From just inside the door Malcolm Sage looked about him. At the left extremity a second door gave access to another apartment, which the professor used as a bedroom.
A little to the right of the door, on the opposite side, stood the fireplace. This was full of ashes, apparently the charred remains of a quantity of paper that had been burnt. On the hearth were several partially-charred envelopes, and the paper-basket contained a number of torn-up letters.
"That will do, Carfon," said Malcolm Sage, as he walked over to the fireplace and, dropping on one knee, carefully examined the ashes, touching them here and there with the poker.
He picked up something that glittered and held it out to the inspector who scrambled to his feet, and stood looking down with keen professional interest.
"Piece of a test tube," remarked Malcolm Sage, as he placed the small piece of glass upon the table.
"Moses' aunt!" gasped the inspector. "I missed that, though I saw a lot of bits of glass. I thought it was an electric bulb."
"Somebody had ground it to powder with his heel, all except this piece. Looks as if there might have been more than one," he added more to himself than to the inspector.
"These are not letters," he continued without looking up.
"Not letters?"
"The paper is all of the same quality. By the way, has anyone disturbed it?" He indicated the grate.