After a brief consultation, we all three directed our steps to the summer-house which contained young Bourdon’s laboratory.  In the room itself nothing of importance was discovered; but in an enclosed recess, which we broke open, we found a curiously-fashioned glass bottle half full of iodine.

“This is it!” said Mr. ——­; “and in a powdered state too—­just ready for mixing with brandy or any other available dissolvent.”  The powder had somewhat the appearance of fine black lead.  Nothing further of any consequence being observed, we returned to the house, where the magistrate had already arrived.

Alfred Bourdon was first brought in; and he having been duly cautioned that he was not obliged to answer any question, and that what he did say would be taken down, and, if necessary, used against him, I proposed the following questions:—­

“Have you the key of your laboratory?”

“No; the door is always open.”

“Well, then, of any door or cupboard in the room?”

At this question his face flushed purple:  he stammered, “There is no”—­and abruptly paused.

“Do I understand you to say there is no cupboard or place of concealment in the room?”

“No:  here is the key.”

“Has any one had access to the cupboard or recess of which this is the key, except yourself?”

The young man shook as if smitten with ague:  his lips chattered, but no articulate sound escaped them.

“You need not answer the question,” said the magistrate, “unless you choose to do so.  I again warn you that all you say will, if necessary, be used against you.”

“No one,” he at length gasped, mastering his hesitation by a strong exertion of the will—­“no one can have had access to the place but myself.  I have never parted with the key.”

Mrs. Bourdon was now called in.  After interchanging a glance of intense agony, and, as it seemed to me, of affectionate intelligence with her son, she calmly answered the questions put to her.  They were unimportant, except the last, and that acted upon her like a galvanic shock.  It was this—­“Did you ever struggle with your son on the landing leading to the bedroom of the deceased for the possession of this bottle?” and I held up that which we had found in the recess.

A slight scream escaped her lips; and then she stood rigid, erect, motionless, glaring alternately at me and at the fatal bottle with eyes that seemed starting from their sockets.  I glanced towards the son; he was also affected in a terrible manner.  His knees smote each other, and a clammy perspiration burst forth and settled upon his pallid forehead.

“Again I caution you,” iterated the magistrate, “that you are not bound to answer any of these questions.”

The woman’s lips moved.  “No—­never!” she almost inaudibly gasped, and fell senseless on the floor.