Taking an arm of each, Sandy led them, wordless, up the path.

Spying carefully to be sure that Mr. Whiteside was not in sight, and being certain that no one else was watching, Sandy led his chums into the hangar.

Across to one of its longer sides he led them.

“These are the switches that work the rolling door motor, you remember?”

“Yes, Sandy. What?——”

“Look at them before it gets too dark, Dick. Do you see anything strange? You know as much about wiring circuits as I do. We both built amateur short-wave sending and receiving sets. You, too, Larry. What isn’t right about the switches or—the wires?”

Thus guided, both studied the switches.

All Larry saw was that the wires were of a braided form.

“But—are they?” He pulled a wire out a trifle from the sheath.

Then his comrades observed what had first attracted Sandy’s attention, puzzled him and led to further search.