“You remember Yorke-Bannerman’s case,” he went on.  “He committed a murder—­”

“Let me take the basin!” I cried, for I saw Hilda’s hands giving way a second time, and I was anxious to spare her.

“No, thank you,” she answered low, but in a voice that was full of suppressed defiance.  “I will wait and hear this out.  I prefer to stop here.”

As for Sebastian, he seemed now not to notice her, though I was aware all the time of a sidelong glance of his eye, parrot-wise, in her direction.  “He committed a murder,” he went on, “by means of aconitine—­then an almost unknown poison; and, after committing it, his heart being already weak, he was taken himself with symptoms of aneurism in a curious form, essentially similar to these; so that he died before the trial—­a lucky escape for him.”

He paused rhetorically once more; then he added in the same tone:  “Mental agitation and the terror of detection no doubt accelerated the fatal result in that instance.  He died at once from the shock of the arrest.  It was a natural conclusion.  Here we may hope for a more successful issue.”

He spoke to the students, of course, but I could see for all that that he was keeping his falcon eye fixed hard on Hilda’s face.  I glanced aside at her.  She never flinched for a second.  Neither said anything directly to the other; still, by their eyes and mouths, I knew some strange passage of arms had taken place between them.  Sebastian’s tone was one of provocation, of defiance, I might almost say of challenge.  Hilda’s air I took rather for the air of calm and resolute, but assured, resistance.  He expected her to answer; she said nothing.  Instead of that, she went on holding the basin now with fingers that would not tremble.  Every muscle was strained.  Every tendon was strung.  I could see she held herself in with a will of iron.

The rest of the episode passed off quietly.  Sebastian, having delivered his bolt, began to think less of Hilda and more of the patient.  He went on with his demonstration.  As for Hilda, she gradually relaxed her muscles, and, with a deep-drawn breath, resumed her natural attitude.  The tension was over.  They had had their little skirmish, whatever it might mean, and had it out; now, they called a truce over the patient’s body.

When the case had been disposed of, and the students dismissed, I went straight into the laboratory to get a few surgical instruments I had chanced to leave there.  For a minute or two, I mislaid my clinical thermometer, and began hunting for it behind a wooden partition in the corner of the room by the place for washing test-tubes.  As I stooped down, turning over the various objects about the tap in my search, Sebastian’s voice came to me.  He had paused outside the door, and was speaking in his calm, clear tone, very low, to Hilda.  “So now we understand one another, Nurse Wade,” he said, with a significant sneer.  “I know whom I have to deal with!”