Van Damm said nothing in reply but went to the smoothly burnished balcony of the bridge, which ran in a shining, slightly curved arc to the further shore. He gazed down into the turgid, rippling water, which gave off a slight luminescence. There was a current here and it ran back in the direction from which we had come. I ventured to say that this river probably drained into the lake which we had crossed and was gratified to learn that the leaders of the party were already of the same opinion.
Nothing showed on the surface of the river; there appeared to be no life in the depths; and no flotsam or any other debris was carried down. At least, not while we were there and we lingered for an hour in that strange spot.
At last we moved on, reaching the far shore without incident. I looked back towards the city but it was already lost in the haze. I could not help reflecting, with a sinking of the heart, that we were committing ourselves more and more into the interior of this bizarre and terrible place, with every day that passed; if anything malignant were encountered it would be very difficult, if not impossible to fight the long miles back.
We lunched on the opposite bank of the stream, where there were no buildings or vegetation of any kind, just the bare unyielding rock and sandy particles of grit to which we had long become used. Scarsdale had decided by this time that we would continue in the northwards direction together and to do this it was necessary that Holden rejoin us. I contacted him by radio — we had been in touch at intervals all the morning — and Van Damm said that he would go back. The two men would then load the machine-gun and heavy equipment on the trolley and rejoin us in the afternoon.
Van Damm had been gone several minutes and had in fact disappeared in the haze across the bridge only a short while before when there came a sudden stammer from the machine- ' gun which reverberated and echoed in the most awful way across the miles of caverns. There were separate and distinct bursts but the muted thunder of the explosions was constantly repeated under the cave roof and created such a menacing effect that our party instinctively cowered away as though we ourselves were under fire.
The noise was so unexpected and so shocking that none of us could at first think what it meant; that Holden had fired at something was obvious but this underground atmosphere was so arid and lifeless that it was difficult to think of a possible target.
I found Prescott at my side; his suggestion was that of a signal but Scarsdale immediately ruled that out as Holden had only to use his radio. We expected Van Damm would immediately hurry on to Holden's assistance and indeed he came through on his handset almost at once. I then tried to reach Holden on the radio link but with no success.
'Keep trying,' Scarsdale told me, almost savagely. His bearded face looked more like a Viking than ever as he gazed about him, his revolver cocked and ready for use. I remembered then the fate of the dwarf Zalor and realised what had never been absent from our leader's mind; that this underground world harboured many ancient and evil things which would only reveal themselves when they were ready.
'Has Holden been attacked, do you think?' Prescott asked the Professor.
Scarsdale shook his head impatiently. 'We shall know in good time,' he said crisply. 'I blame myself for splitting the party. Holden was possibly the wrong person to leave on his own like this. His nerves have been uneven ever since we found the dwarf”s body.'
I looked at him in surprise as it was the first time he had ever directly mentioned the incident.
I shall never forget the long hour we sat by the bridge parapet, looking across the stygian water and listening to the incessant crackle of the radio set; my own nerves were stretched high and I expected minute by minute to hear another shattering series of explosions from the machine-gun. But nothing came and my tension eventually died away.
Then, at about two o'clock in the afternoon to our intense relief we heard Holden's voice on the radio. He apologised for what he knew must have been a startling incident. He had fired, he said, at something which was moving towards him between the buildings at the edge of the plaza. He had then gone off to investigate, leaving the radio, and had only just returned.
Scarsdale moved to take the microphone from me at this point. I forget his exact words but his clipped tones and reproving, if urbane, remarks had the desired effect; Holden did not afterwards forget the Professor's strict instructions.
'Well,' he said at length. 'There appears to be no harm done and I think you can take it that anything down here would be alien to human life as we know it. We will not come back but I'll await your report when you return with the doctor.'
Scarsdale instructed Holden to dismantle the equipment; he and Van Damm could then investigate the area further on their way to re-join us. He would keep the radio link open constantly from now on. A few minutes later Van Damm's tetchy voice came through. When the two men came across the bridge pushing the trolley full of heavy equipment later in the afternoon, Holden told his story in person to Scarsdale as we all crowded round. He had been sitting in the square making notes, he said, when he became aware of some faint shadowy thing which appeared to flit between the far buildings at the end of the plaza.
The occurrence was so unusual that he kept watch on the one point for several minutes; he had thought that it was the optical illusion which we had found common to the city but he soon realised that a large 'hopping thing' as he described it, was moving about between the block-like structures at the edge of the square and gradually coming closer. Not surprisingly, he did not like this, and rapidly got behind the machine-gun.
After another quarter of an hour passed, the thing, which appeared to be grey in hue and of enormous size, stood still; Holden got the uncomfortable impression that he himself was being studied and he reached for his binoculars. He had difficulty in focusing the glasses but as soon as the thing began to come into reasonably clear view, its aspect was so disturbing that Holden became greatly agitated and was unable to hold the binoculars properly. It was only a few seconds after that before he let off a burst with the machine- gun, followed by two others, as the thing made off into the distance.
Courageously, under the circumstances, but foolishly as it now appeared, Holden then set off with one of the elephant rifles to see whether he had wounded the creature. The satisfying noise of the machine-gun had given him back his courage and he hoped to find whether he had hit it. He did find one or two of the flattened bullets from the gun lying at the edge of the square but so far as he could see, there was no sign of the creature and of course the buildings themselves were of too hard a material for the impact of the bullets to make any impression on them.
It was only after he had reported to us on the radio and Van Damm had reached him that they had seen any other evidence of the creature. He and Van Damm had taken a slightly different route out of the city, in order to pass by the spot where the hopping thing had been seen.
'There was a trail of slime leading off the edge of the square,' said Van Damm grimly. 'The stench was awful and we didn't follow it up.'
Fifteen
We didn't talk much about this among ourselves. As if by tacit consent each member of the Great Northern Expedition busied himself with the work in hand. Scarsdale wanted to press on to the limit of exploration in the northern direction; that was his prime purpose in mounting the project at all, he emphasised. We would be able to take in the ancient city of Croth on the return journey; he planned to spend a month charting, photographing and investigating every last building and artefact, he assured us.
There would also be a system of 'leave', with two members at a time returning to the outside air for a fortnight, both for relaxation and to safeguard the lines of communication. This seemed an excellent idea to me as I for one found the life underground oppressive and chilling, with the never- changing light and the haunting silence, broken only by the faint thumping of the great pulse in distance.
Scarsdale also made the implicit promise in his remarks that we would deal with the strange creature seen by Holden on our return; that there might be more of them and that somehow they might prevent our return to the outside world did not seem to have occurred to him. Or rather, to correct myself, I was sure that it had, but that he did not want to go into any detailed explanation for reasons of his own. I remembered then that the Great Northern
