On that same evening, Thursday, July 22d, two astronomers attached to the Naval Observatory sat in the half darkness of the meridian-circle room watching the firmament sweep slowly across the aperture of the giant lens. The chamber was as quiet as the grave, the two men rarely speaking as they noted their observations. Paris might be taken, Berlin be razed, London put to the torch; a million human beings might be blown into eternity, or the shrieks of mangled creatures lying in heaps before pellet-strewn barbed-wire entanglements rend the summer night; great battleships of the line might plunge to the bottom, carrying their crews with them; and the dead of two continents rot unburied—yet unmoved the stars would pursue their nightly march across the heavens, cruel day would follow pitiless night, and the careless earth follow its accustomed orbit as though the race were not writhing in its death agony. Gazing into the infinity of space human existence seemed but the scum upon a rainpool, human warfare but the frenzy of insectivora. Unmindful of the starving hordes of Paris and Berlin, of plague-swept Russia, or of the drowned thousands of the North Baltic Fleet, these two men calmly studied the procession of the stars—the onward bore of the universe through space, and the spectra of newborn or dying worlds.

It was a suffocatingly hot night and their foreheads reeked with sweat. Dim shapes on the walls of the room indicated what by day was a tangle of clockwork and recording instruments, connected by electricity with various buttons and switches upon the table. The brother of the big clock in the wireless operating room hung nearby, its face illuminated by a tiny electric lamp, showing the hour to be eleven-fifty. Occasionally the younger man made a remark in a low tone, and the elder wrote something on a card.

"The 'seeing' is poor to-night," said Evarts, the younger man. "The upper air is full of striae and, though it seems like a clear night, everything looks dim—a volcanic haze probably. Perhaps the Aleutian Islands are in eruption again."

"Very likely," answered Thornton, the elder astronomer. "The shocks this afternoon would indicate something of the sort."

"Curious performance of the magnetic needle. They say it held due east for several minutes," continued Evarts, hoping to engage his senior in conversation—almost an impossibility, as he well knew.

Thornton did not reply. He was carefully observing the infinitesimal approach of a certain star to the meridian line, marked by a thread across the circle's aperture. When that point of light should cross the thread it would be midnight, and July 22, 1916, would be gone forever. Every midnight the indicating stars crossed the thread exactly on time, each night a trifle earlier than the night before by a definite and calculable amount, due to the march of the earth around the sun. So they had crossed the lines in every observatory since clocks and telescopes had been invented. Heretofore, no matter what cataclysm of nature had occurred, the star had always crossed the line not a second too soon or a second too late, but exactly on time. It was the one positively predictable thing, foretellable for ten or for ten thousand years by a simple mathematical calculation. It was surer than death or the tax-man. It was absolute.

Thornton was a reserved man of few words—impersonal, methodical, serious. He spent many nights there with Evarts, hardly exchanging a phrase with him, and then only on some matter immediately concerned with their work. Evarts could dimly see his long, grave profile bending over his eyepiece, shrouded in the heavy shadows across the table. He felt a great respect, even tenderness, for this taciturn, high-principled, devoted scientist. He had never seen him excited, hardly ever aroused. He was a man of figures, whose only passion seemed to be the "music of the spheres."

A long silence followed, during which Thornton seemed to bend more intently than ever over his eyepiece. The hand of the big clock slipped gradually to midnight.

"There's something wrong with the clock," said Thornton suddenly, and his voice sounded curiously dry, almost unnatural. "Telephone to the equatorial room for the time."

Puzzled by Thornton's manner Evarts did as instructed.

"Forty seconds past midnight," came the reply from the equatorial observer.

Evarts repeated the answer for Thornton's benefit, looking at their own clock at the same time. It pointed to exactly forty seconds past the hour. He heard Thornton suppress something like an oath.

"There's something the matter!" repeated Thornton dumbly. "Aeta isn't within five minutes of crossing. Both clocks can't be wrong!"

He pressed a button that connected with the wireless room.

"What's the time?" he called sharply through the nickel-plated speaking-tube.

"Forty-five seconds past the hour," came the answer. Then: "But I want to see you, sir. There's something queer going on. May I come in?"

"Come!" almost shouted Thornton.

A moment later the flushed face of Williams, the night operator, appeared in the doorway.

"Excuse me, sir," he stammered, "but something fierce must have happened! I thought you ought to know. The Eiffel Tower has been trying to talk to us for over two hours, but I can't get what he's saying."

"What's the matter—atmospherics?" snapped Evarts.

"No; the air was full of them, sir—shrieking with them you might say; but they've stopped now. The trouble has been that I've been jammed by the Brussels station talking to the Belgian Congo—same wave length—and I couldn't tune Brussels out. Every once in a while I'd get a word of what Paris was saying, and it's always the same word—'heure.' But just now Brussels stopped sending and I got the complete message of the Eiffel Tower. They wanted to know our time by Greenwich. I gave it to 'em. Then Paris said to tell you to take your transit with great care and send result to them immediately——"

The ordinarily calm Thornton gave a great suspiration and his face was livid. "Aeta's just crossed—we're five minutes out! Evarts, am I crazy? Am I talking straight?"

Evarts laid his hand on the other's arm.

"The earthquake's knocked out your transit," he suggested.

"And Paris—how about Paris?" asked Thornton. He wrote something down on a card mechanically and started for the door. "Get me the Eiffel Tower!" he ordered Williams.

The three men stood motionless, as the wireless man sent the Eiffel Tower call hurtling across the Atlantic:

"ETA—ETA—ETA."

"All right," whispered Williams, "I've got 'em."

"Tell Paris that our clocks are all out five minutes according to the meridian."

Williams worked the key rapidly, and then listened.

"The Eiffel Tower says that their chronometers also appear to be out by the same time, and that Greenwich and Moscow both report the same thing. Wait a minute! He says Moscow has wired that at eight o'clock last evening a tremendous aurora of bright yellow light was seen to the northwest, and that their spectroscopes showed the helium line only. He wants to know if we have any explanation to offer——"

"Explanation!" gasped Evarts. "Tell Paris that we had earthquake shocks here together with violent seismic movements, sudden rise in barometer, followed by fall, statics, and erratic variation in the magnetic needle."

"What does it all mean?" murmured Thornton, staring blankly at the younger man.

The key rattled and the rotary spark whined into a shriek. Then silence.

"Paris says that the same manifestations have been observed in Russia, Algeria, Italy, and London," called out Williams. "Ah! What's that? Nauen's calling." Again he sent the blue flame crackling between the coils. "Nauen reports an error of five minutes in their meridian observations according to the official clocks. And hello! He says Berlin has capitulated and that the Russians began marching through at daylight—that is about two hours ago. He says he is about to turn the station over to the Allied Commissioners, who will at once assume charge."

Evarts whistled.

"How about it?" he asked of Thornton.

The latter shook his head gravely.

"It may be—explainable—or," he added hoarsely, "it may mean the end of the world."

Williams sprang from his chair and confronted Thornton.

"What do you mean?" he almost shouted.

"Perhaps the universe is running down!" said Evarts soothingly. "At any rate, keep it to yourself, old chap. If the jig is up there's no use scaring people to death a month or so too soon!"

Thornton grasped an arm of each.

"Not a word of this to anybody!" he ground out through compressed lips. "Absolute silence, or hell may break loose on earth!"