“Four hours each. But sometimes they’re on for eight hours.”
“What do you mean?”
“Well, there are two on duty daytimes—”
“Never mind that either—I’m not interested in their complete schedule. How many operators are in the wireless room now?”
“Only one. He’s doing his trick from eight till midnight.”
“Good. Now we’re getting somewhere. How about from midnight on?”
“Another guy comes on duty then.”
“For how long?”
“Till eight in the morning.”
“He’s alone all that time? Are you sure?”