As he left the screening room, Roger met Potts.

“Tip,” he hailed, “Did you get anything on the ‘sound’ film in the one-snap-a-minute camera?”

“The one that took pictures of them mouses?”

“The one by the rats’ cage—yes.”

“You know about sound, Rog’. It ain’t just a lot of single pictures.” Potts wanted to air his knowledge. “Sound is a maintained concession of peaks an’ valleys on the sound track.”

“You always will use a .44 caliber word when a BB. size would hit what you aim at and not blow your idea to bits, Tip. You mean that sound is a ‘sustained succession’—I know that. And single frames, if they showed any sound impression at all, would give little pops.”

“So I didn’t bother.”

“But, Tip! There was a lot of wild zig-zag marking on the tape in the seismograph-like recorder; and it seemed as though the ‘continuous’ taking lever had been shifted before he—it—whatever was there, stopped the whole business by breaking off the wiring.”

“We can try.”

When they had developed the negative, made a print and fixed and washed it, Roger threaded the fifteen frames of continuous shots in place and projected with the speakers cut in.