“I was thinking aloud.”
“But you spoke of an electric drill.”
“Yes.”
Nick Carter, for once, had been caught napping. He had spoken when he should have remained silent.
“That makes me think,” continued the man, “that the two doctors downstairs are cranks on electricity.”
“What do they do with electricity?”
“They have a motor down there, and they have been drilling all sorts of substances.”
“How long has this been going on?”
“Ever since they have lived there.”
Nick thought of the armature he had found in the rooms below not long before, and remained silent.