“Merely that I wish to obtain my impressions uncoloured.  This delicate clue I am working on might be so easily blurred by the thought-currents of another mind with strongly preconceived ideas.”

“Perfectly.  I understand,” rejoined the soldier, though with an expression of countenance that plainly contradicted his words.  “Then I will wait here with the dogs; and we’ll have a look at the laundry on our way home.”

I turned once to look back as we clambered over the low stone wall built by the late owner, and saw his straight, soldierly figure standing in the sunlit field watching us with a curiously intent look on his face.  There was something to me incongruous, yet distinctly pathetic, in the man’s efforts to meet all far-fetched explanations of the mystery with contempt, and at the same time in his stolid, unswerving investigation of it all.  He nodded at me and made a gesture of farewell with his hand.  That picture of him, standing in the sunshine with his big dogs, steadily watching us, remains with me to this day.

Dr. Silence led the way in among the twisted trunks, planted closely together in serried ranks, and I followed sharp at his heels.  The moment we were out of sight he turned and put down his gun against the roots of a big tree, and I did likewise.

“We shall hardly want these cumbersome weapons of murder,” he observed, with a passing smile.

“You are sure of your clue, then?” I asked at once, bursting with curiosity, yet fearing to betray it lest he should think me unworthy.  His own methods were so absolutely simple and untheatrical.

“I am sure of my clue,” he answered gravely.  “And I think we have come just in time.  You shall know in due course.  For the present—­be content to follow and observe.  And think, steadily.  The support of your mind will help me.”

His voice had that quiet mastery in it which leads men to face death with a sort of happiness and pride.  I would have followed him anywhere at that moment.  At the same time his words conveyed a sense of dread seriousness.  I caught the thrill of his confidence; but also, in this broad light of day, I felt the measure of alarm that lay behind.

“You still have no strong impressions?” he asked.  “Nothing happened in the night, for instance?  No vivid dreamings?”

He looked closely for my answer, I was aware.

“I slept almost an unbroken sleep.  I was tremendously tired, you know, and, but for the oppressive heat—­”

“Good!  You still notice the heat, then,” he said to himself, rather than expecting an answer.  “And the lightning?” he added, “that lightning out of a clear sky—­that flashing—­did you notice that?”

I answered truly that I thought I had seen a flash during a moment of wakefulness, and he then drew my attention to certain facts before moving on.

“You remember the sensation of warmth when you put the letter to your forehead in the train; the heat generally in the house last evening, and, as you now mention, in the night.  You heard, too, the Colonel’s stories about the appearances of fire in this wood and in the house itself, and the way his brother and the gamekeeper came to their deaths twenty years ago.”