Or is Sperry right, and do certain individuals manifest powers of a purely physical nature, but powers which Sperry characterizes as the survival of some long-lost development by which at one time we knew how to liberate a forgotten form of energy?

Who can say?  We do not know.  We have had to accept these things as they have been accepted through the ages, and give them either a spiritual or a purely natural explanation, as our minds happen to be adventurous or analytic in type.

But outside of the purely physical phenomena of those seances, we are provided with an explanation which satisfies the Neighborhood Club, even if it fails to satisfy the convinced spiritist.  We have been accused merely of substituting one mystery for another, but I reply by saying that the mystery we substitute is not a mystery, but an acknowledged fact.

On Tuesday morning I wakened after an uneasy night.  I knew certain things, knew them definitely in the clear light of morning.  Hawkins had the letters that Arthur Wells had found; that was one thing.  I had not taken Ellingham’s stick to Mrs. Dane’s house; that was another.  I had not done it.  I had placed it on the table and had not touched it again.

But those were immaterial, compared with one outstanding fact.  Any supernatural solution would imply full knowledge by whatever power had controlled the medium.  And there was not full knowledge.  There was, on the contrary, a definite place beyond which the medium could not go.

She did not know who had killed Arthur Wells.

To my surprise, Sperry and Herbert Robinson came together to see me that morning at my office.  Sperry, like myself, was pale and tired, but Herbert was restless and talkative, for all the world like a terrier on the scent of a rat.

They had brought a newspaper account of an attempt by burglars to rob the Wells house, and the usual police formula that arrests were expected to be made that day.  There was a diagram of the house, and a picture of the kitchen door, with an arrow indicating the bullet-hole.

“Hawkins will be here soon,” Sperry said, rather casually, after I had read the clipping.

“Here?”

“Yes.  He is bringing a letter from Miss Jeremy.  The letter is merely a blind.  We want to see him.”

Herbert was examining the door of my office.  He set the spring lock.  “He may try to bolt,” he explained.  “We’re in this pretty deep, you know.”

“How about a record of what he says?” Sperry asked.

I pressed a button, and Miss Joyce came in.  “Take the testimony of the man who is coming in, Miss Joyce,” I directed.  “Take everything we say, any of us.  Can you tell the different voices?”

She thought she could, and took up her position in the next room, with the door partly open.

I can still see Hawkins as Sperry let him in—­a tall, cadaverous man of good manners and an English accent, a superior servant.  He was cool but rather resentful.  I judged that he considered carrying letters as in no way a part of his work, and that he was careful of his dignity.  “Miss Jeremy sent this, sir,” he said.