shutter back revealing the constellation of Cygnus sprawling across the meridian. Breathing heavily, he turned the dome until Jupiter came into the center of the opening, a gleaming yellow stoplight among the faint stars of Aquarius. Then swinging the telescope around on the pier as if it were an antiaircraft gun, he sighted along the tube until the planet came darting into the field of view.
"How's the seeing?" asked Arnold, a formless black shape by the desk. He twisted the shade over the lamp until the light illuminated the chronometer and pad of paper at his elbow but left the end of the telescope in shadow.
Stoddard gave the focusing screw another touch. "Not so good," he muttered. Removing the eyepiece from the end of the telescope he substituted a longer one in its place from the box beside him. "There— that's better."
"How do the satellites look?"
"Well, just about the way the Ephemeris predicted. Callisto and Ganymede are over on the west. Europa's about a diameter of Jupiter to the east. Io doesn't seem to be anywhere around."
He lowered the seat on the observing platform a couple of notches thus enabling him to look into the telescope with less strain on his vertebrae. "Wait a minute— caught a glimpse of her at the limb just then." Arnold shot a glance at the chronometer. "Gosh, don't tell me it's going into occultation already!"
"Well, it sure looks like it."
"But it can't be that much ahead of time."
"Why not? That's what you were hoping for, wasn't it? Keep an eye on the chronometer, anyhow. I'll give you the time as close as I can in this bum seeing."
For several minutes the dome was silent except for the steady ticking of the chronometer and the low hum of traffic from Los Feliz Boulevard far below. Stoddard concentrated his every faculty on the tiny point of light projecting from the planet's disk. Sometimes he felt sure it must be gone only to have it flash into view again. He waited until it had remained out of sight for an unusually long interval. "All right, get ready," he warned. "Now!"
"Seven-thirty-three-zero-zero," said Arnold, writing down the numbers at the top of the record sheet. Stoddard rose painfully from his cramped position at the end of the telescope and began cautiously exercising one leg. His partner continued figuring busily for another five minutes. Presently he leaned back and began tapping the desk thoughtfully with the tip of his pencil.
"What's the answer?" said Stoddard, limping across the room.
"Well, according to these figures," Arnold replied, speaking with elaborate. casualness, "the occultation occurred just thirty-five minutes and ten seconds ahead of time."
For a moment neither spoke. Then Stoddard let out a belly laugh that shattered the peaceful calm that had hitherto enveloped Observatory Hill.
