centimeters by a little over a hundred, with rounded edges. At the bottom you could see the cold blue glow of the outside of the tunnel, only pocked by the augers and blotched by the loose castings I hadn't bothered to get out.
'Now what?' Cochenour demanded. His voice was hoarse with excitement-natural enough, I guessed.
'Now we burn our way in.'
I backed my clients as far away as they could get inside the igloo, pressed against the remaining heap of castings. Then I unlimbered the firejets. I'd already hung shear-legs over the shaft. The jets slipped right down on their cable until they were just a few centimeters above the round of the tunnel.
Then I fired them up.
You wouldn't think that anything a human being might do would make anything hotter than Venus does already, but the firejets were something special. In the small space of the igloo the heat
flamed up and around us. Our heatsuit cooling systems were overwhelmed in a moment.
Dorrie gasped, 'Oh! I-I think I'm going to-'
Cochenour grabbed her arm. 'Faint if you want to,' he said fiercely, 'but don't get sick inside your suit. Waithers! How bug does this go on?'
It was as hard for me as it was for them. Practice doesn't get you used to something like standing in front of a blast furnace with the doors off the hinges. 'Maybe a minute,' I gasped. 'Hold on-it's all right.'
It actually took a little more than that, maybe ninety seconds. My suit telltales were shouting overload alarm for more than half of that time. But the suits were built for these temporary overloads. As long as we didn't cook inside them, the suits themselves would survive.
Then we were through. A half-meter circular section of the tunnel roof sagged, fell at one side, and hung there, swaying.
I turned off the jets. We all breathed hard for a couple of minutes, while the Suit coolers gradually caught up with the load.
'Wow,' said Dorotha. 'That was pretty rough.'
In the light that splashed up out of the shaft I could see that Cochenour was frowning. I didn't say anything. I just gave the jets another five-second burn to cut away the rest of the circular section. It fell free to the tunnel floor, with a smack like rock.
Then I turned on my helmet radio.
'There's no pressure differential,' I said.
Cochenour's frown didn't change, nor did he speak.
'That means this one has been breached,' I went on. 'Somebody found it, opened it up-probably cleaned it out, if there ever was anything here-and just didn't report it. Let's go back to the airbody and get cleaned up.'
Dorotha shrieked, 'Audee, what's the matter with you? I want to go down there and see what's inside!'
'Shut up, Dorrie,' Cochenour said bitterly. 'Don't you hear what he's saying? This one's a washout.'
Well, there's always the chance that a breached tunnel might have been opened by some seismological event, not a maze-rat with a cutting torch. If so, there might possibly be something in it worth having anyway. And I didn't have the heart to kill all Dorotha's enthusiasm with one blow.
So we did swing down the cable, one by one, into the Heechee dig. We looked around. It was wholly bare, as most of them are, as far as we could see. That wasn't actually very far. The other thing wrong with a breached tunnel is that you need special equipment to explore it. With the overloads they'd already had, our suits were all right for another few hours but not much more than that.
So we tramped down the tunnel about a kilometer and found bare walls, chopped-off struts on the glowing blue walls that might once have held something-and nothing movable. Not even junk.
Then they were both willing to tramp back and climb up the cable to the airbody. Cochenour made it on his own. So did Dorrie, though I was standing by to help her; she did it all hand over hand, using the stirrups spaced along the cable.
We cleaned up and made ourselves a meal. We had to eat, but Cochenour was not in a mood for his gourmet exhibition. Silently, Dorotha threw tablets into the cooker and we fed gloomily on prefabs.
'Well, that's only the first one,' she said at last, determined to be sunny about it. 'And it's only our second day.'
Cochenour said, 'Shut up, Dorrie. If there's one thing I'm not, it's a good loser.' He was staring at the probe trace, still displayed on the screen. 'Walthers, how many tunnels are unmarked but empty, like this one?'
'How do I know? If they're unmarked, there's no record.'
'Then those traces don't mean anything, do they? We might dig all eight and find every one a dud.'
I nodded. 'We surely might, Boyce.'
He looked at me alertly. 'And?'
'And that's not the worst part of it. At least this trace was a real tunnel. I've taken parties out who would've gone mad with joy to open even a breached tunnel, after a couple of weeks of digging up dikes and intrusions. It's perfectly possible all seven of those others are nothing at all. Don't knock it, Boyce. At least you got some action for your money.'
He brushed that off. 'You picked this spot, Walthers. Did you know what you were doing?'
Did I? The only way to prove that to him would be to find a live one, of course. I could have told him about the months of studying records from the first landings on. I could have mentioned how much trouble I went to, and how many regulations I broke to get a look at the military survey reports, or how far I'd traveled to talk to the Defense crews who'd been on some of the early digs. I might have let him know how hard it had been to locate old Jorolemon Hegramet, now teaching exotic archaeology back in Tennessee; but all I said was, 'The fact that we found one tunnel shows that I know my business. That's all you paid for. It's up to you whether we keep looking or not.'
He gazed at his thumbnail, considering.
