“I fear not, sir,” the silver said, politely. “Had this possibility been anticipated, such equipment would doubtless have been provided, but it was not. If you were to attempt to leave the craft in the suitskin you are wearing you would certainly drown, and even if you were able to contrive some kind of breathing apparatus you would die of hypothermia in less than an hour.”

“So we sit tight and wait to be rescued?” I said, hopefully.

“I am doing everything within my power to summon help,” the silver assured me. If my recent conversations with Eve had taught me nothing else, they had taught me to be more sensitive than before to the possibility that certain things were being deliberately left unsaid.

“And you willbe able to summon help,” I said, as my heart sank to further depths than the snowmobile, “won’t you?”

“I am not presently aware of any craft that is in a position to attempt a rescue,” the silver admitted. Silvers are programmed to believe that honesty is the best policy, if pressed.

I was astonished by my own calmness, which contrasted very strongly with the panic I had felt when I realized that the Genesishad turned turtle. Being so much older and wiser than I had been way back then, I was marvelously untroubled, at least for the moment, by the fact of my helplessness.

“How long will the air last?” I asked the navigator.

“I believe that I could sustain a breathable atmosphere for at least twelve, and perhaps as long as twenty hours,” it reported, dutifully. “If you will be so kind as to restrict your movements to a minimum, that would be of considerable assistance to me. You are presumably a better judge than I of the ability of your internal nanotechnology to sustain you once you fall unconscious.” The machine was presuming too much; I had no idea how long my IT could keep me alive once the oxygen level dropped below the critical threshold.

“Why did you say I believe that I could sustaininstead of I can sustain?”I wanted to know.

“Unfortunately,” the silver admitted, “I am not certain that I can maintain the internal temperature of the cabin at a life-sustaining level for more than ten hours. Nor can I be sure that the hull will withstand the pressure presently being exerted upon it for as long as that. I apologize for my uncertainty in these respects.”

“Taking ten hours as a hopeful approximation,” I said, effortlessly matching the machine’s oddly pedantic tone, “what would you say our chances are of being rescued within that time?”

“I’m afraid that it’s impossible to offer a probability figure, sir. There are too many unknown variables, even if I accept ten hours as the best estimate of the time available. Unfortunately, I am not aware of the presence in our vicinity of any submarine craft capable of taking aboard a human passenger, although it is conceivable that a human diver might be able to transport a suitskin capable of sustaining you. In either case, though, the fact that this craft is not equipped with an airlock would make the problem of getting you into the suitskin rather vexatious, even if I were actually able to open the door.”

The last sentence seemed particularly ominous. It implied, in fact, that even if an unexpected stroke of luck were to make the machine’s worst fears redundant, I would stillbe well and truly doomed.

“If I were to suggest that my chances of surviving this were about fifty-fifty,” I said, carefully, “would that seem optimistic or pessimistic to you?”

“I’m afraid I’d have to call that optimistic, sir,” the silver confessed.

“How about one in a thousand?” I asked, hoping to be told that there was no need to plumb such abysmal depths of improbability.

The silver’s hesitation spoke volumes. “There are, I fear, too many imponderables to make such a fine-tuned calculation,” it informed me, choosing its words carefully. “Much depends on the precise proximity and exact design of the nearest submarine. I fear that any craft attempting a rescue would probably be required to take aboard the entire snowmobile if you were to have any chance of surviving the transfer process. I am not aware of the availability of any such craft within a thousand miles, and even if one were available, it could only be launched if my may day has actually been received.”

“What do you mean, if?” I objected, sharply. “Your transmitter’s working, isn’t it?”

“According to my diagnostic program,” the silver replied, with what seemed to me to be undue caution, “my broadcasting capability has not been impaired.”

The unspoken butrang more clearly in my consciousness than if it had been voiced.

“So what hasbeen impaired?” I demanded.

“I fear, sir, that I am not able to receive any kind of incoming message. The fact that I have not received an acknowledgment obliges me to retain some doubt as to whether my alarm signal has been picked up—but far the greater probability is that it hasbeen heard and that it is the failure of my own equipment that prevents me from detecting a response. I apologize for the inadequacy of my equipment, which was not designed with our present environment in mind. It has sustained a certain amount of damage as a result of pressure damage to my outer tegument and a small leak.”

“Howsmall?” I demanded, trying hard not to let the shock of the revelation turn into stark terror.

“It is sealed now,” the machine assured me. “All being well, the seal should hold for between eighteen and twenty hours, although I cannot be absolutely sure of that.”

“What you’re trying to tell me,” I eventually said, deciding that a summary recap wouldn’t do any harm, “is that you’re pretty sure that your mayday is going out, but that we won’t actually know whether help is at hand unless and until it actually arrives—although you have no reason to suppose that any submarine capable of saving my life is capable of reaching us before we suffer enough further damage to kill me.”

“Very succinctly put, sir,” the silver said. It wasn’t being sarcastic.

“But you mightbe wrong,” I said, hopefully. “You don’t knowof any submarine capable of attempting a rescue, but that judgment’s based entirely on information you already had when we set out. Because you can only transmit and not receive, you can’t update your status report.”

“The fact that I am not aware of the proximity of a submarine capable of taking us aboard,” the silver confirmed, carefully refusing to overstate the case, “does not necessarilymean that no such vessel can get to us in time to render assistance.”

“However,” I went on, doggedly, “everything you do know about the deployment of suitable submarines suggests the odds against us are far worse than evens and might well be as bad as a thousand to one. Barring a miracle, in fact, we’re as good as dead.”

Even a silver programmed for honesty wasn’t going to admit that. “There are too many imponderables to allow me to make any accurate assessment of probability, sir,” it said, dutifully, “but it is never a good idea, under any circumstances, to give up hope.”

“Is there anything useful we can actually do?”I asked.

“To the best of my knowledge, sir,” the AI navigator informed me, “the course of action that gives us our best, admittedly slender, chance of surviving is to remain as still as possible while continuing to send out a request for urgent assistance. The world has many resources of which I know nothing, and we may be sure that as soon as our distress call is received, always provided that it isreceived, the people on the surface will do everything in their power to get help to us. We must put our trust in human ingenuity.”

I was quiet for a little while then, while I busied myself exploring my feelings, which turned out to be more than a little confused.