photograph the wound."

"Put yourself in the position of the body," said Malcolm Sage.

The inspector walked to the centre of the room, near a
highly-polished table, dropped on to the floor and, after a moment's
pause, turned and lay on his left side, with right arm outstretched.

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.

"No one," was the reply.

Malcolm Sage rose to his feet. For some minutes he stood looking
down at the fireplace, stroking the back of his head, deep in
thought.

Presently he picked up the poker, a massive steel affair, and
proceeded to examine the fire-end with great minuteness.

"It was done with the other end," said the inspector. "He must have
wiped it afterwards. There was no sign of blood or hair."

Malcolm Sage ignored the remark, and continued to regard the
business-end of the poker. Walking over to the door, he examined the
fastenings. Having taken a general survey, he next proceeded to a
detailed scrutiny of everything the place contained. From the
fireplace he picked up what looked like a cinder and placed it in a
small box, which he put in his pocket.

The po