---

Sargon of Akkad was holding court in all of his splendor in the Mesopotamia area, which he thought to be the center of the Universe. The stars to him were but holes in a black bowl which he called the sky. They were beautiful then, as they are now, but he thought that they were put there for his edification only; for was he not the ruler of Akkadia?

After Sargon of Akkad, there would come sixty centuries of climbing before men reached the stars and found not only that there had been men upon them, but that a civilization on Mars had reached its peak four thousand years before Christ and was now but a memory and a wealth of pictographs that adorned the semipreserved Temples of Canalopsis.

And sixty centuries after, the men of Terra wondered about the ideographs and solved them sufficiently to piece together the wonders of the long-dead Martian Civilization.

Sargon of Akkad did not know that the stars that he beheld carried on them wonders his mind would not, could not, accept.

Altas, the Martian, smiled tolerantly at his son. The young man boasted on until Altas said: "So you have memorized the contents of my manual? Good, Than, for I am growing old and I would be pleased to have my son fill my shoes. Come into the workshop that I may pass upon your proficiency."

Altas led Than to the laboratory that stood at the foot of the great tower of steel; Altas removed from a cabinet a replacement element from the great beam above their heads, and said: "Than, show me how to hook this up!"

Than's eyes glowed. From other cabinets he took small auxiliary parts. From hooks upon the wall, Than took lengths of wire. Working with a brilliant deftness that was his heritage as a Martian, Than spent an hour attaching the complicated circuits. After he was finished, Than stepped back and said: "There—and believe it or not, this is the first time you have permitted me to work with one of the beam elements."

"You have done well," said Altas with that same cryptic smile. "But now we shall see. The main question is: Does it work?"

"Naturally," said Than in youthful pride. "Is it not hooked up exactly as your manual says? It will work."

"We shall see," repeated Altas. "We shall see."

---

Barney Carroll and James Baler cut through the thin air of Mars in a driver-wing flier at a terrific rate of speed. It was the only kind of flier that would work on Mars with any degree of safety since it depended upon the support of its drivers rather than the wing surface. They were hitting it up at almost a thousand miles per hour on their way from Canalopsis to Lincoln Head; their trip would take an hour and a half.

As they passed over the red sand of Mars, endlessly it seemed, a glint of metal caught Barney's eye, and he shouted.

"What's the matter, Barney?" asked Jim.

"Roll her over and run back a mile or so," said Barney. "I saw something down there that didn't belong in this desert."

Jim snapped the plane around in a sharp loop that nearly took their heads off, and they ran back along their course.

"Yop," called Barney, "there she is!"

"What?"

"See that glint of shiny metal? That doesn't belong in this mess of erosion. Might be a crash."

"Hold tight," laughed Jim. "We're going down."

They did. Jim's piloting had all of the aspects of a daredevil racing pilot's, and Barney was used to it. Jim snapped the nose of the little flier down and they power-dived to within a few yards of the sand before he set the plane on its tail and skidded flatwise to kill speed. He leveled off, and the flier came screaming in for a perfect landing not many feet from the glinting object.

---

---

"This is no crash," said Baler. "This looks like the remains of an air-lane beacon of some sort."

"Does it? Not like any I've ever seen. It reminds me more of some of the gadgets they find here and there—the remnants of the Ancients. They used to build junk like this."

"Hook up the sand-blower," suggested Jim Baler. "We'll clear some of this rubble away and see what she really looks like. Can't see much more than what looks like a high-powered searchlight."

Barney hauled equipment out of the flier and hitched it to a small motor in the plane. The blower created a small storm for an hour or so, its blast directed by suit-clad Barney Carroll. Working with experience gained in uncovering the remains of a dozen dead and buried cities, Barney cleared the shifting sand from the remains of the tower.

The head was there, preserved by the dry sand. Thirty feet below the platform, the slender tower was broken off. No delving could find the lower portion.

"This is quite a find," said Jim. "Looks like some of the carvings on the Temple of Science at Canalopsis—that little house on the top of the spire with the three-foot runway around it; then this dingbat perched on top of the roof. Never did figure out what it was for."

"We don't know whether the Martians' eyes responded as ours do," suggested Barney. "This might be a searchlight that puts out with Martian visible spectrum. If they saw with infrared, they wouldn't be using Terran fluorescent lighting. If they saw with long heat frequencies, they wouldn't waste power with even a tungsten filament light, but would have invented something that cooked its most energy in the visible spectrum, just as we have in the last couple of hundred years."

"That's just a guess, of course."

"Naturally," said Barney. "Here, I've got the door cracked. Let's be the first people in this place for six thousand years Terran. Take it easy, this floor is at an angle of thirty degrees."

"I won't slide. G'wan in. I'm your shadow."

---

They entered the thirty-foot circular room and snapped on their torches. There was a bench that ran almost around the entire room. It was empty save for a few scraps of metal and a Martian book of several hundred metal pages.

"Nuts," said Barney, "we would have to find a thing like this but empty. That's our luck. What's the book, Jim?"

"Some sort of text, I'd say. Full of diagrams and what seems to be mathematics. Hard to tell, of course, but we've established the fact that mathematics is universal, though the characters can not possibly be."

"Any chance of deciphering it?" asked Barney.

"Let's get back in the flier and try. I'm in no particular hurry."

"Nor am I. I don't care whether we get to Lincoln Head tonight or the middle of next week."

"Now let's see that volume of diagrams," he said as soon as they were established in the flier.

Jim passed the book over, and Barney opened the book to the first page. "If we never find anything else," he said, "this will make us famous. I am now holding the first complete volume of Martian literature that anyone has ever seen. The darned thing is absolutely complete, from cover to cover!"

"That's a find," agreed Jim. "Now go ahead and transliterate it—you're the expert on Martian pictographs."

For an hour, Barney scanned the pages of the volume. He made copious notes on sheets of paper which he inserted between the metal leaves of the book. At the end of that time, during which Jim Baler had been inspecting the searchlight-thing on the top of the little house, he called to his friend, and Jim entered the flier lugging the thing on his shoulders.

"What'cha got?" he grinned. "I brought this along. Nothing else in that shack, so we're complete except for the remnants of some very badly corroded cable that ran from this thing to a flapping end down where the tower was broken."

Barney smiled and blinked. It was strange to see this big man working studiously over a book; Barney Carroll should have been leading a horde of Venusian engineers through the Palanortis country instead of delving into the artifacts of a dead civilization.

"I think that this thing is a sort of engineer's handbook," he said. "In the front there is a section devoted to mathematical tables. You know, a table of logs to the base twelve which is because the Martians had six fingers on each hand. There is what seems to be a table of definite integrals—at least if I were writing a handbook I'd place the table of integrals at the last part of the math section. The geometry and trig is absolutely recognizable because of the designs. So is the solid geom and the analyt for the same reason. The next section seems to be devoted to chemistry; the Martians used a hexagonal figure for a benzene ring, too, and so that's established. From that we find the key to the Periodic Chart of the Atoms which is run vertically instead of horizontally, but still unique. These guys were sharp, though; they seem to have hit upon the fact that isotopes are separate elements though so close in grouping to one another that they exhibit the same properties. Finding this will uncover a lot of mystery."

"Yeah," agreed Baler, "from a book of this kind we can decipher most anything. The keying on a volume of physical constants is perfect and almost infinite in number. What do they use for Pi?"

"Circle with a double dot inside."

"And Planck's Constant?"

"Haven't hit that one yet. But we will. But to get back to the meat of this thing, the third section deals with something strange. It seems to have a bearing on this gadget from the top of the tower. I'd say that the volume was a technical volume on the construction, maintenance, and repair of the tower and its functions—whatever they are."

Barney spread the volume out for Jim to see. "That dingbat is some sort of electronic device. Or, perhaps subelectronic. Peel away that rusted side and we'll look inside."

Jim peeled a six-inch section from the side of the big metal tube, and they inspected the insides. Barney looked thoughtful for a minute and then flipped the pages of the book until he came to a diagram.

"Sure," he said exultantly, "this is she. Look, Jim, they draw a cathode like this, and the grids are made with a series of fine parallel lines. Different, but more like the real grid than our symbol of a zig-zag line. The plate is a round circle instead of a square, but that's so clearly defined that it comes out automatically. Here's your annular electrodes, and the ... call 'em deflection plates. I think we can hook this do-boodle up as soon as we get to our place in Lincoln Head."

"Let's go then. Not only would I like to see this thing work, but I'd give anything to know what it's for!"