four starts in as many different directions and twenty minutes of time showed fairly conclusively that the line of vegetation which had given rise to the "street" theory was growing along a straight crack, apparently a fairly ordinary joint, in the limestone. while several more holes would have to be drilled to prove it, even mitsuitei was willing to admit that in all probability the remaining lines would be found to be over similar cracks.
"you must admit, though, that the regularity of this joint pattern is pretty unusual," the archaeologist said at length.
"it's far from being unknown," lampert replied. "i got my first large taste of it in my student days back on earth. fly over the mesa country in southwestern north america sometime. most of the joints there are invisible from a distance, of course; but at the edge of a butte where weathering is most prominent the blocks have frequently started to separate, and the thing looks as though it had been put together from outsize bricks."
"hmph. seem to remember something of the sort myself, now that you mention it. i did some digging in that area, too. i shouldn't have connected that sort of country with what we have here, though."
"different meat; same skeleton," replied lampert.
"but how about this volcanic ash, or mud, or whatever it is, which at least fills the joints we saw in the cliff? that's not so usual, is it?"
"not in my experience. but granting the joints and the volcanoes, there's nothing really surprising about it. incidentally, we don't know that this crack we're standing on has the same filling. we'd better bore down again to make sure. at least we may get some idea of the date of the volcanic action compared to that of the orogeny that tilted the block where we're camped. if there's tuff down here too, it will substantiate the idea that the vulcanism is the older."
"why? couldn't ash have settled down here as well as up there at substantially the same time?"
"it could. but i'd bet a fairly respectable sum that the tuff we saw in the canyon was from a mud flow, not a fall of airborne ash. that could hardly have reached the top of the cliffs—actually, the opposite slope of the mountains, where sulewayo is working—and this area simultaneously."
"maybe from different eruptions? i get the impression that this world has a slight tendency to produce volcanic fields rather than individual cones or flows."
"might be. chemistry will probably settle that question." during the latter part of this discussion lampert had directed the mole once more downwards, and every half meter of travel another core was added to the collection. at six and a half meters below the soil the first solid specimen arrived; the others had been held together only by roots. this one, however, caused the two scientists to look at each other. lampert nodded slowly, with a smile. mitsuitei gave a shrug, and let an expression of resignation play over his usually impassive features.
the core was tuff, apparently identical with that in the cliffs to the east. it even contained fossils.
"i guess this whole dig might as well be taken over by the paleontology department," lampert commented finally. "i suppose they'll at least want to compare fossils in the tilted and level strata."
"i suppose so." mitsuitei was turning the little cylinder over and over in his hand. "tell me, rob, what's this little speck of green?"
"copper salts of one sort or another, i suppose." lampert was not greatly interested. "a lot of secondary minerals form in and under volcanic detritus. on this world, carbonates like malachite should form quite readily."
"why should it form in a regular thread like this?"
"you mean a vein? hard to tell precisely. varying rates of water seepage, varying degrees of oxygen or carbon dioxide penetration, varying degrees of compactness in the rock where the stuff is formed—"
"i don't mean a vein. this is in a cylindrical body going right through the core from one side to the other, as though there had been a copper wire there originally which had been attacked by soil acids."
"let's see. you're right. it's hardly an ordinary vein, though your suggestion seems a trifle far fetched. the paleontologists can probably furnish an idea. maybe a vine or even a worm buried in the mud flow acted as the precipitating agent for copper salts in the subsequent seepage—i've seen beautiful fossils of pyrite which had been formed that way."
"but this shows no trace of structure, except for its exterior shape."
"isn't a really well preserved structure the exception rather than the rule in fossils?"
"i suppose so. still, i'd like to know just how far, and which way, this green thread goes. i'd also like to know whether there are dilute copper deposits spread through this rock, which could be concentrated in the way you suggest."
"the first could be learned by taking enough cores. the other would call for some very careful analysis of samples which had been selected with a very sedulous eye kept on the stratigraphy. you know that; you must have done that sort of thing looking for carbon-fourteen samples, at times."
"yes, i see that. could you make such analyses here?"
"no, except for the mere presence of copper. the cores would have to go back to a well equipped lab. still, if you want to get them, it's all right with me. problems were made to be solved. i'll admit this one doesn't seem very exciting to me, but i can use your data after you finish for work of my own. you should wind up with material for a pretty complete geochemical picture of this neighborhood. shall i get the cores for you?"
"yes, please."
"silly question. all right." the mole was drawn up a short distance, and sent questing downward once more at an angle to the original shaft, branching off a short distance above the level from which the copper deposit had come. again and again the process was repeated, each time at a slightly different bearing from the central hole; and mitsuitei examined each core for traces of green. at last he found it, piercing the little cylinder of rock as the other had done; and then, at his suggestion, lampert reset the mole to get a sample in the opposite direction from the one which had furnished the new specimen.
this also checked positive; and four more samples, taken along the same line at various distances, all did the same.
apparently the line of green extended for some distance, about parallel both to the surface of the ground and the trend of the joint in which it was buried. mitsuitei was radiant.
"i'm going down to that level if i have to come back with an expedition of my own! if that's a fossil worm, it's worth getting the whole length anyway—but i don't believe it is. i—"
"that will take a lot of time, you know," lampert pointed out mildly.
"certainly i know! even if i use your fast excavator down to the tuff level, i'll have to do detail work from then on. what of it?"
"well, the others may have jobs they want to do—"
"then they can do them! what are we here for, anyway? i thought it was to investigate the past of this planet! ndomi and hans are doing that their own way right now. why can't i? i'm an archaeologist, and i came along to do any archaeological work that presented itself to do; this is the only thing of the sort anyone's seen so far. i know what you're thinking. maybe you're partly right. i certainly won't bet any money that this thread of green is a fossil telephone wire; but it's as likely to be that as anything else you've suggested, and i'm going down to that level and sift the whole volume. hans and ndomi can have any fossils i find if that will make you happier—and if one of them says he has no use for fossils he didn't dig himself, i'll make him eat his words. i can identify, locate and report on anything that turns up in a rock as well as any of those jigsaw-puzzle people; and i can do it in mud, too, which is more than any of them could manage."
"don't get hot under the collar. if you can help it on this planet. you sound as though one of the boys had been giving you a lecture on the importance of knowing what strata a given series of specimens represent."
"not one of our boys—they have a little more sense. but there was a young paleontologist when i was covering the antares worlds whose memory still makes my blood pressure go up. never mind me; that's not important. but i want to make this dig."
"it will tie up machines, however freely we can spare time," lampert said slowly. "i'll tell you: how about this? we spend the rest of the day getting cores from other points along these cracks. for one thing, we ought to know more about the structure of the hill, and for another, we might find more of your 'wires.' after all, the chance of our hitting the only one around is pretty remote. i can't quite see a single dropped piece of copper wire showing up in the first two days of a project like this."
"i neither said nor implied that this should be the only piece. i don't doubt for a moment that there are others, whether they are wires or worms."
"sorry. well, we take these cores back to camp this evening, together with any others we find of the same sort, and let hans and ndomi look them over. if they don't turn out to be something that the boys recognize and can classify right off the bat, we come back tomorrow with all the digging machinery you want, and dig until you either find all you want, satisfy yourself that there's nothing here or find something which obviously requires more specialized attention than we can give it. all right?"
"nothing could be fairer. let's go!"
the discussion in camp that evening was animated beyond anything the guide had heard. his original estimate of these men as relatively quiet specimens underwent a sharp revision. mitsuitei's report of the day's activity at his site had, it is true, been delivered quite calmly; but from then on matters grew progressively livelier. this was not caused by opposition to the archaeologist's plans. the others were all in favor of remaining, for their own reasons. however, the question of just what was likely to be found gave rise to much rather barbed comment on sulewayo's part. "i don't see how you can expect to find any trace of civilized work here," he said flatly at one point. "the animal and plant life of this planet is at a stage of evolution corresponding to something like earth's pennsylvanian age, when the amphibians were the highest known forms of life. i'm not saying that there couldn't be such a thing as an intelligent amphibian. but i do say that the normal set of evolutionary forces which, on both earth and viridis, produced creatures of the amphibian pattern could have done that or produced an intelligent fish; not both. if the latter ever evolved, it failed; for the amphibians—pardon me, amphibids—are here. to get an intelligent amphibid on this world will—or would, if the sun were to last long enough—require another orogenic period with the accompanying climatic changes. then you'd stand a considerably higher chance of getting reptiles instead, if the comparative work done on over four hundred planets carries any meaning."
"i don't doubt the value of the work at all. you are very probably correct. it did not occur to me to expect remains of intelligent amphibians. i saw no reason to pre-suppose that anything in the way of artifacts which i might find would necessarily be native to this planet."
"you think there were other visitors from outside the beta librae system?"
"the possibility certainly exists. here we are."
"but for pete's sake! do you really expect that they stayed long enough to build a city, or do you think you have the remains of a camp like ours, or what?"
"i don't think anything. it has been suggested that such people did come, and stayed long enough to—"
"and you think you've found them."
"i think nothing, except that i have found, with rob's help, something which neither his professional knowledge, nor mine, nor even yours, is able to explain; and i think an explanation is desirable. i hope you won't consider me discourteous for pointing out that each time you have tried to accuse me of jumping to conclusions, you have been able to do so only by jumping to some yourself. i might further add that the suggestion that this planet had been stocked with its present supply of life types by visitors from space was advanced by a paleontologist, not by one of my colleagues. i gather he could not understand how life could evolve to the state it shows in the thirty-odd million years that the planet seems to have been solid. i neither support nor deride the idea; i simply want to gather data, in an attempt to explain a much simpler question—why are narrow threads of copper compounds to be found every few feet in the volcanic tuff filling the joints in a certain limestone hill, and why are those threads always nearly horizontal? you and hans say they are not organic fossils, and i accept your conclusion. rob says that there is no copper in that rock, detectable with his equipment, except within a few millimeters of the green threads. i say nothing except that i have never seen such a thing before. under the circumstances, i fail to understand where you get the idea that i think there is a city built by the people who stocked this world thirty million years ago buried under that hill. i know i said 'city' when i first saw it, and i still think i was justified in the opinion; i have now seen evidence which causes me to admit that the vegetation pattern was not caused by artificial structures, and i dismiss the original hypothesis. i still want to dig there, and in accordance with rob's agreement i am going to dig there, with the assistance of anyone who chooses to help. i know you want to go back to your set of leg bones in the cliff, and have no objection to your doing so. even i can now see, on the basis of your description, that you are uncovering the fossil of a land animal; and i agree that it is of great importance to get it out intact, if possible. but if i can see the importance and even the nature of your work, why can't you do the same for mine?" the little man was leaning forward and staring intensely into sulewayo's face by the time he finished this harangue, and ndomi once more felt a trifle ashamed of himself. lampert, however, saved him the need of formulating an apology.
"i'm sure ndomi didn't mean to ridicule your work in any way, take," he said. "we all realize perfectly that an underground phenomenon which cannot be explained at sight either by geology, paleontology or archaeology is something which requires investigation. i imagine that the best plan will be for string and me to go with you tomorrow, while the others continue their stone-cutting. hans, just how far along are you, anyway?"
the older paleontologist thought for a moment.
"we don't really know," he said at last. "of course, we aren't trying to get the individual bones completely free of the matrix; that will take somebody months or years. we're uncovering just enough to determine the extent of the specimen, so we can take it all out in one block—or more, of course, if it's too big. so far we can only guess at how big it is. we've uncovered with certainty two feet, and gone about half a meter along one of the attached legs. they seem to be extending straight back into the cliff, so in effect we're cutting a tunnel beside the thing. assuming it had two main leg sections, as most of the present animals on both earth and viridis appear to have, we're about halfway between knee and hip joint. of course, it might turn out to be the viridian equivalent of a horse or chicken. in that case, we're about half way between ankle and knee. we certainly have several feet yet to penetrate before we can outline the whole block, assuming that the specimen is essentially complete. several days, i would guess."
"can you use any sort of power apparatus for any of your cuts?"
"i don't like to, on general principles, but—yes, we could, with actually very little risk. if you have some sort of rock saw whose cutting part can get fine control, i'd be willing to use it for parts of the tunnel away from the actual specimen."
"i have. we'll take you up there first thing in the morning, and i'll go down with you and show you how to use it before going on with take and string."
"who holds the 'copter in place while you climb down the ladder, give your lesson and come back?" asked the guide.
"hmph. i forgot about that. all right, i'll break out the machinery and give the lesson right now." he got up and strode to the helicopter. mclaughlin covered him from the fence to the aircraft, but nothing dangerous appeared. the geophysicist disappeared inside, and returned a moment later with a compact metal case under his arm. the guide holstered his weapon as the gate in the fence closed once more....
actually, the felodon was miles downstream. it had spent the day in its chosen lair, apparently indifferent to the doings of the men a few hundred yards away. with the coming of darkness—real darkness this time, for the rain clouds cut off both the moonlight and the night glow from the upper atmosphere—it had emerged, hunted, killed and fed as before, apparently unhampered by the lack of light. by midnight it was back in the same lair, paunch distended, as close to sleep as its coldblooded kind ever came.