I went out from him, much perturbed.  The Sebastian I had once admired and worshipped was beginning to pass from me; in his place I found a very complex and inferior creation.  My idol had feet of clay.  I was loth to acknowledge it.

I stalked along the corridor moodily towards my own room.  As I passed Hilda Wade’s door, I saw it half ajar.  She stood a little within, and beckoned me to enter.

I passed in and closed the door behind me.  Hilda looked at me with trustful eyes.  Resolute still, her face was yet that of a hunted creature.  “Thank Heaven, I have one friend here, at least!” she said, slowly seating herself.  “You saw me catch and conceal the needle?”

“Yes, I saw you.”

She drew it forth from her purse, carefully but loosely wrapped up in a small tag of tissue-paper.  “Here it is!” she said, displaying it.  “Now, I want you to test it.”

“In a culture?” I asked; for I guessed her meaning.

She nodded.  “Yes, to see what that man has done to it.”

“What do you suspect?”

She shrugged her graceful shoulders half imperceptibly.

“How should I know?  Anything!”

I gazed at the needle closely.  “What made you distrust it?” I inquired at last, still eyeing it.

She opened a drawer, and took out several others.  “See here,” she said, handing me one; “These are the needles I keep in antiseptic wool—­the needles with which I always supply the Professor.  You observe their shape—­the common surgical patterns.  Now, look at this needle, with which the Professor was just going to prick my finger!  You can see for yourself at once it is of bluer steel and of a different manufacture.”

“That is quite true,” I answered, examining it with my pocket lens, which I always carry.  “I see the difference.  But how did you detect it?”

“From his face, partly; but partly, too, from the needle itself.  I had my suspicions, and I was watching him closely.  Just as he raised the thing in his hand, half concealing it, so, and showing only the point, I caught the blue gleam of the steel as the light glanced off it.  It was not the kind I knew.  Then I withdrew my hand at once, feeling sure he meant mischief.”

“That was wonderfully quick of you!”

“Quick?  Well, yes.  Thank Heaven, my mind works fast; my perceptions are rapid.  Otherwise—­” she looked grave.  “One second more, and it would have been too late.  The man might have killed me.”

“You think it is poisoned, then?”

Hilda shook her head with confident dissent.  “Poisoned?  Oh, no.  He is wiser now.  Fifteen years ago, he used poison.  But science has made gigantic strides since then.  He would not needlessly expose himself to-day to the risks of the poisoner.”

“Fifteen years ago he used poison?”

She nodded, with the air of one who knows.  “I am not speaking at random,” she answered.  “I say what I know.  Some day I will explain.  For the present, it is enough to tell you I know it.”