"Step out here a moment, and I will show you."
Nick took the senator into the hallway, and pointed toward the balustrade that ascended beside the stairs.
"Don't you notice," he said, "that there is a strip of metal, lying along the top of the rail?"
"Yes."
"Look closer, and you will see that there is also a strip of insulation beneath it, to protect the woodwork."
"I see it."
"Well, every place in the house where a stranger, upon entering, would be likely to rest his hand, is wired and insulated in just that manner-for those strips of metal are what you might call flat wires; no?"
"Yes."
"Very good. Now you must understand that the other house-the one back of this one-is protected in the same manner."
"But-"