Roger rubbed his eyes, snapped awake.
“Is it all right at the lab.?”
“I knew it would be. We left Tip to take turns watching with the men from the Falcon Patrol Agency. Two at a time, one on each floor. But I never count on human watchmen alone. They can be careless,” Grover talked as Roger dressed.
“I know. Capacity-overloading plates all around, so that anybody or anything that got near any apparatus would overload an aerial field and upset a delicate tube and open a relay, stamping the time, and starting cameras with sound-films in them.”
“Exactly. Just talked to Potts. Nothing at all happened.”
Arriving at the laboratory, earlier than the staff, Roger and the Chief verified the static condition.
“What do you think of this?” Grover took his cousin to the sound-recording mechanism, the type that uses a large phonograph record for the sound that synchronizes with a film in certain motion picture studios.
He explained that as a double-check on any possible development, he had hooked up the recorder to a separate microphone system, all concealed flat-disk, super-sensitive diaphragm models, that were set in operation by any interruption of infra-red beams.
“That’s something!” commended Roger, examining the arrangements, “of course, with the reports in, I may as well put away the record to keep dust off it during the day.”
Grover agreed.