The hopper crews promptly did something at the nozzle of the bellows each was tending; and as they did so, a roaring sheet of flame spread downwind from the Bree to envelop both of the fighters. The ship’s crew were already sheltered behind their tarpaulins, even the “gunners” being protected by flaps of fabric that formed part of their weapons; but the vegetation that sprouted through the snow was neither tall nor dense enough to shelter the fighters. Lackland, using words that he had never taught Barlennan, hurled the tank backward out of the flame cloud with a prayer for the quartz in his portholes. His adversary, though evidently as anxious to dodge, seemed to lack the necessary control. It lurched first one way, then the other, seeking escape. The flame died out in seconds, leaving a cloud of dense white smoke which gleamed in the tank’s running lights; but either the brief fire had been sufficient or the smoke was equally deadly, for the monster’s disorganization grew steadily worse. Its aimless steps grew shorter and feebler as the legs gradually lost the power to support its vast bulk, and presently it stumbled and rolled on-one side. The legs kicked frantically for a time, while the long neck alternately retracted and stretched to full length, lashing the fanged head frantically through the air and against the ground. By sunrise the only remaining motion, was an occasional — twitch of head or leg; within a minute or two thereafter all activity of the giant creature ceased. The crew of the Bree had already swarmed overboard and across the dark patch where the snow had boiled from the ground, bent on acquiring meat. The deadly white cloud was farther downwind now, and gradually settling. Lackland was surprised to note traces of black dust on the snow where the cloud had passed.
“Barl, what on Earth — or rather, on Mesklin — was the stuff you used for that fire cloud? And didn’t it occur to you that it might crack the windows in this tank?” The captain, who had remained on the ship and was near one of his radios, answered promptly.
“I’m sorry, Charles; I didn’t know what your windows are made of, and never thought of our flame cloud as a danger to your great machine. I will be more careful next time. The fuel is simply a dust which we obtain from certain plants-it is found as fairly large crystals, which we have to pulverize very carefully and away from all light.” Lackland nodded slowly, digesting this information. His chemical knowledge was slight, but it was sufficient to make a good guess at the fuel’s nature. Ignited by, light — burned in hydrogen with a white cloud — black specks on the snow — it could, as far as he knew, be only one thing. Chlorine is solid at Mesklin’s temperature; it combines violently with hydrogen, and hydrogen chloride is white when in fine powder form; methane snow boiled from the ground would also give up its hydrogen to the voracious element and leave carbon. Interesting plant life this world sported! He must make another report to Toorey — or perhaps he had better save this tidbit in case he annoyed Rosten again.
“I am very sorry I endangered your tank.” Barlennan still seemed to feel apologetic. “Perhaps we had better let you deal with such creatures with your gun; or perhaps you could teach us to use it. Is it, like the radios, especially built to work on Mesklin?” The captain wondered if he had gone too far with this suggestion, but decided it had been worth it. He could neither see nor interpret Lackland’s answering smile.
“No, the gun was not remade or changed for this world, Barl. It works fairly well here, but I’m afraid it would be pretty useless in your country.” He picked up a slide rule, and added one more sentence after employing it for a moment. “The farthest this thing could possibly shoot at your pole would be just about one hundred fifty feet.”
Barlennan, disappointed, said nothing further. Several days were spent in butchering the dead monster. Lackland salvaged the skull as a further protection from Rosten’s ire, and the cavalcade resumed its journey.
Mile after mile, day after day, the tank and its tow inched onward. Still they sighted occasional cities of the rock-rollers; two or three times they picked up food for Lackland which had been left in their path by the rocket; quite frequently they encountered large animals, some like the one Barlennan’s fire had slain, others very different in size and build. Twice specimens of giant herbivores were netted and killed by the crew to furnish meat, much to Lackland’s admiration. The discrepancy in size was far greater than that existing between Earthly elephants and the African pygmies who sometimes hunted them.
The country grew hillier as they progressed, and with the rising ground the river, Which they had followed intermittently for hundreds of miles, shrank and split into numerous smaller streams. Two of ‘these tributaries had been rather difficult to cross, requiring that the Bree be unlashed from the sled and floated across at the end of a towrope while tank and sled drove below the surface on the river bed. Now, however, the streams had become so narrow that the sled actually bridged them and no such delays occurred.
At long last, fully twelve hundred miles from where the Bree had wintered and some three hundred south of the equator, with Lackland bowing under an additional half gravity, the streams began to bear definitely in the general direction of their travel. Both Lackland and Barlennan let several days pass before mentioning it, wishing to be sure, but at last there was no more doubt that they were in the watershed leading to the eastern ocean. Morale, which had never been low, nevertheless improved noticeably; and several sailors could now always be found on the tank’s roof hoping for the first glimpse of the sea as they reached each hilltop. Even Lackland, tired sometimes to the point of nausea, brightened up; and as his relief was the greater, so proportionately greater was his shock and dismay when they came, with practically no warning, to the edge of an escarpment; an almost sheer drop of over sixty feet, stretching as far as the eye could see at right angles to their course.
IX: OVER THE EDGE
For long moments nothing was said. Both Lackland and Barlennan, who had worked so carefully over the photographs from which the map of their journey had been prepared, were far too astonished to speak. The crew, though by no means devoid of initiative, decided collectively and at the first glance to leave this problem to their captain and his alien friend.
“How could it have been there?” Barlennan was first to speak. “I can see it’s not high, compared to the vessel from which your pictures were taken, but should it not have cast a shadow far across the country below, in the minutes before sunset?”
“It should, Barl, and I can think of only one reason it escaped us. Each picture, you recall, covered many square miles; one alone would include all the land we can see from here, and much more. The picture that does cover this area must have been made between sunrise and noon, when there would have been no shadow.”
“Then this cliff does not extend past the boundary of that one picture?”
“Possibly; or, just as possibly, it chanced that two or three adjacent shots were all made in the morning — I don’t know just what course ‘the photo rocket flew. If, as I should imagine, it went east and west, it wouldn’t be too great a coincidence for it to pass the cliff several times running at about the same time of day.
“Still, there’s little point in going through that question. The real problem, since the cliff obviously does exist, is how to continue our journey.” That question produced another silence, which lasted for some time. It was broken, to the surprise of at least two people, by the first mate.