“What’s that?” He looked at me narrowly, suspiciously. “Why?”
“Were you thinking of leaving it unflooded?” I asked incredulously. “This entrance chamber is usually flooded the minute you start descending — and that’s normally surface level, not a hundred and thirty feet down as you are here. Sure, sure, I know it looks solid, it might even hold at double this depth, I don’t know. But what I do know is that it is completely surrounded by your gasoline buoyancy tanks, about eight thousand gallons of it, and those are open to the sea at the bottom. The pressure inside those tanks corresponds exactly to the sea pressure outside — which is why only the thinnest sheet metal is required to hold the gasoline. But with only air inside your entrance chamber you’re going to have at least two hundred pounds to the square inch pressing on the outside of this entrance chamber. And it won’t stand that. It’ll burst inwards, your gasoline will escape, your positive buoyancy will be gone for ever and there you are, four hundred and eighty feet below the surface of the sea. And there you would remain until the end of time.”
It was hard to be positive in that thinly-lit gloom, but I could have sworn that the colour had drained from Vyland’s face.
“Bryson never told me this.” Vyland’s voice was a vicious whisper and there was a shake in it.
“Bryson? Your engineering friend?” There was no answer, so I went on: “No, I don’t suppose he would. He was no friend, was he, Vyland: he had a gun in his back, didn’t he, and he knew that when his usefulness was over someone was going to pull the trigger of that gun? Why the hell should he tell you?” I looked away from him and shouldered the bridge megger again. “No need for anyone to come down with me — it’ll only make me nervous.”
“Think I’m going to let you go down there on your own?” he asked coldly. “To get up to your tricks?”
“Don’t be stupid,” I said wearily. “I could stand there in front of an electrical switchboard or fuse-box and sabotage the bathyscaphe so that it would never move again, and neither you nor your friends would ever know anything about it. It’s in my own interests to get this machine going and have the whole thing over as soon as possible. The quicker the better for me.” I glanced at my watch. “Twenty to eleven. It’ll take me three hours to find out what’s wrong. At least. I’ll have a break at two. I’ll knock on the hatch so that you can let me out.”
“No need.” Vyland wasn’t happy, but as long as he couldn’t put his finger on any possibility of treachery he wasn’t going to deny me — he wasn’t in any position to. “There’s a microphone in the cabin, with its extension cable wound round a drum on the outside and a lead through a gland m the side of the leg that’s carried up to that room where we were. There’s a button call-up. Let us know when you’re ready.”
I nodded and started down the rungs welded into the side of the cylinder, unscrewed the upper hatch of the bathyscaphe’s flooding and entrance chamber, managed to wriggle down past it — the downward projecting cylinder which encompassed the top of the entrance chamber was only a few inches wider and didn’t give enough room to open the hatch fully — -felt for the rungs below, pulled down the hatch, clamped it shut and then worked my way down the constricting narrowness of that chamber to the cabin below. The last few feet involved an almost right-angle bend, but I managed to ease myself and the megger round it. I opened the heavy steel door to the cabin, wriggled through the tiny entrance, then closed and locked the door behind me.
Nothing had changed, it was as I had remembered it. The cabin was considerably bigger than that of the earlier F.R.N.S. from which it had been developed, and slightly oval in shape instead of round: but what was lost in structural power was more than compensated for in the scope and ease of movement inside, and as it was only intended for salvage operations up to about 2,500 feet, the relative loss in strength was unimportant. There were three windows, one set in the floor, cone-shaped inwards as was the entrance door, so that sea pressure only tightened them in their seats: they looked fragile, those windows, but I knew that the specially constructed Plexiglas in the largest of them — and that was no more than a foot in its external diameter — could take a pressure of 250 tons without fracturing, many times the strain’ it would ever be required to withstand in the depths in which that bathyscaphe would operate.
The cabin itself was a masterpiece of design. One wall — if approximately one-sixth on the surface area of the inside of a sphere could be called a wall — was covered with instruments, dial, fuse-boxes, switchboards and a variety of scientific equipment which we would not be called upon to use: set to one side were the controls for engine starting, engine speed, advance and reverse, for the searchlights, remote-controlled grabs, the dangling guide-rope which could hold the bathyscaphe stable near the bottom by resting part of its length on the sea-bed and so relieving the scaphe of that tiny percentage of weight which was sufficient to hold it in perfect equilibrium; and, finally, there were the fine adjustments for the device for absorbing exhaled carbon dioxide and regenerating oxygen.
One control there was that I hadn’t seen before, and it puzzled me for some time. It was a rheostat with advance and retard positions graded on either side of the central knob and below this was the brass legend “Tow-rope control.” I had no idea what this could be for, but after a couple of minutes I could make a pretty sure guess. Vyland — or, rather, Bryson on Vyland’s orders — must have fitted a power-operated drum to the top, and almost certainly the rear, of the bathyscaphe, the wire of which would have been attached, before the leg had been lowered into the water, to some heavy bolt or ring secured near the base of the leg. The idea, I now saw, was not that they could thereby haul the bathyscaphe back to the rig if anything went wrong — it would have required many more times the power that was available in the bathyscaphe’s engines to haul that big machine along the ocean bed — but purely to overcome the very tricky navigational problem of finding their way back to the leg. I switched on a searchlight, adjusted the beam and stared down through the window at my feet. The deep circular ring in the ocean floor where the leg had originally been bedded was still there, a trench over a foot in depth: with that to guide, re-engaging the top of the entrance chamber in the cylinder inside the leg shouldn’t be too difficult.
At least I understood now why Vyland hadn’t objected too strongly to my being left by myself inside the scaphe, by flooding the entrance chamber and rocking the scaphe to and fro. If and when I got the engines started, I might easily have managed to tear clear of the rubber seal and sail the bathyscaphe away to freedom and safety: but I wouldn’t get very far with a heavy cable attaching me to the leg of the X 13. Vyland might be a phoney in the ways of dress, mannerisms and speech, but that didn’t alter the fact that he was a very smart boy indeed.
Apart from the instruments on that one wall, the rest of the cabin was practically bare except for three small canvas seats that hinged on the outer wall and a rack where there was stored a variety of cameras and photo-flood equipment.
My initial comprehensive look round the interior didn’t take long. The first thing that called for attention was the control box of the hand microphone by one of the canvas seats. Vyland was just the sort of person who would want to check whether I really was working, and I wouldn’t have put it past him to change over wires in the control box so that when the switch was in the off position the microphone would be continuously live and so let him know that I was at least working, even if he didn’t know what kind of work it was. But I’d misjudged or over-rated him, the wiring was as it should have been.
In the next five minutes or so I tested every item of equipment inside that cabin except the engine controls — should I have been able to start them up anyone still waiting on the bottom floor of that leg would have been sure to feel the vibration.