“I’ll bet you would — for one thing,” Ken replied. Feth’s smile disappeared.
“Yes — just one,” he agreed soberly. “But I see no chance of that. It would take a competent medical researcher years, even on Sarr with all his facilities. What hope would we have here?”
“I don’t know, but neither of us is senile,” retorted Ken. “It’ll be a few years yet before I give up hope. Let’s look at that suit you fixed, and the one I wore on Four. They may tell us something of what we’ll have to guard against.” This was the first Feth had heard of the sortie on Mars, and he said so. Ken told of his experience in detail, while the mechanic listened carefully.
“In other words,” he said at the end of the tale, “there was no trouble until you actually touched this stuff you have decided was hydrogen oxide. That means it’s either, a terrifically good conductor, has an enormous specific heat, a large heat of vaporization, or two or three of those in combination. Right?” Ken admitted, with some surprise, that that was right. He had not summed up the matter so concisely in his own mind. Feth went on: “There is at the moment no way of telling whether there is much of that stuff on Three, but the chances are there is at least some. It follows that the principal danger on that planet seems to be encountering deposits of this chemical. I am quite certain that I can insulate a suit so that you will not suffer excessive heat loss by conduction or convection in atmospheric gases, whatever they are.”
Ken did not voice his growing suspicion that Feth had been more than a mechanic in his time. He kept to the vein of the conversation.
“That seems right. I’ve seen the stuff, and it’s certainly easy to recognize, so there should be no difficulty in avoiding it.”
“You’ve seen the solid form, which sublimed in a near vacuum. Three has a respectable atmospheric pressure, and there may be a liquid phase of the compound. If you see any pools of any sort of liquid whatever, I would advise keeping clear of them.”
“Sound enough — only, if the planet is anything like Sarr, there isn’t a chance in a thousand of landing near open liquid.”
“Our troubles seem to spring mostly from the fact that this planet isn’t anything like Sarr,” Feth pointed out dryly. Ken was forced to admit the justice of this statement, and stored away the rapidly growing stock of information about his companion. Enough of Feth’s former reserve had disappeared to make him seem a completely changed person.
The suits were brought into the shop and gone over with extreme care. The one used on Planet Four appeared to have suffered no damage, and they spent most of the time on the other. The examination this time was much more minute than the one Ken had given it on board the Karella, and one or two new discoveries resulted. Besides the bluish deposit Ken had noted on the metal, which he was now able to show contained oxides, there was a looser encrustation in several more protected spots which gave a definite potassium spectrum — one of the few that Ken could readily recognize — and also a distinct odor of carbon bisulfide when heated. That, to the chemist, was completely inexplicable. He was familiar with gaseous compounds of both elements, but was utterly unable to imagine how there could have been precipitated from them anything capable of remaining solid at “normal” temperature.
Naturally, he was unfamiliar with the makeup of earthly planets, and had not seen the fire whose remains had so puzzled Roger Wing. Even the best imaginations have their limits when data are lacking.
The joints had, as Feth expected, shrunk at the seals, and traces of oxides could be found in the insulation. Apparently some native atmosphere had gotten into the suit, either by diffusion or by outside pressure after the sulfur had frozen.
“Do you think that is likely to happen with the packing properly tightened?” Ken asked, when this point had been checked.
“Not unless the internal heaters fail from some other cause, and in that case you won’t care anyway. The over-tightening cut down the fluid circulation in the temperature equalizing shell, so that at first severe local cooling could take place without causing a sufficiently rapid reaction in the main heaters. The local coils weren’t up to the job, and once the fluid had frozen at the joints of course the rest was only a matter of seconds. I suppose we might use something with a lower freezing point than zinc as an equalizing fluid — potassium or sodium would be best from that point of view, but they’re nasty liquids to handle from chemical considerations. Tin or bismuth are all right that way, but their specific heats are much lower than that of zinc. I suspect the best compromise would be selenium.”
“I see you’ve spent a good deal of time thinking this out. What would be wrong with a low specific heat liquid?”
“It would have to be circulated much faster, and I don’t know whether the pumps would handle it — both those metals are a good deal denser than zinc, too. Selenium is still pretty bad in specific heat, but its lower density will help the pumps. The only trouble is getting it. Well, it was just a thought — the zinc should stay liquid if nothing special goes wrong. We can try it on the next test, anyway.”
“Have you thought about how you are going to justify this next trial, when Drai asks how come?”
“Not in detail. He won’t ask. He likes to boast that he doesn’t know any science — then he gloats about hiring brains when he needs them. We’ll simply say that we have found a way around the cause of the first failure — which is certainly true enough.”
“Could we sneak a televisor down on the next test, so we could see what goes on?”
“I don’t see how we could conceal it — any signal we can receive down here can be picked up as well or better in the observatory. I suppose we might say that you had an idea in that line too, and we were testing it out.”
“We could — only perhaps it would be better to separate ideas a little. It wouldn’t help if Drai began to think you were a fool. People too often connect fools and knaves in figures of speech, and it would be a pity to have him thinking along those lines.”
“Thanks — I was hoping you’d keep that point in mind. It doesn’t matter much anyway — I don’t see why we can’t take the Karella out near Three and make the tests from there. That would take only a matter of minutes, and you could make the dive right away if things went well. I know it will be several days before the ship will be wanted — more likely several weeks. They get eight or ten loads of tofacco from the planet during the ‘season’ and several days elapse between each load. Since all the trading is done by torpedo, Lee has a nice idle time of it.”
“That will be better. I still don’t much like free fall, but a few hours of that will certainly be better than days of waiting. Go ahead and put it up to Drai. One other thing — let’s bring more than one suit this time. I was a little worried for a while, there, out on Four.”
“A good point. I’ll check three suits, and then call Drai.” Conversation lapsed, and for the next few hours a remarkable amount of constructive work was accomplished. The three units of armor received an honest preservice check this time, and Feth was no slacker. Pumps, valves, tanks, joints, heating coils — everything was tested, separately and in all combinations.
“A real outfit would spray them with liquid mercury as a final trick,” Feth said as he stepped back from the last suit, “but we don’t have it, ana we don’t have any place to try it, and it wouldn’t check as cold as these are going to have to take anyway. I’ll see what Drai has to say about using the ship — we certainly can’t run three torpedoes at once, and I’d like to be sure all these suits are serviceable before any one of them is worn on Three.” He was putting away his tools as he spoke. That accomplished, he half turned toward the communicator, then appeared to think better of it.