Kennedy smiled. "Every one seems to be—even Whitney," he returned, twisting a set-screw until he had the alignment of the various parts as he wanted it.

The telephone bell rang.

"Do you want to answer it?" I asked Craig.

"No," he replied, not even looking up from his work. "Find out who it is. Unless it is something very important say I am out on an investigation and that you have heard from me; that I shall not be either at the laboratory or the apartment until tomorrow morning. I must get this done to-night."

I took down the receiver.

"Hello, is this Professor Kennedy?" I recognized a voice.

"No," I replied. "Is there any message I can take?"

"This is Mr. Lockwood," came back the information I had already guessed. "When do you expect him?"

"It's Lockwood," I whispered to Craig, my hand over the transmitter.

"See what he wants," returned Craig. "Tell him what I told you."