The grave profile of the astronomer showed through the dim light from the shrouded electric lamp like the head of an ancient statue of some Greek philosopher. Before him lay a litter of white papers covered with figures and an open book of logarithms. Immured in the interior of the great dome, with its monumental walls like those of an ancient Egyptian pyramid, they could hear no sound save the slow tick of the sidereal clock and the faint whir of the complicated machinery that drove the telescope in its infallible following of the movements of the solar system. For upward of two minutes, Thornton remained unconscious of Hooker's presence. Then, with a sigh, he laid down his pencil and, looking up, observed his friend for the first time.
"Hello, Bennie," he exclaimed, with a suggestion of excitement in his ordinarily calm voice; "pull your chair up here! We've got something big—the biggest thing, in fact, that has ever happened in astronomy! We got the elements of Battelli's comet yesterday. Unless I've made some mistake in my figures, there's going to be a smash-up in the universe!"
From Thornton, the conservative, such a declaration had immeasurable significance.
"You mean it's going to hit the earth?" asked Hooker, with interest.
"No," answered Thornton; "but it looks as if it would strike one of the smaller asteroids in a head-on collision—and if it does—"
"Something will drop," finished Hooker. "Which asteroid?"
"Medusa—one I've been following in its orbit for more than two years—a small planet, largely composed of pitchblende."
Hooker pursed his lips into a whistle.
"What do you really suppose will happen?" he inquired.
"No one can tell," replied, the astronomer. "The collision might check Medusa in its orbit and cause it to fall into the sun. In falling, it might cross the earth's path and strike us—it might mean the end of the world!"