At 800 feet the deep blue light remained but everything had taken on a ghostly form. Strange shadowy shapes flickered past and as the sphere descended further many of them began to show luminosity. When they came to rest at 1,600, five fishes swam past with blotches on them which glistened like tinfoil in the grey blue darkness then some unseen organism spat out a rocket-like burst of luminous fluid.
At 2,000 feet the Doctor put on the light for a few moments and a shoal of brilliant silver fish were caught in it turning like a flight of birds. Later they saw a creature with two large reddish lights in front and a constellation of smaller ones, all pale blue, then a great Squid with light organs encircling its eye, but the teeming life changed so constantly as the sphere was lowered that they caught little more than a glimpse of individual specimens and had no time to examine one tenth of all the marvels that passed the windows.
The Doctor judged that the day before they had been on the western fringe of the Atlantean city and he feared now that the drift of the ship might have carried them away from the area of its remains, but when they reached bottom at 10.40 he found to his joy that they were apparently well inside its limits. A line of tall rounded stones equal in circumference but uneven in height, rising quite near them from the ocean bed, definitely suggested a row of truncated columns.
By means of operating the claws in its undercarriage the Doctor turned the sphere gently and a solid surface, reaching up into the darkness like a great blank wall, came into view. For a moment he swivelled the light up and down but the beam could not reach its top and any ornamentations which it might once have had the waters had long since erased into a uniform smoothness.
As the sphere turned further the beam lit up an irregular pile of stones. All their corners and edges were rounded but they still suggested square and oblong blocks of masonry. Opposite the row of columns came a blank space where little was visible except the shadowy outline of more great monoliths in the distance; then a long smooth slope running upwards from the sea bottom at an angle of about thirty degrees and quite different in appearance from it. A dull iridescent sparkle which showed as the searchlight moved across its polished surface made it seem likely that it was a vast slab of granite. The columns appeared again and they had completed the circle.
'We are much handicapped,' remarked the Doctor, 'that the ship above can no longer move us as directed. I haf wished to make a tour of at least an hour before deciding the better place for excavation but we must drill here or not at all—so let us be busy.'
With Count Axel's help the drilling machine was set in motion at the base of the nearest column, which was quite near them. Inside the sphere they could not hear the faintest murmur as it bored into the solidified lava and the indicator on a small dial near the door was the only means of knowing when it had completed the first hole. A charge of explosive was inserted down a tube by an automatic loader, with an electric wire attached which could be reeled out as the bathysphere was drawn up, then the drill was set to work upon another boring.
All the time these operations were in progress fish came and went beyond the windows, flitting like ghostly shadows in and out of the bright beam. A sabre-toothed Viper fish snapped its wicked jaws within a few inches of Sally's face, but on touching the fused quartz, whipped off again, startled perhaps by this invisible barrier. The shrimps at this depth were big fellows eight to ten inches in length. They appeared to be bright scarlet with jet black eyes whereas, at about 1,500 feet the McKay had noticed that they were only pale pink and near the surface a transparent white. Seven black jellies came bobbing along in an uneven row and then a large umbrella-like pink one with luminous spots at the base of each of its threadlike tentacles. Nearly every creature seemed to possess its own lighting apparatus, some having a coppery or silvery iridescence over their whole bodies, others luminous teeth, or portholes in their sides; only the Palid Sailfins and Eels showed no illumination. For an hour, that ghostly shadow dance, lit by displays of ever changing coloured fireworks, went on without a second's interruption, then the Doctor reported the first borings to be completed and Nicky asked Oscar, who had taken over the deck end of the telephone, to have the sphere pulled up 300 feet.
As they ascended the McKay noticed that they were not going up quite straight but at an angle and, for a second, he feared that the sphere would be dashed against the solid wall upon their right.
His mouth set tight as he waited for instant oblivion to overwhelm them. He had just time to think grimly that this was the sort of unexpected calamity which he had visualised, when the wall top came into view six feet away and they passed clear above it. The whole episode was over so quickly that the others had failed even to realise the danger and the narrowness of their escape.
The wires connected with the charges in the bore holes had reeled out automatically as they rose and when they halted the Doctor put his hand on the lever to explode them.
'It's no good I'm afraid.' The McKay shook his head. 'We only remained stationary on the bottom because the drill and the claws held us. The ship is drifting to eastward slightly, and as she is not under power they won't be able to tow us back to the place we've mined.'
The Doctor grunted with disappointment. 'I will explode the charges all the same,' he said after a moment. 'We may see the effect perhaps when we descend again even if we cannot collect the debris.'
No faintest sound came to indicate that the explosion had taken place when the Doctor pressed the lever of the detonator but, just after, the bathysphere lifted slightly as the water was forced upwards, then settled till the cable took its weight again with a very gentle jerk. Nicky requested that they should be lowered and six minutes later they came to rest on the bottom.
They turned the bathysphere on its own axis and could not recognise any of the stone masses as those which they had seen before. A faint cloudiness at one point, seen in the extreme end of the searchlight's beam, indicated the probable direction of their previous position, as the explosion would have pulverised some of the stone and lava into fine dust, but they were too far off to glimpse the row of columns.
Further mining operations were obviously useless so it was decided to rise thirty feet and then drift with the ship. For the next twenty-five minutes they moved very slowly to the westward passing through two huge pillars and then across a comparatively open space, at one side of which great blocks and hummocks were vaguely discernable in the distance.
The McKay estimated that they were drifting at about 200 yards an hour and he explained that in addition to the kedge anchors, which Captain Ardow had thrown out, the bathysphere was acting as a super kedge which assisted in slowing up the ship's movement. Even at this low speed their position must have altered at least a mile and a half since the Doctor and Nicky had found the Atlantean remains the previous afternoon—if they had been shifting steadily in one direction. The wind had changed twice however so the probability was that they were still within a mile of the spot over which the ship had been when Count Axel staged his explosion, but it was possible of course that the ruins of the sunken city covered a much greater area.
A large headed rat-tailed macrourid a foot in length and with at least six lights had paused to peer in at the window when, without warning, the sphere suddenly began to rise.
'Oh, what's happening?' cried Camilla in a frightened voice. 'I do pray that there's not another storm approaching. Ask Nicky—ask why they are pulling us up.'