarsdale and the others running back towards me. I had already turned Holden over but Scarsdale elbowed me aside with a muttered apology. I busied myself in removing the trolley so that the Professor and Van Damm could examine our companion properly. There was little further I could do so I stood off at a distance with Prescott while the two scientists busied themselves over the huddled form on the tunnel floor. One foot of the recumbent man lay at a grotesque angle.
Van Damm got up presently and fumbled among the kit on the trolley.
'Is there anything I can do to help?' I asked him.
The doctor shook his head. He looked puzzled.
'He's fainted but there is more to it than that,' he said. 'Apart from nerves, that is.'
He paused as though he had said too much.
'I know he had a bad shock when we found the dwarf's body,' I said. 'There's no secret about that.'
My manner must have seemed a little short for the doctor shot me a sharp, shrewd glance.
'I don't mean only that, my dear Plowright,' he said. 'Holden was one of the fittest men along on this party. If I didn't know better I'd say he was suffering from some form of pernicious anaemia. He's in a comatose condition. I'd say he's collapsed from sheer physical exhaustion. His nerves were strung-up, yes, but this is not the cause of his condition.'
He refused to be drawn any further and went back to the two men, taking the flash of brandy with him. Prescott and I stood in the strengthening light that flooded from the long tunnel before us and waited for the verdict.
Sixteen
In the end it was arranged that Van Damm would stay with Holden while Prescott and I, led by the Professor, would press on towards the strengthening light which beckoned in front of us. It took some element of self-sacrifice on the part of Van Damm to suggest remaining behind and I was near to admiring him at that moment. Despite the assumed waspishness between the two of them Scarsdale and Van Damm were close, and they had together hammered out a successful formula for the Great Northern Expedition. It seemed as though Van Damm had cheated himself of the shared glory if we now discovered something even more extraordinary in the growing luminescence of that subterranean place.
Moved by these and other considerations I had myself volunteered to remain behind with Holden, who was now conscious and able to speak. But I was immediately overruled by the two heads of the expedition; apart from being deputy leader Van Damm also had specialist medical knowledge. What could I do if there were some emergency beyond my own sparse rudiments of first-aid? No, said Scarsdale, it would not do; besides, he added sotto voce to me, as we stood alone for a moment, apart from the others, he might have need of my agility and strength at the front.
Prescott was experienced in the use of firearms and would be needed also; so it was arranged. We presently set off, led by the Professor carrying a naked revolver, followed closely behind by Prescott and myself pushing the trolley. In addition to the light machine-gun, ready on its tripod, Scarsdale had also laid out a number of hand grenades within easy reach. I watched these grim preparations with growing disquiet. I did not know what the Professor expected to find but it was obviously something large and inimical to human life if we needed protection on this scale.
We had gone only a few hundred yards beyond the point where we had left our two companions before there was an appreciable strengthening of the light; not only its intensity but its quality. It had a flickering, throbbing property which was hard on the eyes; it seemed to pulsate in time with the vibrating pulse which beat ahead of us with ever-increasing strength.
We could now see our way quite clearly by this illumination; the branching tunnels still led away to left and right but there was no doubt that the one we were following was the correct one; it led, despite slight curvatures to either side, unerringly to the north and both the light and the throbbing pulse which had the strength of a muted kettledrum played at a distance, undoubtedly emanated from this source. I did, in fact, at Scarsdale's suggestion, try one of the branching tributaries to the right but the light faded in a very few seconds and the vibrating rhythm of the pulse-beat with it.
Prescott now drew to my attention some more of the curiously incised hieroglyphs which were carved at various points on the side of the tunnel we were following; I wondered perhaps whether they might be distance marks but the Professor thought not. He puzzled at them for a few minutes and then announced sharply that they were mathematical formulae whose purpose for the moment escaped him. I gave him a long searching glance and by the way he lowered his eyelids I felt that he was not speaking the truth.
The markings appeared to me to be no different to the other inscriptions in the ancient language and I could see no formulae which would make any mathematical symbols. However, I guessed that the Professor had his own reasons for not translating the signs; it may have been that they had a sinister import and that he had no wish to alarm us.
I did, however, persuade him and Prescott to pose for some pictures by one of the plaques and then changed round to allow Prescott to photograph myself with the Professor. As it turned out this was the only picture of the expedition to survive which showed myself. By now we had little or no need of any artificial illumination and could see perhaps a quarter of a mile ahead along the tunnel. It was this factor — and thank God for it — which was instrumental in saving our lives.
A sudden shout from Prescott put my nerves on edge. He was at my elbow, pointing.
'There, man, there. The slime trails!'
I saw what he meant a moment later, before the awful stench was brought to us on the warmth of the strengthening wind. Great, slug-like smears on the surface of the tunnel which led off into unknown debouchments at the side.