Q. What did you use?
Again the witness hesitated while everyone, save only Maitland and Godin, leaned eagerly forward to catch his reply. At length it came in a voice scarcely above a whisper.
A. Anhydrous hydrocyanic acid.
A long-drawn “Hum!” escaped from Maitland, while M. Godin gave not the slightest indication of surprise. It was quite evident to us all that the astute Frenchman had acquired complete control of the case before he had arrested the assassin. At this juncture the Court said, addressing Maitland:
“This substance is extremely poisonous, I take it.”
“Your Honour,” Maitland replied, “it is the most fatal of all poisons known to chemists. It is also called cyanhydric, and, more commonly, prussic acid. An insignificant amount, when inhaled or brought into contact with the skin, causes immediate death. If a drop be placed upon the end of a glass rod and brought toward the nose of a live rabbit he will be dead before it reaches him.”
A profound silence—the death-like quiet which accompanies an almost breaking tension—reigned in the court-room as Maitland turned again to Latour.
Q. I understand you to say you used anhydrous hydrocyanic or cyanhydric acid.
A. Yes, sir.
Q. Do you sufficiently understand chemistry to use these terms with accuracy? Might you not have used potassium cyanide or prussiate of potash?